Tertiary Birds

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The Paleogene fossil record of birds in Europe Gerald Mayr Forschungsinstitut Senckenberg, Sektion Ornithologie, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany. (Email : [email protected]) (Received 26 July 2004 ; revised 22 February 2005 ; accepted 23 February 2005 ) ABSTRACT The Paleogene (Paleocene–Oligocene) fossil record of birds in Europe is reviewed and recent and fossil taxa are placed into a phylogenetic framework, based on published cladistic analyses. The pre-Oligocene European avifauna is characterized by the complete absence of passeriform birds, which today are the most diverse and abundant avian taxon. Representatives of small non-passeriform perching birds thus probably had similar ecological niches before the Oligocene to those filled by modern passerines. The occurrence of passerines towards the Lower Oligocene appears to have had a major impact on these birds, and the surviving crown-group members of many small arboreal Eocene taxa show highly specialized feeding strategies not found or rare in passeriform birds. It is detailed that no crown-group members of modern ‘families’ are known from pre- Oligocene deposits of Europe, or anywhere else. The phylogenetic position of Paleogene birds thus indicates that diversification of the crown-groups of modern avian ‘ families ’ did not take place before the Oligocene, irrespective of their relative position within Neornithes (crown-group birds). The Paleogene fossil record of birds does not even support crown-group diversification of Galliformes, one of the most basal taxa of neognathous birds, before the Oligocene, and recent molecular studies that dated diversification of galliform crown-group taxa into the Middle Cretaceous are shown to be based on an incorrect interpretation of the fossil taxa used for molecular clock calibrations. Several taxa that occur in the Paleogene of Europe have a very different distribution than their closest extant relatives. The modern survivors of these Paleogene lineages are not evenly distributed over the continents, and especially the great number of taxa that are today restricted to South and Central America is noteworthy. The occurrence of stem-lineage representatives of many taxa that today have a restricted Southern Hemisphere distribution conflicts with recent hypotheses on a Cretaceous vicariant origin of these taxa, which were deduced from the geographical distribution of the basal crown-group members. Key words : Aves, Paleogene, Europe, fossil record, biogeography, diversification of neornithine taxa. CONTENTS I. Introduction ................................................................................................................................................. 516 II. Composition of the Paleogene European avifauna ................................................................................ 516 (1) Palaeognathae ........................................................................................................................................ 516 (2) Neognathae ............................................................................................................................................ 517 (a) Galliformes (landfowl) ..................................................................................................................... 517 (b) Anseriformes (waterfowl, incl. Gastornithidae) ........................................................................... 519 (c) Gaviiformes (loons) and Procellariiformes (tubenoses and petrels) ........................................... 521 (d) Pelagornithidae (bony-toothed birds) ............................................................................................ 521 (e) ‘Pelecaniformes’ (pelicans, cormorants, and allies) .................................................................... 521 ( f ) Charadriiformes (shorebirds, incl. Turnicidae) ........................................................................... 522 ( g) Columbidae (doves and pigeons) and Pteroclidae (sandgrouse) ................................................ 522 (h) Threskiornithidae (ibises), Ardeidae (herons), and Ciconiidae (storks) ..................................... 522 (i) Phoenicopteriformes (flamingos) .................................................................................................... 523 ( j ) ‘Gruiformes’ (cranes, rails, and allies) .......................................................................................... 523 (k) ‘Falconiformes’ (diurnal birds of prey) ......................................................................................... 524 (l ) Strigiformes (owls) ............................................................................................................................ 524 Biol. Rev. (2005), 80, pp. 515–542. f 2005 Cambridge Philosophical Society 515 doi:10.1017/S1464793105006779 Printed in the United Kingdom

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Tertiary Birds

Transcript of Tertiary Birds

  • The Paleogene fossil record of birds in Europe

    Gerald Mayr

    Forschungsinstitut Senckenberg, Sektion Ornithologie, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany.

    (Email : [email protected])

    (Received 26 July 2004; revised 22 February 2005; accepted 23 February 2005)

    ABSTRACT

    The Paleogene (PaleoceneOligocene) fossil record of birds in Europe is reviewed and recent and fossil taxaare placed into a phylogenetic framework, based on published cladistic analyses. The pre-Oligocene Europeanavifauna is characterized by the complete absence of passeriform birds, which today are the most diverse andabundant avian taxon. Representatives of small non-passeriform perching birds thus probably had similarecological niches before the Oligocene to those lled by modern passerines. The occurrence of passerines towardsthe Lower Oligocene appears to have had a major impact on these birds, and the surviving crown-groupmembers of many small arboreal Eocene taxa show highly specialized feeding strategies not found or rare inpasseriform birds. It is detailed that no crown-group members of modern families are known from pre-Oligocene deposits of Europe, or anywhere else. The phylogenetic position of Paleogene birds thus indicates thatdiversication of the crown-groups of modern avian families did not take place before the Oligocene, irrespectiveof their relative position within Neornithes (crown-group birds). The Paleogene fossil record of birds does noteven support crown-group diversication of Galliformes, one of the most basal taxa of neognathous birds, beforethe Oligocene, and recent molecular studies that dated diversication of galliform crown-group taxa into theMiddle Cretaceous are shown to be based on an incorrect interpretation of the fossil taxa used for molecular clockcalibrations. Several taxa that occur in the Paleogene of Europe have a very dierent distribution than theirclosest extant relatives. The modern survivors of these Paleogene lineages are not evenly distributed over thecontinents, and especially the great number of taxa that are today restricted to South and Central America isnoteworthy. The occurrence of stem-lineage representatives of many taxa that today have a restricted SouthernHemisphere distribution conicts with recent hypotheses on a Cretaceous vicariant origin of these taxa, whichwere deduced from the geographical distribution of the basal crown-group members.

    Key words : Aves, Paleogene, Europe, fossil record, biogeography, diversication of neornithine taxa.

    CONTENTS

    I. Introduction ................................................................................................................................................. 516II. Composition of the Paleogene European avifauna ................................................................................ 516

    (1) Palaeognathae ........................................................................................................................................ 516(2) Neognathae ............................................................................................................................................ 517

    (a) Galliformes (landfowl) ..................................................................................................................... 517(b) Anseriformes (waterfowl, incl. Gastornithidae) ........................................................................... 519(c) Gaviiformes (loons) and Procellariiformes (tubenoses and petrels) ........................................... 521(d) Pelagornithidae (bony-toothed birds) ............................................................................................ 521(e) Pelecaniformes (pelicans, cormorants, and allies) .................................................................... 521( f ) Charadriiformes (shorebirds, incl. Turnicidae) ........................................................................... 522(g) Columbidae (doves and pigeons) and Pteroclidae (sandgrouse) ................................................ 522(h) Threskiornithidae (ibises), Ardeidae (herons), and Ciconiidae (storks) ..................................... 522(i) Phoenicopteriformes (amingos) .................................................................................................... 523( j ) Gruiformes (cranes, rails, and allies) .......................................................................................... 523(k) Falconiformes (diurnal birds of prey) ......................................................................................... 524(l ) Strigiformes (owls) ............................................................................................................................ 524

    Biol. Rev. (2005), 80, pp. 515542. f 2005 Cambridge Philosophical Society 515doi:10.1017/S1464793105006779 Printed in the United Kingdom

  • (m)Psittaciformes (parrots) .................................................................................................................... 525(n) Coliiformes (mousebirds) ................................................................................................................ 526(o) Musophagidae (turacos) and Cuculidae (cuckoos) ...................................................................... 527(p) Leptosomidae (cuckoo-rollers) and Podargidae (frogmouths) .................................................... 527(q) Cypselomorphae (aerial insectivores and hummingbirds) .......................................................... 527(r) Trogoniformes (trogons) .................................................................................................................. 529(s) Coraciiformes, Upupiformes, Alcediniformes (rollers, hoopoes, kingshers and allies) ......... 529(t) Piciformes (jacamars, pubirds, woodpeckers, and allies) .......................................................... 530(u) Primoscenidae (primoscenids) and Passeriformes (passerines or songbirds) ............................ 531

    III. Biogeographic anities of Paleogene European birds ........................................................................... 531(1) Australia ................................................................................................................................................. 531(2) Africa ...................................................................................................................................................... 531(3) South and Central America ................................................................................................................ 531

    IV. Diversication time of modern neornithine lineages .............................................................................. 533V. Conclusions .................................................................................................................................................. 534VI. Acknowledgements ...................................................................................................................................... 535VII. References .................................................................................................................................................... 535

    I. INTRODUCTION

    Europe has the most complete and best studied Paleogene,i.e. PaleoceneOligocene (6524 million years ago), fossilrecord of birds, and some sites have yielded numerouswell-preserved avian remains (Table 1). However, despiteintensive study of these and other localities in the past dec-ades, much uncertainty still exists on the exact compositionof the Paleogene European avifauna.Earlier identications of isolated, fragmentary remains

    are often very doubtful, given the mosaic character distri-bution (e.g. Olson, 1977a) in Paleogene birds. Most prob-lematic in this regard is the description of many species fromthe Eocene of England that are based on non-comparableelements of dierent parts of the skeleton (Harrison &Walker, 1976 c, 1977, 1979a, b ; see Steadman, 1981 andbelow). In addition, most earlier assignments of Paleogenebirds to modern groups were not established with derivedcharacters (e.g. Cracraft, 1980) but are based on overallsimilarity that, in the case of Paleogene taxa, can be quitemisleading. If fossil birds are assigned to modern taxa, andespecially if conclusions about the diversication time ofthese are drawn, it is further important to assess whether thefossil species are members of the crown-group (i.e. belong toa clade including the stem species of this modern taxonand all its descendants), or are stem-group representatives(i.e. are outside the crown-group). Unfortunately, such adistinction has also been made in recent years only.The Paleogene avian record from Europe is in dire need

    of revision, as many new avian taxa have been describedin the past decade, quickly outdating the existing earliersurveys (Olson, 1985; Mlkovsky`, 1996b ; Bochenski, 1997).A recently published catalogue by Mlkovsky` (2002) is avaluable source for the species described until the date ofits publication and the corresponding references. However,that study uses a very unorthodox and often evidentlyincorrect taxonomy and phylogeny (see Mourer-Chauvire,2004 for a review), and numerous taxa are synonymizedwithout rst-hand examination of the specimens.

    Here, I review the Paleogene avifauna of Europe andevaluate its paleobiogeographic relationships and impli-cations for the timing of the origin of the modern taxa. Thisstudy is not intended to be a list of all Paleogene speciesthat have been described so far, but a survey on those taxathat are known from suciently well-preserved remains toascertain their distinctiveness. Based on published cladisticanalyses, several recent and fossil taxa are placed into aphylogenetic framework and derived characters are listedthat support the proposed phylogenies. The temporal dis-tribution of the taxa is summarized in Table 2.

    II. COMPOSITION OF THE PALEOGENE

    EUROPEAN AVIFAUNA

    (1) Palaeognathae

    Virtually all recent phylogenetic analyses support mono-phyly of the Palaeognathae, i.e. a clade including Tinamidae(tinamous) and the ightless ratites (see Sibley & Ahlquist,1990; Livezey & Zusi, 2001; Mayr & Clarke, 2003). Palaeo-gnathous birds today only occur in the SouthernHemispherebut are represented with several taxa in the Paleogene ofEurope.The Lithornithidae were reported from the Fur For-

    mation, the London Clay, and the early Paleogene ofNorth America (Houde, 1988; Kristoersen, 1999, 2002b).Although clearly identied as palaeognathous birds by theirpalatal structure, the phylogenetic anities between lithor-nithids and other palaeognathous birds are unresolved(Houde, 1988; Dyke & van Tuinen, 2004), which is in partdue to the fact that even the exact composition of this taxon,which was considered paraphyletic by Houde (1986, 1988),is uncertain. Lithornithids are distinguished from all otherpalaeognathous birds by the plesiomorphic presence of awell-developed hallux. All named European species comefrom the London Clay, and include Lithornis Owen 1840and a taxon that was tentatively referred to Pseudocrypturus

    516 Gerald Mayr

  • Houde 1988 by Houde (1988). Lithornithids and modernTinamidae are the only known volant palaeognathous birds.Lithornithids are unknown from Middle Eocene deposits

    of Europe where another palaeognathous taxon, the Palaeo-tididae, occurs. Well-preserved skeletons of the latter birdswere discovered in the Geiseltal and in Messel (Houde &Haubold, 1987; Peters, 1988b ; Mayr, 2002 f ). The Palaeo-tididae are distinguished from the Lithornithidae, andagree with a subclade of modern ratites, i.e. Struthionidae(ostrich), Rheidae (rheas), and Casuariidae (emus and casso-waries), in the presence of well-developed supraorbitalprocesses, reduced sternal keel, presence of a scapulo-coracoid, and loss of the hallux. Whereas Houde (1986) andHoude & Haubold (1987) considered a sister-group re-lationship between Palaeotididae and Struthionidae, Peters(1988b) assumed a closer relationship with the Rheidae.However, evidence for neither hypothesis is convincing.Houde & Haubold (1987, p. 37) themselves indicated thattheir character evidence consists of trivial characters andPeters (1988b, p. 223) noted that, concerning his characters, there remain some doubts concerning the synapomorphicnature of these features . Referring to an unpublishedcladistic analysis, Dyke & van Tuinen (2004) consideredthe Palaeotididae to be the sister taxon of all modernratites, but did not present the character evidence for thishypothesis.The Remiornithidae are known from leg bones and

    few associated remains from the late Paleocene of France(Martin, 1992). The absence of an ossied supratendinalbridge on the distal tibiotarsus and the structure of thehypotarsus indicate palaeognathous anities of these birds,but their relationships to other palaeognathous birds areuncertain pending on the discovery of more material.A fragmentary large pelvis from the Middle Eocene of

    Switzerland was described as Eleutherornis helveticus by Schaub(1940), who considered it to be a ratite bird. This specimenformed the basis of the Eleutherornithidae Wetmore 1951,but the known fossils are too fragmentary to exclude thepossibility that Eleutherornis belongs to the Palaeotididae,Remiornithidae, or the anseriform Gastornithidae.

    (2 ) Neognathae

    (a ) Galliformes (landfowl )

    Crown-group Galliformes comprise the Australian Mega-podiidae (megapodes), the New World Cracidae (guans,chachalacas, and currasows), and the Phasianidae (grouse,quails, pheasants, and allies), which have a worldwidedistribution and are the only galliform taxon that occursin Europe.Galliformes are well-represented and fairly diversied in

    the Paleogene of Europe and all suciently well-preservedpre-Oligocene taxa reported so far are stem-group rep-resentatives of this taxon (contra Mlkovsky`, 2002; Dyke,2003; Dyke & van Tuinen, 2004; van Tuinen & Dyke,2004).

    Paraortygoides Mayr 2000, the earliest European galliformbird (Fig. 1), was rst described from Messel and belongsto the Gallinuloididae, a taxon that was originally erectedfor the Lower Eocene Gallinuloides wyomingensis Eastman1900 from the North American Green River Formation.Paraortygoides and Gallinuloides are clearly identied as stem-group Galliformes by the cup-like scapular articulation faceton the coracoid that also occurs in Anseriformes, the sistertaxon of Galliformes, and certainly is plesiomorphic withinneornithine birds (Mayr, 2000a ; Mayr &Weidig, 2004; Fig.1). Mlkovsky`s (2002) synonymization of Gallinuloididaeand modern Cracidae is thus without any foundation andincorrect. Mourer-Chauvire (1988a) also assigned a distaltarsometatarsus from the Upper Eocene Quercy ssurellings to the Gallinuloididae, in the genus TaoperdixMilne-Edwards 1871. As detailed by Mayr & Weidig (2004),the Upper Oligocene Taoperdix pessieti (Gervais 1862), thetype species of the genus Taoperdix, is, however, not amember of the Gallinuloididae (contra Brodkorb, 1964), andthe anities of this taxon need to be restudied. My exam-ination of the type specimens revealed that Paraortygoidesradagasti Dyke & Gulas 2002 from the London Clay isprobably a junior synonym of Argillipes paralectoris Harrison& Walker 1977 from the same locality, with which it wasnot compared by Dyke & Gulas (2002).

    Table 1. Major Paleogene European fossil localities that have yielded bird remains (see Mlkovsky`, 1996b for a complete list)

    Locality Age Kind of deposit Selected references

    Fur Formation, Denmark Latest Paleocene/Lowermost Eocene Marine Kristoersen (2002b)London Clay, England Lower Eocene Marine Harrison & Walker (1977),

    Daniels in Feduccia (1999,p. 167)

    Messel, Germany Middle Eocene Lake deposit Schaal & Ziegler (1988),Peters (1988a),Mayr (2000 f )

    Geiseltal, Germany Middle to Upper Eocene Peatbogs and small lakes Krumbiegel et al. (1983),Mayr (2002 f )

    Quercy, France Middle Eocene to Upper Oligocene Fissure llings Mourer-Chauvire (1995a,1996)

    Frauenweiler, Germany Lower Oligocene Marine Trunko & Munk (1998)Cereste, France Lower Oligocene Lacustrine Mourer-Chauvire (1996)

    The Paleogene fossil record of birds in Europe 517

  • Table 2. Temporal distribution of avian taxa in major Paleogene European fossil localities. Only taxa that are known fromsubstantial, diagnostic parts of the skeleton and dated localities are listed ; extinct taxa are indicated by a dagger. Shaded eldsindicate the temporal distribution of these taxa in Europe; shaded elds without locality entry are extrapolated from the minimumand maximum age (several taxa are known from Miocene or younger deposits). Correlation of the fossil localities with aMammalian Paleogene (MP) level is after Mlkovsky` (1996b) and Legendre & Leveque (1997). Abbreviations of localities :Au Austria ; Be Mont de Berru/Cernay les Reims, France ; Ce Cereste, France ; Eg England; En Enspel, Germany;Fl Florsheim, Germany; Fr Central France ; Fu Fur Formation, Denmark ; Fw Frauenweiler, Germany;Ga Gaimersheim, Germany; Ge Geiseltal, Germany; Ha Hampshire, England; He Herrlingen, Germany;Ho Hoogbutsel/Boutersem, Belgium; Le Leipzig area, Germany; Lo London Clay, England; Ma Matt, Switzerland;Me Messel, Germany; Mo Montmartre gypsum, France; Ne Nederokkerzeel, Belgium; Qu Quercy ssure llings,France; Si Siegsdorf, Germany; Wa Walbeck, Germany

    Paleocene

    Eocene

    Oligocene

    MP 16Lower

    Middle

    Upper Lower UpperMP 710 MP 1113 MP 1416 MP 1720 MP 2124 MP 2530

    PALAEOGNATHAE

    #Lithornithidae Lo, Fu#Palaeotididae Me, Ge#Remiornithidae (Palaeognathaeinc. sed.)

    Be

    NEOGNATHAE

    Galliformes : #Gallinuloididae Lo Me ?Qu#Quercymegapodiidae Qu Qu#Paraortygidae Qu Le, Qu QuPhasianidae Qu

    Anseriformes : #Gastornithidae Be, Wa Lo Me, Ge?Anseranatidae Lo FrPresbyornithidae ?HaAnatidae ?Ha ?Ho

    Gaviiformes : #Colymboides Ha Fw, HoProcellariiformes : #Diomedeoididae Fw, Le Fl#Pelagornithidae Eg LoPelecaniformes : #Prophaethontidae Lo Ne

    Sulidae ?Me Fr Fr, SiPhalacrocoracidae Quercy, unknown horizon En, ?Fr

    Phoenicopteriformes : #Palaelodidae Ho FrPhoenicopteridae Fr, ?Ho Fr

    #Juncitarsus MeCiconiiformes : Threskiornithidae Me Ce

    Ardeidae QuGruiformes : #Messelornithidae Be Me Qu Qu

    Rallidae ?Fr, Ha Ho, Le FrGruidae ?Ha#Elaphrocnemus Qu Qu Qu#Idiornithidae Me, Ge Qu Qu Qu, ?Ho Qu#Salmilidae Me#Ameghinornithinae Me ?Qu Qu

    Charadriiformes : #Turnipacidae Ce?Glareolidae HoScolopacidae Ce FrLaridae FrAlcidae Au

    Columbiformes : Pteroclidae QuFalconiformes : Cathartidae Qu

    Sagittariidae Qu Qu#Horusornithidae QuAccipitridae ?Ha ?Ho Fr

    Strigiformes : cf. #Tynskya, #Messelastur Lo Me#Sophiornithidae ?Be, ?Wa Quercy, unknown horizonProtostrigidae Lo Le#Palaeoglaucidae ?Me QuTytonidae ?Qu ?Qu ?Qu

    518 Gerald Mayr

  • The Quercymegapodiidae and Paraortygidae are knownfrom many well-preserved bones from the Middle to UpperEocene and Oligocene, respectively, Quercy ssure llings(Mourer-Chauvire, 1992a) and from the Lower Oligoceneof Germany (Fischer, 1990, 2003). These two taxa are alsoidentied as stem-group Galliformes by the plesiomorphicpresence of a cup-like scapular articulation facet on thecoracoid (Mourer-Chauvire, 1992a ; Fig. 1), and Mlkovsky`s(2002) synonymization of the Quercymegapodiidae withmodern Megapodiidae again is incorrect. Ludiortyx homanni(Gervais, 1852) from the Upper Eocene of Paris, classiedinto the Gallinuloididae by Brodkorb (1964) but consideredto belong to the Rallidae (rails) by Brunet (1970) andCracraft (1973), probably is a member of the Quercymega-podiidae with which it has not yet been compared (Mayr,2000a).Fragmentary remains of other putative Galliformes which

    were reported as Phasianidae from the Paleogene of

    England by Harrison & Walker (1977, 1979a, b) need to berestudied and compared with the above taxa.The earliest European crown-group galliform bird is the

    Upper Oligocene phasianid taxon Palaeortyx (Mourer-Chauvire, 1992). According to Ballmann (1969) this taxonmost closely resembles the modern Arborophila, which iswidespread in the tropical and subtropical regions of Africaand Asia, although these similarities may well be plesio-morphic within Galliformes and have not yet been eval-uated in a cladistic context.

    (b ) Anseriformes (waterfowl, incl. Gastornithidae)

    Crown-group Anseriformes include the South AmericanAnhimidae (screamers), the Australian Anseranatidae(magpie goose), and the Anatidae (swans, geese, and ducks).Only the last group today occurs in Europe.

    Table 2. (cont.)

    Paleocene

    Eocene

    Oligocene

    MP 16Lower

    Middle

    Upper Lower UpperMP 710 MP 1113 MP 1416 MP 1720 MP 2124 MP 2530

    Psittaciformes : #Pseudasturidae Lo Me, Ge#Quercypsittidae Qu#Psittacopes Lo Me

    Musophagiformes GaColiiformes : #Sandcoleidae ?Fu Me, Ge, Fr

    Coliidae Me, Ge Qu Qu Fw, HoTrogoniformes Lo, Fu Me Ce, Ma

    Caprimulgiformes s.s. : Nyctibiidae Me Quercy, unknown horizonCaprimulgidae ?Qu

    #Archaeotrogonidae ?Lo Me Qu Qu QuPodargidae Me QuApodiformes : #Eocypselidae Lo, Fu

    #Aegialornithidae Ge Qu Qu?Hemiprocnidae Qu Qu QuApodidae Me FrTrochilidae Me Fw

    ?Leptosomidae (#Plesiocathartes) Lo Me, Ge Quercy, unknown horizonCoraciiformes s.s. : #Primobucconidae Lo Me

    #Eocoraciidae Me#Geranopteridae Qu

    Alcediniformes : #Quasisyndactylus Me?Momotoidea Qu Qu, Ma

    Upupiformes : #Messelirrisoridae Lo Me, Ge#Laurillardiidae Mo

    Piciformes : #Sylphornithidae Qu ?Mo Ho#Gracilitarsidae MePici Ho He

    #Primoscenidae Lo, Fu MePasseriformes Fw, Ce Fr, QuIncertae sedis : #Palaeopsittacus Lo Me

    cf. #Fluvioviridavis1 Lo#Pumiliornis2 Me

    1 See Mayr & Daniels (2001).2 See Mayr (1999 c).

    The Paleogene fossil record of birds in Europe 519

  • The giant ightless Gastornithidae (Diatrymidae auct.,see Buetaut, 1997, and Mlkovsky`, 2002 who synonymizedGastornis Hebert 1855 and Diatryma Cope 1876) were shownto be the sister taxon of crown-group Anseriformes byAndors (1992). In Europe, gastornithids were reported fromthe Paleocene and Lower Eocene of England, France, andGermany (e.g. Fischer, 1962, 1978; Andors, 1992; Buetaut,1997). Gastornithidae also occur in the Lower Eocene ofChina (Hou, 1980) and North America, and are evidencefor the existence of a land connection between Europe andNorth America by that time (Andors, 1992).The extinct Presbyornithidae are abundant anseriform

    birds in the Paleogene of North America (Olson & Feduccia,1980a) and were identied in Europe by Harrison & Walker(1976 c, 1978) and Dyke (2001 e).From the London Clay, Olson (1999b) reported an

    anseriform species, Anatalavis oxfordi Olson 1999, that is rep-resented by most of the cranial half of the skeleton includ-ing the skull. A. oxfordi was considered by Olson (1999b) tobe most closely related to the Anseranatidae, but at least thelarge pneumatic foramen on the sternal end of the coracoid,which was listed as supporting evidence and also occurs in

    the Anhimidae, may be plesiomorphic within Anseriformes(Livezey, 1986; it is equally parsimonious to assume that thisforamen evolved in the stem species of Anseriformes andwas reduced in the Anatidae, or that it convergently evolvedin Anseranatidae and Anhimidae). A phylogenetic analysisby Dyke (2001 e) resulted in a sister-group relationship be-tween A. oxfordi and a clade including Presbyornithidae andAnatidae. However, this analysis is considerably awed bythe fact that only 22 of the 123 included characters couldbe coded for A. oxfordi, and that characters listed as evidencefor anseranatid anities of Anatalavis by Olson (1999b) werenot included, e.g. concerning the morphology of the furculathat is absolutely distinctive in being V-shaped and havinga long, broad symphysis, thus resembling only Anseranasamong the Anseriformes (Olson, 1999b, p. 241). Anatalaviswas originally described from the Upper Cretaceous or earlyPaleocene of New Jersey (Olson & Parris, 1987, see Olson,1994 for the age of this locality), and Mlkovsky` (2002)separated A. oxfordi in a new genus, Nettapterornis. I agree withMourer-Chauvire (2004) that the known material doesnot justify this action. Mlkovsky` (1996a, 2002) and Olson(1999b) noted that another anseriform, Romainvillia stehlini

    Gal

    linu

    loid

    idae

    Par

    aort

    ygid

    ae

    Qu

    ercy

    meg

    apo

    diid

    ae

    Meg

    apo

    diid

    ae

    Cra

    cid

    ae

    Ph

    asia

    nid

    ae

    1

    2

    3

    4

    10 mm

    Fig. 1. Phylogenetic relationships between Paleogene and extant taxa of the Galliformes (after Mayr & Weidig, 2004), with a gureof Paraortygoides messelensis Mayr 2000 (Gallinuloididae) from the Middle Eocene of Messel in Germany (holotype specimen). Extincttaxa are indicated by a dagger, the arrow indicates the crown-group. The nodes are supported by the following diagnosticsynapomorphies : 1 humerus with markedly elongated tuberculum dorsale ; tarsometatarsus, plantar side of articular surface oftrochlea metatarsi III asymmetric with lateral ridge protruding farther proximally than medial ridge. 2 Humerus with transversalridge at beginning of incisura capitis (weakly developed in Quercymegapodiidae). 3 Cotyla scapularis of coracoid shallow.4 Carpometacarpus with wide spatium intermetacarpale and strongly bowed os metacarpale minus.

    520 Gerald Mayr

  • Lebedinsky 1927 from the Upper Eocene of France, mayalso belong to the Anseranatidae. So far, however, no derivedcharacters have been presented which support this assump-tion, and the coracoid of Romainvillia lacks the pneumaticforamen which is characteristic for the coracoid of theAnseranatidae (Mayr & Smith, 2001). The plesiomorphic(Livezey, 1986; Olson, 1999b) presence of a foramen forthe supracoracoideus nerve, however, shows Anatalavis andRomainvillia to be outside crown-group Anatidae. A furtherputative member of the Anseranatidae, Anserpica kiliani, hasrecently been reported from the Upper Oligocene of France(Mourer-Chauvire, Berthet & Hugueney, 2004).The earliest European representative of crown-group

    Anatidae may be Paracygnopterus scotti Harrison & Walker1979 from the early Oligocene of England. The coracoidof Paracygnopterus exhibits a distinct incision for the supra-coracoideus nerve which is present in many recentAnserinae (swans and geese), but absent in Anatinae (ducks)and Dendrocygninae (whistling-ducks). Remains of Para-cygnopterus were also tentatively identied in the LowermostOligocene of Belgium by Mayr & Smith (2001). Also fromthe Oligocene of Belgium, a large anseriform taxon wasdescribed as Cygnopterus by Lambrecht (1931), who con-sidered it to be a swan. At least judging from the publishedillustrations, Cygnopterus is very similar to the presumedpresbyornithid (Dyke, 2001 e)HeadonornisHarrison &Walker1976 from the Upper Eocene of England, with which is hasnot yet been compared. Mionetta Livezey & Martin 1988,which occurs in the Upper Oligocene of France (Hugueneyet al., 2003), was shown to occupy a basal position withincrown-group Anatidae by Livezey & Martin (1988).

    ( c ) Gaviiformes (loons) and Procellariiformes (tubenoses and petrels)

    In Europe, the earliest record of Gaviiformes is Colymboidesanglicus Lydekker 1891 from the Upper Eocene of England(Storer, 1956). This species is represented by a coracoid, areferred humerus, and a referred frontal part of the skull(Harrison & Walker, 1976 c). Another species of Colymboides,Colymboides belgicus, was described from the lowermostOligocene of Belgium and is based on a proximal carpo-metacarpus and a distal ulna (Mayr & Smith, 2002b).Recently, a disarticulated skeleton of a new species ofColymboides, C. metzleri Mayr 2004, was also found in theLower Oligocene of Frauenweiler (Mayr, 2004a). In thisspecimen stomach content is preserved, which showsPaleogene loons to be piscivorous like their modern rela-tives. Remains of Colymboides are also known from earlyMiocene deposits (Storer, 1956). Storer (1956, p. 423) notedthat the hindlimbs of Colymboides were not as highly adaptedfor swimming rapidly and powerfully under water as arethose of living loons , and that the morphological dier-ences between Colymboides and Gavia are many and rathergreat, but they are largely one of size and degree of special-ization (p. 425).The earliest European remains of putative procellariiform

    birds were reported from the London Clay (Harrison &Walker, 1977) but these, a distal end of a humerus describedas Primodroma bournei Harrison & Walker 1977 and a frag-mentary beak and proximal end of a carpometacarpus

    described as Marinavis longirostris Harrison & Walker 1977,are too fragmentary for reliable identication (see alsoSteadman, 1981; Mlkovsky`, 2002, p. 259). The earliestEuropean record of procellariiform birds thus is the Dio-medeoididae which are known from abundant remains,including several complete skeletons, from the LowerOligocene (Rupelian) of Germany, France, and Belgium,and the Upper Oligocene of Germany (Cheneval, 1995;Mayr, Peters & Rietschel, 2002). Diomedeoididae werefurther reported from the Oligocene of Iran (Peters &Hamedani, 2000). These birds are characterized by apeculiar foot structure with grotesquely widened phalanges,which are strikingly similar to those of the modernprocellariiform Nesofregetta (Hydrobatidae, storm petrels). Inother respects, however, the skeleton of the Diomedeoididaestrongly diers from all Hydrobatidae, and their phylogen-etic anities to other procellariiform birds are uncertain(Mayr et al., 2002).Larus raemdonckii van Beneden 1871, known from an

    incomplete humerus from the Rupelian of Belgium, wasplaced in the genus Punus by Brodkorb (1962), but alsoneeds to be compared with the Diomedeoididae.

    (d ) Pelagornithidae (bony-toothed birds)

    The extinct, bony-toothed Pelagornithidae are fairly abun-dant and greatly diversied in Paleocene and Lower Eocenemarine deposits of England (Harrison & Walker, 1976b,1977; Harrison, 1985). However as noted by Olson (1985),the taxonomy of these birds, which at this locality areknown from isolated remains only, is in dire need of revisionand probably too many taxa are currently recognized.The large tarsometatarsi from the London Clay that wereassigned to the alleged procellariiform Neptuniavis byHarrison & Walker (1977) almost certainly belong to oneof the pelagornithid taxa from the same locality, of whichthe tarsometatarsus has not been described (Mayr et al.,2002, see also Harrison & Walker, 1976b, p. 60). The sys-tematic anities of the Pelagornithidae are still uncertainand anities to Procellariiformes and Pelecaniformeswere suggested (Harrison & Walker, 1976b ; Olson, 1985).Pelagornithidae also occur in the Paleocene to earlyOligocene of the former USSR (e.g. Averianov et al., 1997;Aslanova & Burchak-Abramovich, 1999), the Eocene ofNigeria (see Rasmussen, Olson & Simons, 1987), and theNeogene of Europe, Japan, North and South America,Antarctica, and New Zealand (Olson, 1985; Ono,Hasegawa & Kawakami, 1985; Cheneval, 1993).

    ( e ) Pelecaniformes ( pelicans, cormorants, and allies)

    The most completely preserved Paleogene pelecaniformbird from Europe is Prophaethon shrubsolei Andrews 1899, thesingle named species of the extinct Prophaethontidae, ofwhich a partial skeleton has been found in the London Clay(Harrison & Walker, 1976a) and a coracoid in MiddleEocene marine deposits of Belgium (Mayr & Smith, 2002a).Prophaethontidae were also tentatively identied in thePaleocene of North America (Olson, 1994), and exhibit amosaic of derived characters of modern Pelecaniformes

    The Paleogene fossil record of birds in Europe 521

  • (e.g. presence of an articulation facet for the furcula onthe sternal carina and a distinct naso-frontal hinge) andProcellariiformes (e.g. narrow pelvis and enlarged cnemialcrests on tibiotarsus). Compared to modern birds, theProphaethontidae most closely resemble the pelecaniformPhaethontidae (tropicbirds), but their phylogenetic assign-ment is aggravated by the existing uncertainty regardingmonophyly of the traditional Pelecaniformes (e.g. Sibley &Ahlquist, 1990; van Tuinen et al., 2001; Mayr, 2003d ).There is no Paleogene European record of Pelecanidae

    (pelicans), as Protopelicanus cuvieri Reichenbach 1852 wasincorrectly identied (Olson, 1985, contra Brunet, 1970).Phalacrocoracidae (cormorants) are known from the

    Upper Oligocene of Germany (Mayr, 2001a) and France(Mourer-Chauvire et al., 2004) and were also reportedfrom the Quercy ssure llings (Mourer-Chauvire, 1995a).The Oligocene taxa appear to be outside crown-groupPhalacrocoracidae (Mayr, 2001a). The coracoid of BorvocarboMourer-Chauvire et al., 2004, from the Upper Oligocene ofFrance, diers from that of extant Phalacrocoracidae andAnhingidae, their sister taxon, in the presence of a plesio-morphic, cup-like cotyla scapularis and Borvocarbo may thuseven be outside the clade (Phalacrocoracidae+Anhingidae).Sulidae (gannets and boobies) were reported from the

    Oligocene of Germany (Darga et al., 1999) and France(Mourer-Chauvire, 1995a). Masillastega Mayr 2002 fromMessel is known from an isolated skull only and was tenta-tively identied as a stem-group representative of theSulidae (Mayr, 2002d ).

    ( f ) Charadriiformes (shorebirds, incl. Turnicidae)

    Charadriiform birds have a scanty Paleogene record inEurope. Taxa that are unambiguously within crown-groupCharadriiformes are not known from pre-Oligocene de-posits. The Lower Eocene taxa that were reported fromthe London Clay consist of very fragmentary remains andare in need of revision; the paratypic humerus of the puta-tive pratincole (Glareolidae) Precursor parvus Harrison &Walker 1977, for example, belongs to the psittaciformPseudasturidae (Mayr, 2002g). A partial skeleton of anunnamed species of uncertain anities within Charadrii-formes was described from Messel (Mayr, 2000 e), but istoo incompletely preserved to allow detailed comparisons.Scolopacidae (sandpipers, snipes, and allies) were reportedfrom the Lower Oligocene of Cereste (Roux, 2002), from anunknown horizon of the Quercy ssure llings (Totanus edwardsi Gaillard 1908), and from the Upper Oligocene ofFrance (Hugueney et al., 2003). The two species of VilletusHarrison & Walker 1976 from the Upper Eocene ofEngland are based on distal tibiotarsi and cannot be referredto the Scolopacidae with condence (contra Harrison &Walker, 1976 c).An as yet unnamed charadriiform bird from the Lower

    Oligocene of Southern France was gured and briey de-scribed by Bessonat & Michaut (1973). The anities ofthis specimen, which is in a private collection in France,are uncertain, but judging from the apparently complete ab-sence of a hallux it may belong within Charadriidae (ploversand allies). Boutersemia Mayr & Smith 2001 from the Lower

    Oligocene of Belgium is known from several postcranialelements of two species and was tentatively assigned to theGlareolidae (pratincoles), but this assignment was based ona possibly plesiomorphic overall similarity (Mayr & Smith,2001). Laridae (gulls) are known from the Upper Oligoceneof France (Hugueney et al., 2003; Mourer-Chauvire et al.,2004; the putative gull Gaviota lipsiensis Fischer 1983 belongsto the procellariiform Diomedeoididae, see Mayr et al.,2002). The earliest European record of Alcidae (auks) is adissociated skeleton from the Upper Oligocene of Austria(Mlkovsky`, 1987).The Turnipacidae were described from the Lower

    Oligocene of Cereste (Mayr, 2000 e) and include TurnipaxMayr 2000 and the tentatively referred CeresteniaMayr 2000.Mayr (2000 e) assigned these birds to the Charadriiformesbut noted similarities to the Turnicidae (buttonquails), in-cluding a highly derived coracoid morphology. If Turnicidaeare indeed within crown-group Charadriiformes as assumedby Paton et al. (2003), the Turnipacidae may be on theirstem-lineage and the similarities to charadriiform birdsplesiomorphic for the clade including Charadriiformes andTurnicidae.

    (g ) Columbidae (doves and pigeons) and Pteroclidae (sandgrouse)

    Columbidae have no Paleogene fossil record, even outsideEurope, and I consider the Lower Eocene putative columbidMicroena Harrison & Walker 1977 to be a member of theCypselomorphae. Olson (1989) assumed that Columbidaeevolved in the Southern Hemisphere and did not arrivein Europe before the Neogene. Pteroclidae, however,were found in the Quercy ssure llings (Mourer-Chauvire,1992b, 1993) : Archaeoganga Mourer-Chauvire 1992 was re-ported from an unknown horizon and locality and LeptogangaMourer-Chauvire 1993 from Upper Oligocene deposits.At least Leptoganga exhibits the peculiar intermetatarsalsesamoid bone that is characteristic of modern Pteroclidae(Mourer-Chauvire, 1993).

    (h ) Threskiornithidae (ibises), Ardeidae (herons), andCiconiidae (storks)

    The earliest substantial European fossil record of theThreskiornithidae is Rhynchaeites messelensis Wittich 1898from Messel. This species is known from several completeand well-preserved skeletons and, among other character-istics, diers from its modern relatives in sternal morphologyand a much more abbreviated tarsometatarsus (Peters,1983; Mayr, 2002a). Roux (2002) further described an asyet unnamed species of the Threskiornithidae from theLower Oligocene of Cereste, which also exhibits a pro-portionally shorter tarsometatarsus than modern ibises. Allother Paleogene ibises are based on much too fragmentaryremains for reliable identication (see Olson, 1981).The only substantial Paleogene record of Ardeidae

    from Europe is Proardea amissa that was described from anunknown horizon and locality of the Quercy ssure llingsby Milne-Edwards (1892). New remains of P. amissa werefound in the Upper Oligocene Quercy locality Pech Desse(C. Mourer-Chauvire, personal communication; G. Mayr,

    522 Gerald Mayr

  • personal observations). According to Mlkovsky` & Svec(1989), Anas basaltica Bayer 1883 from the Lower Oligoceneof the Czech Republic is another member of the Ardeidae.Ciconiidae (storks) have not been recorded from the

    Paleogene of Europe and their earliest record is from theUpper Eocene of Egypt (Miller, Rasmussen & Simons,1997).

    ( i ) Phoenicopteriformes ( amingos)

    The phylogenetic anities of the Phoenicopteriformes havelong been debated (see reviews in Olson & Feduccia, 1980band Sibley & Ahlquist, 1990). Recent molecular and mor-phological studies, however, provide strong evidence for asister-group relationship to Podicipediformes (grebes) (vanTuinen et al., 2001; Chubb, 2004; Mayr, 2004b), which putsinto a new light some fossil taxa that were assigned to thePhoenicopteriformes.The earliest fossils classied into the Phoenicopteriformes

    belong to the Middle Eocene Juncitarsus that was originallydescribed fromNorth American deposits (Olson & Feduccia,1980b), but subsequently also reported from Messel (Peters,1987b). The phylogenetic position of Juncitarsus is in need ofrevision, as this taxon lacks most of the derived charactersthat support sister-group relationship between amingosand grebes and thus could at best be the sister-group of aclade including the latter two taxa (Mayr, 2004b). Kashinia(Tenuicrus ) magna, from the Upper Eocene of England(Harrison & Walker, 1976 c), was assigned to the Juncitar-sinae by Mlkovsky` (2002), but the coracoid of this speciesdistinctly diers in its proportions from the correspondingbone of the Juncitarsinae as gured by Ericson (1999).The Palaelodidae are an extinct taxon of phoenicopterid

    birds that is fairly abundant in the Upper Oligocene ofFrance (Mourer-Chauvire, 1995a) and was also reportedfrom the Lower Oligocene of Belgium (Mayr & Smith,2002b). These aquatic birds provide a morphological linkbetween Phoenicopteriformes and Podicipediformes, incombining the deep mandibular rami of modern amingoswith leg bones that show many similarities with those ofa foot-propelled diving bird such as Podiceps (Cheneval& Escuillie, 1992, p. 218). Palaelodids trenchantly dier,however, from modern amingos in the plesiomorphicpresence of a short and straight beak (Cheneval & Escuillie,1992).The earliest fossil assigned to the Phoenicopteridae, i.e.

    the most inclusive taxon to which modern amingos butnot the Palaelodidae belong, is Elornis Milne-Edwards186771 from the Lowermost Oligocene of Ronzon inFrance. Elornis is too incompletely known to assess its exactphylogenetic position, but is likely to be outside crown-group Phoenicopteridae, as even early Miocene amingosstill exhibit a less derived bill morphology than their extantrelatives (Feduccia, 1999, p. 202).

    ( j ) Gruiformes (cranes, rails, and allies)

    Various fossil taxa have been assigned to the, almostcertainly paraphyletic (e.g. Mayr & Clarke, 2003),Gruiformes . An abundant group of these are the

    Messelornithidae, which are known from Paleocene toLower Oligocene deposits of Germany and France (Hesse,1990; Mourer-Chauvire, 1995 c). These birds were con-sidered to be most closely related to the South AmericanEurypygidae by earlier authors (Hesse, 1990; Livezey,1998). However, this hypothesis has not been well estab-lished and I consider messelornithids to be the sister taxon ofthe clade (Heliornithidae+Rallidae), with which they sharederived characters such as absence of pneumatic foraminaon the proximal humerus and a derived morphology of thecoracoid and hypotarsus (Mayr, 2004 e). Messelornithidaeare also known from the Lower Eocene of North America(Hesse, 1992).Several putative true Rallidae (rails) were described

    from the London Clay (Harrison &Walker, 1977; Harrison,1984b) but the identication of these fragmentary remainsis questionable ; specimens assigned to PediorallusHarrison &Walker 1977 were identied as remains of the palaeo-gnathous Lithornithidae by Houde (1988). Ibidopsis Lydekker1891 from the Upper Eocene of England and Quercyrallusquercy Cracraft 1973 from the Quercy ssure llings appearto have been correctly identied but are also known fromfew bones only (see Cracraft, 1973; Harrison & Walker,1976 c ; Olson, 1977b). The earliest substantial records ofRallidae are Rupelrallus Fischer 1997 and Belgirallus Mayr& Smith 2001 from the Lower Oligocene of Germanyand Belgium, respectively (Fischer, 1997; Mayr & Smith,2001).Gruidae (cranes) were reported from the Middle Eocene

    of Italy (Palaeogrus princeps Portis 1884) and the UpperEocene of England [Geranopsis hastingsiae Lydekker 1891 andPalaeogrus hordwelliensis (Lydekker 1891)], but their identi-cations are based on fragmentary or poorly preserved re-mains and need to be conrmed by additional specimens.Judging from the illustrations, the coracoid of Geranopsishastingsiae resembles that of the putative anseranatid Anserpica(see above).A diverse group of gruiform birds in the Paleogene of

    Europe are the Idiornithidae. These medium-sized to largecursorial birds are the sister taxon of a clade includingthe extinct New World Phorusrhacidae and the modernSouth American Cariamidae (seriemas) (Mourer-Chauvire,1983a ; Mayr, 2002 c). Idiornithid remains are especiallyabundant in the Quercy ssure llings (Mourer-Chauvire,1983a) but were also reported from Messel and the Geiseltal(Peters, 1995; Mayr, 2000g, 2002 f ). As noted by Mayr(2002 f ), the putative hornbill Geiseloceros Lambrecht 1935from the Geiseltal also belongs into the Idiornithidae. Of theidiornithid taxa currently recognized (Mourer-Chauvire,1983a), Elaphrocnemus lacks derived characters that areshared by Idiornis and modern Cariamidae, such as thefusion of the procoracoid and acrocoracoid process ofthe coracoid and a block-like hypotarsus (Mayr, 2002 c). Therelationship of Elaphrocnemus need to be restudied, especiallyas Mourer-Chauvire (1983a) also noted similarities to theSouth American Opisthocomidae (hoatzin).Alvarenga & Hoing (2003) recently showed convinc-

    ingly that the alleged European Phorusrhacidae (Mourer-Chauvire, 1981; Peters, 1987a) do not belong withinPhorusrhacidae. Both species, from Quercy and Messel,

    The Paleogene fossil record of birds in Europe 523

  • were recently assigned to the genus Strigogyps Gaillard 1908(Mayr, 2005b).The enigmatic Middle Eocene Salmilidae Mayr, 2002 c

    are known from excellently preserved skeletons from Messel(Mayr, 2000d, 2002 c) and share derived characters mainlywith the Cariamae (to which the extant Cariamidae belong)and the Psophiidae (trumpeters). Their exact systematicanities are however unknown, pending on a reliablephylogenetic framework of crown-group Gruiformes.

    (k ) Falconiformes (diurnal birds of prey)

    As traditionally recognized (e.g. sensu Wetmore, 1960),crown-group Falconiformes comprise Cathartidae (NewWorld vultures), Sagittariidae (secretary bird), Falconidae(falcons), and Accipitridae (hawks and allies), but monophylyof this taxon is weakly supported and has been doubted byseveral recent authors (see discussions in Olson, 1985; Sibley& Ahlquist, 1990; Mayr, Manegold & Johansson, 2003).Cathartidae were reported from the Quercy ssure

    llings (Mourer-Chauvire, 2002) and include DiatropornisOberholser 1899 and Parasarcoramphus Mourer-Chauvire2002. OligocathartesHarrison & Walker 1979 from the LowerOligocene of England is based on such fragmentary remains(a distal tarsometatarsus lacking two trochleae) that a re-liable identication is not possible, especially given the fairlyundiagnostic morphology of the distal tarsometatarsus ofthe Cathartidae. Plesiocathartes Gaillard 1908 was removedfrom the Cathartidae (Mourer-Chauvire, 2002; Mayr,2002b) and probably is a stem-group Leptosomidae (cuckoo-rollers) (Mayr, 2002b). The earliest New World record ofthe Cathartidae is from the late Oligocene of Brazil(Alvarenga, 1985).Sagittariidae were reported from the Oligocene of

    France. The single known taxon, Pelargopappus Stejneger1885, was considered to be too evolved to be the ancestorof recent Sagittariidae (Mourer-Chauvire & Cheneval,1983, p. 443). The more accipitrid -like morphology ofPelargopappus (e.g. tarsometatarsus with a more strongly de-veloped trochlea for the second toe and a more pronouncedmedial hypotarsal crest) may, however, turn out to representthe primitive condition in Sagittariidae, as some recentphylogenetic studies support a sister-group relationshipbetween Sagittariidae and Accipitridae (Sibley & Ahlquist,1990; Griths, 1994; Fain & Houde, 2004; contra, however,Mayr & Clarke, 2003).An extinct taxon of falconiform birds, the Horusorni-

    thidae Mourer-Chauvire 1991, occurs in the Upper EoceneQuercy ssure llings and is known from numerous iso-lated postcranial bones (Mourer-Chauvire, 1991). Amongother features (Mourer-Chauvire, 1991), horusornithidsshare with modern Accipitridae and Falconidae a derivedmorphology of the hypotarsus, which exhibits two markedcrests that are separated by a wide sulcus. Horusornithidaeand most Accipitridae further share a derived modicationof the major metacarpal of the carpometacarpus (seeMourer-Chauvire, 1991), but dier from other falconi-form birds and agree with owls in the absence of an ossiedsupratendinal bridge on the distal tibiotarsus. Their exactrelationships to other falconiform birds still are uncertain.

    Two species of the Accipitridae were further described byMilne-Edwards (1892) and Gaillard (1939) from unknownlocalities and horizons of the Quercy ssure llings (Aquila hypogaea Milne-Edwards 1892 and Aquila corroyi Gaillard1939), and Mayr & Smith (2002b) tentatively assigned adistal tarsometatarsus from the Lower Oligocene of Belgiumto the Accipitridae.From deposits in England, the Lower Eocene

    Parvulivenator Harrison 1982a and Stintonornis Harrison 1984were assigned to the Falconidae (Harrison, 1982a, 1984b),the Upper Eocene Milvoides Harrison and Walker 1979was considered to be a member of the Accipitridae. Thesethree taxa are based on distal, partly fragmentary tarso-metatarsi, and at least the tiny Parvulivenator is almostcertainly not a falconiform bird. I identied a secondspecimen of Parvulivenator watteli Harrison 1984, also fromthe London Clay, in the collection of the Natural HistoryMuseum in London (specimen BMNHA 6161) and nd thisspecies to be more similar to Coliiformes (mousebirds).Stintonornis and Milvoides appear to have been correctly re-ferred to the Falconiformes , but the fragmentary remainsdo not allow a reliable assignment to any subgroup withinthis taxon.

    ( l ) Strigiformes (owls)

    The fossil record of Strigiformes goes back into thePaleocene and is quite extensive in Eocene and Oligocenedeposits of Europe, although the relationships betweenthe fossil and the modern taxa (i.e. Tytonidae, barn owls,and Strigidae, true owls) are only insuciently resolved.The Sophiornithidae were originally erected for Sophiornis

    Mourer-Chauvire 1987, from an unknown locality andhorizon of the Quercy ssure llings. Subsequently,Berruornis Mourer-Chauvire 1994 from the Paleocene ofGermany and France was also assigned to this taxon(Mourer-Chauvire, 1994; Mayr, 2002 e), as well as PalaeotytoMourer-Chauvire 1987 and Palaeobyas Mourer-Chauvire1987 from the Quercy (Mlkovsky`, 2002). Sophiornithidaewere considered stem-group representatives of theStrigiformes by Mourer-Chauvire (1987, her Fig. 8).The Protostrigidae, rst reported from the Paleogene

    of North America (e.g. Wetmore, 1933; Martin & Black,1972; Mourer-Chauvire, 1983b), are represented in Europeby Oligostrix Fischer 1983 and Eostrix Harrison 1980(Harrison, 1980; Fischer, 1983). The Protostrigidae are well-characterized by the derived presence of a greatly widenedmedial condyle of the tibiotarsus and, apparently function-ally correlated therewith, a strongly developed rst andsecond toe. The Protostrigidae were also considered to beoutside crown-group Strigiformes by Mourer-Chauvire(1987, her Fig. 8) and derived characters shared by crown-group Strigiformes but absent in the Protostrigidae are themedially situated tubercle for the tibialis anticus muscle onthe proximal tarsometatarsus (Mourer-Chauvire, 1983b,her Fig. 2) and the unusually slender humerus (Howard,1965).An articulated postcranial skeleton of an owl from Messel

    was assigned to PalaeoglauxMourer-Chauvire 1987 by Peters(1992), who considered the possibility that it represents the

    524 Gerald Mayr

  • rst evidence of Eocene strigids (p. 168). The Messel owl is,however, clearly distinguished from crown-group Strigi-formes by the absence of an osseous arch on the radius, aderived feature of modern owls (Bock & McEvey, 1969;Fig. 4 in Peters, 1992).All other Paleogene owls, which come mainly from Upper

    Eocene to Oligocene deposits of the Quercy ssure llings,were assigned to the Tytonidae (Mourer-Chauvire, 1987;Mlkovsky`, 1998). However, this assignment is based onthe plesiomorphic absence of an ossied arcus extensoriuson the proximal tarsometatarsus and a deep supracondylarfossa on the distal tibiotarsus. Thus some, if not all,Paleogene taxa that are currently assigned to the Tytonidaemay well be stem-group representatives of either Strigi-formes or Strigidae.

    Tynskya eocaena was described by Mayr (2000 c) from theLower Eocene North American Green River Formation,and bones of a closely related species were also found in theLondon Clay. The tarsometatarsus of T. eocaena exhibits aderived morphology similar to that of strigiform birds in thatthe medial crest of the hypotarsus is markedly longer thanthe lateral crest, and the trochlea for the fourth toe muchshorter than that for the second, bearing a plantarly pro-jecting wing-like ange which is typical of semi-zygodactylfeet in which the fourth toe can be spread laterally. Contraryto owls however, T. eocaena lacks a derived enlarged trochleafor the second toe and the humerus is not as slender andelongated. T. eocaena was recently shown to be the sistertaxon of Messelastur gratulator Peters 1994 (Mayr, in press),which was tentatively assigned to the Accipitridae by Peters(1994). An as yet undescribed, almost complete skeleton ofM. gratulator shows that this species diers from all modernbirds of prey and agrees with owls in the absence of a supra-tendinal bridge on the distal tibiotarsus (Mayr, in press).Cladistic analysis of 110 characters supports a sister-grouprelationship between Messelastur and Tynskya, and shows

    both taxa to be the sister-group of strigiform birds (Mayr,in press).

    (m ) Psittaciformes ( parrots)

    In recent years, several stem-group Psittaciformes weredescribed from Eocene deposits in England, Germany, andFrance that are successive sister taxa of crown-groupPsittaciformes.The most basal taxon of these are the Pseudasturidae

    (Fig. 2) that were reported from the London Clay, Messel,the Geiseltal, and the North American Green RiverFormation (Dyke & Cooper, 2000; Dyke, 2001b ; Mayr,2002 f, g ;). These birds distinctly dier from crown-groupPsittaciformes and were originally considered to be ofuncertain anities (Mayr, 1998a), but especially the three-dimensionally-preserved London Clay specimens haveallowed establishment of their psittaciform anities (Mayr,2002g).Another taxon of stem-group Psittaciformes, Psittacopes

    Mayr & Daniels 1998 (Fig. 3), occurs in the London Clay

    Fig. 2. Pulchrapollia gracilis Dyke & Cooper 2000 (Psittaci-formes, Pseudasturidae). Selected bones of a single individualfrom the Lower Eocene London Clay at Walton-on-the-Naze(private collection of M. Daniels, from Mayr & Daniels, 1998).Scale bar in millimeters.

    Fig. 3. Psittacopes lepidus Mayr & Daniels 1998 (holotype), asmall psittaciform bird from the Middle Eocene of Messel inGermany. Scale bar in millimeters.

    The Paleogene fossil record of birds in Europe 525

  • and Messel and, of the known Paleogene Psittaciformes,appears to be most closely related to modern parrots withwhich it shares a derived accessory trochlea for the retro-verted fourth toe (Mayr & Daniels, 1998). Both Pseuda-sturidae and Psittacopes are, however, clearly shown to beoutside crown-group Psittaciformes by the plesiomorphicabsence of a parrot-like beak.The third Paleogene psittaciform taxon, the Quercypsit-

    tidae, is known from the Upper Eocene of the Quercy ssurellings (Mourer-Chauvire, 1992 c). The beak of these birdsis unknown, but their coracoid exhibits a plesiomorphic,cup-like scapular articulation facet (Mourer-Chauvire,1992 c), which supports their placement outside crown-group Psittaciformes (Mayr, 2002g).After discovery of more completely preserved remains,

    the Lower Eocene Palaeopsittacus, described as a parrot byHarrison (1982 c), turned out to be an anisodactyl bird notrelated to parrots (Mayr & Daniels, 1998). An articulatedpostcranial skeleton of this bird was recently described fromMessel (Mayr, 2003b) and shows similarities to Podargidae(frogmouths) (see below).

    (n ) Coliiformes (mousebirds)

    Coliiformes today only occur with six very similar speciesin Africa south of the Sahara, but are fairly abundantand diversied in early Eocene localities. A distinctive

    taxon are the Sandcoleidae which were originally describedfrom the Paleocene and early Eocene of North America(Houde & Olson, 1992), but are also known from theMiddle Eocene of Germany and France (Mayr & Peters,1998; Mayr, 2001 e, 2002 f ; Mayr & Mourer-Chauvire,2004). The single named European sandcoleid species isEoglaucidium pallas Fischer 1987, which was originally de-scribed as an owl (Fischer, 1987, see Mayr & Peters, 1998)and is very similar to the North American Sandcoleus Houde& Olson 1992 and Anneavis Houde & Olson 1992 (Mayr &Peters, 1998).

    Eocolius walkeri Dyke & Waterhouse 2001 from theLondon Clay is most similar to Selmes absurdipes Peters 1999from Messel, and may even be a junior synonym of thisspecies. Dyke & Waterhouse (2001) could make their com-parisons only with the badly attened holotype of S. absur-dipes, but a new specimen of the latter species from Messel(Mayr, 2001 e) shows that E. walkeri cannot be distinguishedfrom S. absurdipes by the characters given by Dyke &Waterhouse (2001, p. 10). An isolated tarsometatarsus ofSelmes was also reported from the Quercy ssure llings(Mayr & Mourer-Chauvire, 2004) and provides evidencethat Selmes is a stem-lineage representative of the Coliidae,not a sandcoleid bird as assumed in the original description(Peters, 1999).Another record of the Coliidae is Masillacolius brevidactylus

    Mayr & Peters 1998, which is known from two articulated

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    Fig. 4. Phylogenetic relationships between Paleogene and extant taxa of the Coliiformes (after Mayr & Peters, 1998; Mayr &Mourer-Chauvire, 2004), with a gure of Masillacolius brevidactylus Mayr & Peters 1998 (Coliidae, holotype specimen) from theMiddle Eocene of Messel in Germany. Extinct taxa are indicated by a dagger, the arrow indicates the crown-group. The nodes aresupported by the following diagnostic synapomorphies : 1 ulna, cotyla ventralis very large ; femur, distal end thickened with largetuberculum musculi gastrocnemialis lateralis ; tibiotarsus, both cristae cnemiales and crista patellaris forming a continuous ridge thatcircumscribes a groove on the cranial side of the bone, crista cnemialis cranialis continuous with a ridge opposite to crista bularis ;tarsometatarsus, fossa metatarsi I situated on medial side of shaft ; proximal phalanges of fourth toe strongly abbreviated. 2 Discuspygostyli very large ; hypotarsus with large canal for tendon of musculus exor digitorum longus. 3 Tarsometatarsus, trochleaemetatarsorum small, not widely splayed from trochlea metatarsi III. 4 Humerus with marked, crescent-shaped depression abovecondylus dorsalis ; carpometacarpus with well-developed processus intermetacarpalis.

    526 Gerald Mayr

  • postcranial skeletons from Messel (Fig. 4), and whichapparently had pamprodactyl feet, i.e. the hallux perma-nently directed forwards as in some modern swifts. TheUpper Eocene PrimocoliusMourer-Chauvire 1988, the LowerOligocene Oligocolius Mayr 2000, and extant mousebirdsform a monophyletic taxon that is characterized by the de-rived presence of a well-developed intermetacarpal processon the carpometacarpus (Mourer-Chauvire, 1988a ; Mayr,2000b, 2001 e ; Fig. 4). A very fragmentary tarsometatarsusof a mousebird was also reported from the LowermostOligocene of Belgium (Mayr & Smith, 2001).

    (o ) Musophagidae (turacos) and Cuculidae (cuckoos)

    The only European record of Musophagidae is fromthe late Oligocene of Bavaria in Germany (Ballmann, 1970),as the alleged London Clay musophagid PromusophagaHarrison & Walker 1977 was shown to be a member ofthe Lithornithidae by Houde (1988).Cuculidae (cuckoos) do not have an unambiguous

    Paleogene European fossil record. Whether DynamopterusMilne-Edwards 1892, known from two humeri of twospecies from an unknown horizon of the Quercy ssurellings, is a member of the Cuculidae (Mourer-Chauvirein Olson, 1985, p. 110), needs to be conrmed by additionalskeletal elements. The earliest record of the Cuculidae isfrom the Lower Oligocene of North America (Weigel, 1963;Chandler, 1999).

    (p ) Leptosomidae (cuckoo-rollers) and Podargidae ( frogmouths)

    PlesiocathartesGaillard 1908, a taxon known from the Quercy(Mourer-Chauvire, 2002), Messel (Mayr, 2002b), and theGeiseltal (Mayr, 2002 f ) was removed from the Cathartidaeby Mourer-Chauvire (2002), and the complete skeletonsfrom Messel suggest a sister-group relationship to theMadagascan Leptosomidae (Mayr, 2002b). There is noother known fossil member of Leptosomidae.Podargidae were reported from the Quercy (Mourer-

    Chauvire, 1989b) and from Messel (Mayr, 1999b, 2001d ).The French taxon, Quercypodargus Mourer-Chauvire 1989,diers from modern Podargidae in the morphology ofthe distal tibiotarsus (Mayr, 1999b) but is very similar toPalaeopsittacus Harrison 1982 from the London Clay (com-pare Fig. 2 in Mourer-Chauvire, 1989b and Fig. 1 in Mayr,2003b). Derived features shared by both taxa include a wideintercondylar incision on the distal tibiotarsus (not presentin modern Podargidae) and the presence of two hypotarsalforamina, one of which is however not completely closedin Quercypodargus. Contrary to modern Podargidae, thecoracoid of Palaeopsittacus exhibits a foramen for the supra-coracoideus nerve (Fig. 1 in Mayr, 2003b ; the coracoid ofQuercypodargus is unknown). Nevertheless, in other featuresQuercypodargus and Palaeopsittacus closely resemble modernPodargidae (Mourer-Chauvire, 1989b ; Mayr, 2003b) andmay be on the stem-lineage of this taxon. The species fromMessel, Masillapodargus Mayr 1999, is known from articu-lated skeletons that preserve the highly derived beakmorphology of frogmouths.

    (q ) Cypselomorphae (aerial insectivores and hummingbirds)

    Most modern non-passeriform aerial insectivores belongto the Cypselomorphae, i.e. a monophyletic (Mayr, 2002h ;Mayr et al., 2003) taxon including Caprimulgidae (nightjars),Nyctibiidae (potoos), and apodiform birds (swifts and hum-mingbirds). Today only the Caprimulgidae and the apo-diform Apodidae (true swifts) are found in Europe, butaerial insectivores were very diversied in the EuropeanPaleogene.Nyctibiidae, which today only occur in South and Central

    America, were reported from the Quercy ssure llings(Mourer-Chauvire, 1989b) and from Messel (Mayr, 1999b,2001d ; Mayr & Manegold, 2002). The taxon from Messel,Parapreca Mayr 1999, shows the highly derived skull andtarsometatarsus morphology of modern Nyctibiidae, but isclearly identied as a stem-lineage representative by itsotherwise less derived osteology (Mayr, 1999b, 2001d ;Fig. 5). The French taxon, Euronyctibius Mourer-Chauvire1989, is known from an incomplete but very distinctivehumerus. The only Paleogene European record of theCaprimulgidae are two coracoids from the Quercy (Mourer-Chauvire, 1988a) ; identication of these bones needsfurther conrmation by additional skeletal elements. LowerEocene Caprimulgidae were reported by Olson (1999a, p. 7)from North America.Two cranial parts of sterna from the Quercy deposits

    were further tentatively identied as belonging to an oilbird(Steatornithidae) and an owlet nightjar (Aegothelidae)(Mourer-Chauvire, 1982). Certainly, these identicationsneed to be corroborated by additional skeletal elements, asthe sternum of many Paleogene birds still is unknown.An extinct group of aerial insectivores, the Archaeo-

    trogonidae, are among the most abundant small birds in theLower Oligocene Quercy ssure llings (Mourer-Chauvire,1980), and have also been reported from Messel (Mayr,1998 c). Originally considered to be trogons, archaeotrogonswere recently recognized as being related to the Cypselo-morphae (Mourer-Chauvire, 1995b). The alleged swiftLaputavis robusta (Dyke, 2001a, c ; Mayr, 2001g) from theLondon Clay may also be a representative of the Archae-otrogonidae, most similar to the Messel species Hassiavislaticauda Mayr 1998.The Eocypselidae, which were rst described by Harrison

    (1984a) from the London Clay, are outside crown-groupApodiformes (Mayr, 2003 c ; see also Dyke, Waterhouse &Kristoersen, 2004). The same is true for the Aegialor-nithidae (Mourer-Chauvire, 1988b ; Mayr, 2003 c), whichare among the most abundant small birds in the UpperEocene deposits of the Quercy ssure llings but disappeartowards the Lower Oligocene (Mourer-Chauvire, 1980).The earliest record of the Aegialornithidae is from theMiddle Eocene of the Geiseltal (Peters, 1998).Stem-group Apodidae rst occur in the Middle Eocene of

    Denmark (Harrison, 1984a) and in Messel (Mayr & Peters,1999; Fig. 5), crown-group Apodidae were reported fromthe late Oligocene of France (Mourer-Chauvire et al., 2004).The putative crown-group swift Cypseloides mourerchauvireae(Cypseloides is a modern genus), which was described byMlkovsky` (1989) on the basis of an isolated tibiotarsus

    The Paleogene fossil record of birds in Europe 527

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    Fig. 5. Phylogenetic relationships between Paleogene and extant taxa of the Cypselomorphae (after Mayr, 2001d, 2002g, 2003c,2004d ), with gures of Scaniacypselus szarskii (Peters 1985) (Apodidae, left, specimen SMF-ME 3576a in ForschungsinstitutSenckenberg) and Parapreca kelleri Mayr 1999 (Nyctibiidae, right, specimen SMF-ME 3727a in Forschungsinstitut Senckenberg)from the Middle Eocene of Messel in Germany. Extinct taxa are indicated by a dagger, the arrows indicate the crown-groups. Thenodes are supported by the following diagnostic synapomorphies : 1 skull, palatine bone with strongly protruding anguluscaudolateralis ; processus basipterygoidei reduced; quadratum with pneumatic foramina on caudal surface of processus oticus ;coracoid, extremitas omalis hooked and processus lateralis greatly reduced ; sternum, incisions in caudal margin closed or completelyreduced; musculus splenius capitis with cruciform origin. 2 Proximo-dorsal part of narial openings covered by an osseous sheet ;humerus and ulna strongly abbreviated and hand greatly elongated. 3 Sternum, facies articularis coracoideus weakly saddle-shaped or convex ; humerus, ratio length of bone : width of shaft in midsection less than 7.0. 4 Humerus, tuberculum supra-condylare ventrale elongated and narrow; humerus, processus musculi extensor metacarpi radialis shifted proximally, situatedin proximal two-thirds of the bone ; humerus, ratio length of bone: width of shaft in midsection less than 5.0 ; radius, distal end with

    528 Gerald Mayr

  • from the Quercy ssure llings, is, however, a junior syn-onym of Aegialornis gallicus from the same locality (Mayr,2003a).Recently, stem-group representatives of hummingbirds

    (Trochilidae) have also been identied in the Paleogene ofEurope, which greatly improves our knowledge on the earlyevolution of this fascinating group of birds (Mayr, 2003 c, d,2004d). The rst specimens were described as an extincttaxon, the Jungornithidae, from the Lower Oligocene ofthe Caucasus (Karhu, 1988). In addition to the LowerOligocene JungornisKarhu 1988, Karhu (1999) subsequentlyreported a second jungornithid , Argornis, from the UpperEocene of the Caucasus. Karhu (1988, 1999) noted derivedsimilarities between jungornithids and modern humming-birds which he attributed to convergence, assigning theJungornithidae to swifts. However, analysis of the phylo-genetic relationships between modern and fossil apodiformbirds showed the Jungornithidae sensu Karhu (1999) tobe paraphyletic, with Argornis and Jungornis to be successivesister taxa of modern hummingbirds (Mayr, 2003 c ; Fig. 5).Argornis and Jungornis are known from wings only, but anArgornis-like bird was described from Messel, and in thisspecimen for the rst time the complete skeleton andthe feathering of these birds are preserved (Mayr, 2003a).The Messel taxon, Parargornis Mayr 2003, still had a swift-like beak and an owlet-nightjar-like feathering, broad wingsand a long tail (Mayr & Manegold, 2002; Mayr, 2003a).In the Lower Oligocene, however, even nectarivorous,modern-type hummingbirds occurred in Europe, althoughthese are outside the crown-group of Trochilidae, too(Mayr, 2004d ). Eurotrochilus Mayr 2004 is neverthelessstrikingly similar to modern hummingbirds and leavesno doubt that early hummingbird evolution was not re-stricted to the New World, with all its implications for theevolution of the ornithophilous Old World ora (see Mayr,2004d ).

    Cypselavus gallicus Gaillard 1908 from the Upper Eoceneand Lower Oligocene of the Quercy is generally assignedto the Hemiprocnidae (tree swifts, e.g. Harrison, 1984a ;Peters, 1985; Mourer-Chauvire, 1988b). However, thecoracoid that was assigned to C. gallicus by Mourer-Chauvire(1978) was described as a new taxon of the Jungornithidae,by Karhu (1988), and its humerus also resembles thecorresponding bone of the contemporaneous Argornis withwhich it has not yet been compared (Mayr, 2003a).

    ( r ) Trogoniformes (trogons)

    Trogoniformes are well characterized by the unique hetero-dactyl foot in which the second toe permanently directsbackwards. Their earliest fossil records, not only fromEurope but in general, are an isolated cranium from the FurFormation (Kristoersen, 2002a) and a tarsometatarsusfrom the London Clay (Mayr, 1999a). The latter specimenclearly shows the tarsometatarsal morphology that ischaracteristic for the heterodactyl foot. A complete skeletonof an as yet undescribed trogon has also been identiedin Messel (Mayr, 2005a). Articulated skeletons of LowerOligocene trogons were described from Matt in Switzerland(Olson, 1976) and Cereste in France (Mayr, 1999a, 2001 c).The Cereste trogon, Primotrogon wintersteini Mayr 1999(Fig. 6), is shown to be outside crown-group Trogoniformesby its plesiomorphic skull morphology and the absence ofderived characters of the coracoid (see Mayr, 1999a).

    ( s ) Coraciiformes, Upupiformes, Alcediniformes (rollers, hoopoes,kingshers, and allies)

    The Coraciiformes include the Old World Coraciidae(rollers) and the Madagascan Brachypteraciidae (groundrollers) (Mayr, 1998b). The most basal representatives ofthis taxon are the Primobucconidae, which were originallydescribed from the Lower Eocene of North America butare meanwhile also known from early Eocene deposits ofFrance, Germany, and England (Mayr, Mourer-Chauvire &Weidig, 2004; M. Daniels, personal communication). Stem-group rollers closely resembling the modern taxa were re-ported from Messel (Eocoraciidae) and the Upper EoceneQuercy ssure llings (Geranopteridae) (Mayr & Mourer-Chauvire, 2000). Primobucconidae, Eocoraciidae, andGeranopteridae are successive sister taxa of modern rollers(Mayr & Mourer-Chauvire, 2000; Mayr et al., 2004; Fig. 7).As evidenced by stomach content in someMessel specimens,Paleogene stem-group rollers apparently had a more frugi-vorous diet than their modern relatives (Mayr et al., 2004).Cryptornis antiquus (Gervais, 184852) from the Upper Eoceneof France was assigned to the Bucerotidae (hornbills) byMilne-Edwards (186771), but later transferred to theCoraciidae by Harrison (1979b). It seems to be closelyrelated to, or even conspecic with, Geranopterus alatusMilne-Edwards 1892, although the single known specimen is

    marked tubercle on ventral side of shaft, opposite to tuberculum carpale of ulna ; phalanx proximalis digiti majoris, distal part ofcaudal margin with sulcus for tendon of musculus interosseus ventralis ; tarsometatarsus, deep sulcus on dorsal surface, proximal toforamen vasculare distale ; outermost primaries greatly elongated, measuring at least 2.5 times the length of the longest secondaries.5 Humerus, intumescentia humeri strongly raised with abrupt and steeply sloping dorsal margin ; carpometacarpus greatly elon-gated, about 1.5 times longer than coracoid. 6 Ulna, cotyla ventralis with weakly pronounced ventro-proximal edge ; ulna,olecranon elongated and narrow. 7 Beak greatly elongated (unknown for Jungornis and Argornis) ; humerus, caput humeri bearinga distinct distal protrusion. 8 Ulna strongly abbreviated, with ratio humerus : ulna greater than 0.7. 9 Skull, cone-like bonyprotrusion at caudal margin of foramen nervi optici ; ossa palatina extremely widened; processus paroccipitales strongly protrudingventrally ; mandible with intraramal joint and caudal half of rami mandibulae greatly widened and dorso-ventrally attened; caudalend of mandible unusually small, with very short cotyla lateralis and stout processus medialis ; ossied cartilago tibialis at intertarsaljoint. 10 Jugal bones markedly bowed; tibiotarsus without ossied pons supratendineus ; tarsometatarsus extremely abbreviated.

    The Paleogene fossil record of birds in Europe 529

  • too poorly preserved for a denitive assignment (Mayr &Mourer-Chauvire, 2000).The earliest representative of the Alcediniformes

    (motmots, todies, bee-eaters, and kingshers) is Quasi-syndactylus Mayr 1998 from Messel, which is the sister-groupof the four modern alcediniform taxa (Mayr, 1998b, 2004 c ;Fig. 7). There is no published Paleogene record of Mero-pidae (bee-eaters) and Alcedinidae (kingshers) but rep-resentatives of the New World Momotoidea, i.e. a cladeincluding Momotidae (motmots) and Todidae (todies), werereported from the European Paleogene. Protornis Meyer1844 from the Lower Oligocene of Matt in Switzerland wasassigned to the Momotidae by Olson (1976). Cracraft (1980,p. 13) correctly noted, however, that an alternativehypothesis to be considered is a sister-group relationshipbetween Protornis on the one hand and Todidae+Momoti-dae on the other because it has not been shown thatProtornis shares one or more derived characters with theMomotidae. Todidae were described from the UpperEocene of the Quercy ssure llings, in the taxon PalaeotodusOlson 1976 (Mourer-Chauvire, 1985), originally describedfrom the Lower Oligocene of North America (Olson, 1976).

    Apart from a very similar overall morphology, Palaeotodusescampsiensis Mourer-Chauvire 1985 shares with modernTodidae a derived, greatly elongated tarsometatarsus.However, identication of this species, as well as its assign-ment to Palaeotodus, also needs to be further supported withmore material.Fairly abundant small arboreal birds in Messel are the

    upupiform Messelirrisoridae, which are the sister taxon ofmodern Upupidae (hoopoes) and Phoeniculidae (wood-hoopoes) (Mayr, 1998b, 2000h ; Fig. 7). Messelirrisoridswere also reported from the London Clay and the Geiseltalin Germany (Mayr, 1998b). Another upupiform taxonare the Laurillardiidae that are known from the UpperEocene of France (Mayr, 1998b). Whether Laurillardiidaeand Messelirrisoridae are synonymous (Mlkovsky` 2002,p. 75, contra Mayr, 1998b) or whether the Laurillardiidae,which are about 14 million years younger than theMesselirrisoridae, are more closely related to crown-groupUpupiformes needs to be evaluated by better preservedspecimens of the Laurillardiidae.

    ( t ) Piciformes ( jacamars, pubirds, woodpeckers, and allies)

    The modern European Piciformes belong to the Pici(woodpeckers and allies), which have a very scanty Paleo-gene record, the earliest not only from Europe but ingeneral being a very fragmentary but diagnostic tarso-metatarsus from the Lowermost Oligocene of Belgium(Mayr & Smith, 2001). A more completely preserved tarso-metatarsus was further reported from the Upper Oligoceneof Germany (Mayr, 2001 f ).The tiny, facultatively zygodactyl Middle Eocene to

    Lower Oligocene Sylphornithidae (Mourer-Chauvire,1988a ; Mayr & Smith, 2002b) were recently shown to bestem-group piciform birds (Mayr, 2004 f ). Sylphornithidsprovide a morphological link between the Pici and theirsister taxon ( Johansson & Ericson, 2003; Mayr et al., 2003),the New World Galbulae ( jacamars and pubirds), andcombine a derived, Pici-like carpometacarpus with a plesio-morphic Galbulae-like tarsometatarsus (Mourer-Chauvire,1988a ; Mayr, 2004 f ). As noted by Mayr (1998b), Palaegi-thalus cuvieri (Gervais, 184852) from the Upper Eocene ofFrance may also be a member of the Sylphornithidae.Identication of the Sylphornithidae in Messel (Peters, 1991)turned out to be incorrect, and the specimens belong tothe upupiform Messelirrisoridae.The tiny, long-legged Gracilitarsidae are known from

    three skeletons of Gracilitarsus Mayr 1998 from Messel(Mayr, 1998b, 2001b, 2005 c ; Fig. 7) and were recently alsotentatively identied as stem-group Piciformes (Mayr,2005 c ; Fig. 7). Gracilitarsids were also present in thePaleocene of Brazil (Eutreptodacytlus Baird & Vickers-Rich1997) and the Lower Eocene of North America (Neanisschucherti Feduccia 1973) (Mayr, 2005 c) and, in concordancewith an intercontinental distribution in the Paleogene, theirswallow-like wing bone proportions indicate good ightcapabilities. Gracilitarsidae and modern Piciformes exhibita distinct, derived notch on the medial side of the sternalend of the coracoid that was shown to be a synapomorphy ofPiciformes (Mayr et al., 2003).

    Fig. 6. Primotrogon wintersteini Mayr 1999 (Trogoniformes,specimen SMF Av 432 in Forschungsinstitut Senckenberg)from the Lower Oligocene of Cereste in France.

    530 Gerald Mayr

  • (u ) Primoscenidae ( primoscenids) and Passeriformes ( passerinesor songbirds)

    The zygodactyl Primoscenidae are fairly abundant in theLower Eocene of the Fur Formation, the London Clay,Messel, and the North American Green River Formation(Mayr, 1998b ; Kristoersen, 2002b). The phylogeneticanities of these birds are uncertain, and they were con-sidered to be most closely related to either Piciformes(Mayr, 1998b) or Passeriformes (Harrison & Walker, 1977;Harrison, 1982b ; Mayr, 2004 f ). Primoscenids unquestion-ably are closely related to the Lower Miocene Zygodac-tylidae (Ballmann, 1969; Mayr, 1998b), but whetherprimoscenids and zygodactylids are sister taxa (Mayr,2004 f ) or whether primoscenids are the sister-group of thetaxon (Zygodactylidae+Pici) (Mayr, 1998b) is uncertain(Mayr, 2004 f ).The earliest fossil record of a passeriform bird comes from

    the Eocene of Australia (Boles, 1995, 1997), although thedescribed specimens are fragmentary (proximal carpometa-carpus and distal tibiotarsus) and need to be substantiated byfurther remains. There are no Paleogene passerines fromAfrica and the New World. Passeriformes were not foundin Eocene European deposits that yielded numerous smallbirds, and their earliest European fossil records are from theLower Oligocene of France (Roux, 2002) and Germany(Mayr & Manegold, 2004). These fossils have not beenassigned to any modern passeriform group and at least thespecimen from Germany may be outside crown-groupPasseriformes (Mayr & Manegold, 2004). However, theearliest European Passeriformes already closely resembletheir modern counterparts (Mayr & Manegold, 2004),which supports the hypothesis that evolution of Passeri-formes took place outside the Northern Hemisphere (e.g.Olson, 1989; Ericson, Irestedt & Johansson, 2003).Few remains of passeriform birds were further described

    from the Upper Oligocene of France (Mourer-Chauvire,Hugueney & Jonet, 1989) and Germany (G. Mayr, unpub-lished data). The French specimens were assigned toOscines, the subclade of Passeriformes to which all modernEuropean species belong (Mourer-Chauvire et al., 1989).Most notably, however, even in Miocene deposits ofGermany and France there are still fossil passerines thatappear to be outside crown-group Eupasseres, i.e. the cladeincluding Suboscines and Oscines (Manegold, Mayr &Mourer-Chauvire, 2004).

    III. BIOGEOGRAPHIC AFFINITIES OF

    PALEOGENE EUROPEAN BIRDS

    As recognized by earlier authors (e.g. Houde & Olson,1989; Peters, 1991; Blondel & Mourer-Chauvire, 1998), theLower Eocene avifaunas of Europe and North Americaare very similar, owing to the intermittent presence of landconnections by that time (Smith, Smith & Funnell, 1994).Unfortunately, it is not possible to draw generalizing con-clusions on the biogeography of birds in the Paleogene,as very little is yet known on Paleogene avifaunas of Asia(e.g. Kurochkin, 1976; Nessov, 1992), and the Southern

    continents (e.g. Tonni, 1980; Rasmussen et al., 1987;Vickers-Rich, 1991).Some Eocene birds are stem-group representatives of

    avian groups with a worldwide distribution, but the crown-group members of several other taxa have a very dierentdistribution than their stem-lineage representatives thatoccur in the Paleogene of Europe (e.g. Mourer-Chauvire,1982, 1999; Olson, 1989; Peters, 1991).

    (1 ) Australia

    Australia was widely separated from Asia until the earlyNeogene (e.g. Smith et al., 1994), and Paleogene Europeanbirds do not show close anities to the modern Australianavifauna. Podargidae today only occur in the Australasianregion, and their presence in the Paleogene of Europeshows that they reached Australia via Asia as assumed byearlier authors (e.g. E. Mayr, 1972). If the occurrence ofAnseranatidae in the Paleogene of Europe (Olson, 1999b ;Mourer-Chauvire et al., 2004) can be further supported,magpie geese may be another group of birds that colonizedAustralia from the North.The earlier recognition of Megapodiidae in the Eocene

    of France (Mourer-Chauvire, 1982) was based onplesiomorphic overall resemblance and these birds, theQuercymegapodiidae, are now considered stem-group rep-resentatives of Galliformes (Mourer-Chauvire, 1992a andabove). The fossil record thus does not support the as-sumption that megapodes, the earliest fossil record of whichis from the late Oligocene of Australia (Boles & Ivison,1999), reached Australia via Asia (contra Olson, 1980, 1989;Mourer-Chauvire, 1982), although this may be true forstem-group Galliformes. Because the Quercymegapodiidaeare outside crown-group Galliformes, they provide noevidence that the distribution of extant Megapodiidae isrelictual (contra Mourer-Chauvire, 1992a, p. 90).As also noted above, the alleged record of Aegothelidae

    in the Quercy deposits (Mourer-Chauvire, 1982) needs tobe conrmed by more skeletal elements.

    (2 ) Africa

    The closest extant relatives of comparatively few PaleogeneEuropean avian taxa are restricted in their distribution tocontinental Africa, i.e. the six modern coliiform species,Musophagidae, and the single extant species of the Sagit-tariidae. If correctly assigned to the Leptosomidae, theclosest modern relatives of Plesiocathartes live on Madagascar.Musophagidae are also known from the Lower Oligocene

    of Egypt (Rasmussen et al., 1987) and thus evidently had awider distribution in the past. Turacos are frugivorousbirds with a poor migration ability (Turner, 1997) and theirrelictual present distribution may thus be due to climaticcooling towards the Neogene.

    (3 ) South and Central America

    Most surprisingly given the isolation of South Americaduring most of the Tertiary (Smith et al., 1994), a fairly largenumber of Paleogene European taxa have their closest

    The Paleogene fossil record of birds in Europe 531

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    edin

    idae

    Gal

    bu

    lae

    Pic

    i

    Bra

    chyp

    tera

    ciid

    ae

    Ph

    oen

    icu

    lidae

    Up

    up

    idae

    Bu

    cero

    tid

    ae

    3

    2

    1 4

    5

    6

    7

    8

    9 11

    10

    Upupiformes Coraciiformes Alcediniformes Piciformes

    10 mm

    Fig. 7. Phylogenetic relationships between Paleogene and extant taxa of coraciiform, alcediniform, upupiform, and piciform birds(after Mayr, 2000h, 2002b, 2004 c, f, 2005 c ; Mayr &Mourer-Chauvire, 2000; Mayr et al., 2004), with gures ofMesselirrisor halcyrostrisMayr 1998 (Messelirrisoridae, left, holotype specimen) and Gracilitarsus mirabilis Mayr 1998 (Gracilitarsidae, right, specimenSMNK.PAL.3837 in Staatliches Museum fur Naturkunde, Karlsruhe) from Messel. Extinct taxa are indicated by a dagger, thearrows indicate the crown-groups. The nodes are supported by the following diagnostic synapomorphies : 1 mandible with rec-tangular or trapezoid cross section in proximal area of pars symphysialis and more or less well-developed processus retroarticulares ;coracoid with very wide facies articularis sternalis ; extremitas omalis of furcula widened and with short processus acromialis ;hypotarsus, tendon of musculus exor hallucis longus enclosed in bony canal. 2 Ulna, shaft with projection distal to cotyla dorsalis ;carpometacarpus, osseous ridge from ventral margin of os metacarpale minus to processus pisiformis and caudal margin of osmetacarpale minus undulated. 3 Coracoid, processus lateralis very irregularly shaped and margo medialis with distinct mediallyprotruding projection; phalanx proximalis digiti majoris hooked; sternum, spina externa et interna fused to form a spina communis.4 Carpometacarpus, os metacarpale minus with ventrally protruding projection on ventral side of proximal end; tarsometatarsus,canalis interosseus distalis plantarly not ossied, forming a deep, narrow sulcus on the plantar surface of the bone, between thetrochleae metatarsorum III and IV. 5 Skull, processus postorbitales greatly elongated. 6 Skull, processus postorbitalis withcranially directed projection, carpometacarpus. 7 Carpometacarpus, os metacarpale minus with foramen on ventral side ofproximal end. 8 Hallux, rst phalanx with proximal end greatly widened; second and third toe coalescent for part of their length.9 Columella with large, hollow, bulbous basal and footplate area exhibiting a large fenestra on one side ; scapi claviculae of furculavery narrow at extremitas sternalis ; carpometacarpus with os metacarpale minus distinctly exceeding os metacarpale majus inlength. 10 Coracoid with distinct notch on medial side of extremitas sternalis ; humerus with far ventro-distally extending, large

    532 Gerald Mayr

  • extant relatives in South or Central America (Mourer-Chauvire, 1982, 1999). Examples therefore are the Idior-nithidae, which is the sister taxon of the South AmericanPhorusrhacidae and Cariamidae (e.g. Mourer-Chauvire,1983a ; Mayr, 2002 c), stem-group Nyctibiidae, stem-groupTrochilidae (although crown-group hummingbirds todayoccur in both Americas, they unquestionably originatedin South or Central America, e.g. Bleiweiss, 1998b), andMomotoidea.Cathartidae today occur in the entire New World and

    were reported from the Paleogene of South America(Alvarenga, 1985) ; their extant distribution can thus beconsidered relictual. Whether this is also true for the dis-tributions of the other taxa, or whether these shifted inthe course of time, remains unknown although I consider arelictual distribution to be more likely.Restriction of the crown-group of the above taxa to South

    America is unlikely to be due to climatic cooling in theTertiary alone, as these birds are also absent from thetropical zones of Africa and Asia. Future research will thusalso have to focus on ecological characteristics that dis-tinguish New World biotas, especially in South and CentralAmerica, from those in the Old World. Large herbivores,for example, occur in much lower biomass densities in theNeotropics (Cristoer & Peres, 2003), and in order toexplain absence of hummingbirds in the Old World,Cristoer & Peres (2003, p. 1369) hypothesized that thenectar-rich and highly nutritient understorey owers thatare pollinated by hummingbirds in the Neotropics wouldbe eaten by mammalian herbivores in the Palaeotropics.At present this assumption cannot be tested, as we do notknow when exactly hummingbirds disappeared from theOld World and whether this date coincides with theappearance of large herbivores. However, even if thisparticular hypothesis may turn out to be wrong, it opens aview on complex ecological interactions that may have tobe taken into account to explain the present distributionof birds.

    IV. DIVERSIFICATION TIME OF MODERN

    NEORNITHINE LINEAGES

    Because few neornithine (crown-group) birds are knownfrom the Mesozoic period and virtually all of these comefrom the late Cretaceous (Hope, 2002), the fossil record hasbeen considered indicative of an explosive radiation ofneornithine birds in the Paleogene (Feduccia, 1995, 2003;Blei