Hydrobiologia 515: 75–78, 2004.© 2004 Kluwer Academic Publishers. Printed in the Netherlands.

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A new species of the ‘Copidognathus tricorneatus’ group (Acari:Halacaridae) from India

Tapas Chatterjee1, C. Annapurna2 & Cheon Young Chang3

1Department of Biology, Indian School of Learning, I.S.M. Annexe, P.O. - I.S.M., Dhanbad-826004,Jharkhand, India E-mail: drtapasisl@yahoo.co.in2Department of Zoology, Andhra University, Visakhapatham, Andhra Pradesh, India3Department of Biology College of Natural Sciences, Daegu University, Gyeongsan, 712-714 KoreaE-mail: cychang@daegu.ac.kr

Received 7 May 2003; in revised form 1 September 2003; accepted 2 September 2003

Key words: Copidognathus, marine Halacaridae, Acari, India, new species

Abstract

A new species of the Copidognatus tricorneatus group, C. andhraensis is described on the basis of the specimenscollected among the phytal samples from Visakhapatnam, India (Bay of Bengal). Similarities and dissimilaritieswith the related species are discussed. This is the first record of C. tricorneatus group from India.

Abbreviations: AD, anterior dorsal plate; AE, anterior epimeral plate; ds, dorsal setae of idiosoma; ds1-6, dorsalsetae 1–6; GA, genitoanal plate; GO, genital opening; OC, ocular plate; PAS, parambulacral setae; PD, posterior-dorsal plate; PE, posterior epimeral plate; PGS, perigenital setae; P1–P4, first to fourth palpal segment; SGS,subgenital setae; vs, ventral setae.

Introduction

There are many natural groups present under the genusCopidognathus. One of such group is Copidognathustricorneatus group (Bartsch, 1993, 1997; Otto, 2001) .A new species, Copidognathus andhraensis belongingto this group is described here from Visakhapatnam,Bay of Bengal, east coast of India. Mites were clearedin lactic acid and mounted in glycerine jelly. Type spe-cimens are deposited in the Department of Biology,Daegu University, South Korea.

Description

Family Halacaridae Murray, 1877Subfamily Copidognathinae Bartsch, 1983Copidognathus andhraensis n. sp. (Figs 1, 2)Material examined: Holotype male (DB50017) andone female paratype (DB50018) are deposited in theDepartment of Biology, Daegu University, South

Korea; one male and one female kept in the firstauthor’s (T. Chatterjee) research collection.Etymology: Named after the State Andhra Pradesh (astate in India) where the samples were collected.Male: Body 230–250 µm long dorsally. All dorsalplates separate and with reticulate panels, devoid ofrosette pores (Fig. 1A). AD with two, frontal and me-dial, elevated panelled areas. First dorsal seta, ds1located posterior to the middle elevated area (Fig. 1A,B). A pair of gland pores present on the anteriorside of middle elevated area of AD. Parallel striaefound in the cuticular membrane between AD andPD. OC (Fig. 1C) bearing two corneae anteriorly,with the posterior cornea divided along a slightly ob-lique medial plane; OC acute posteriorly, extendingupto the level of insertion of leg III; ds2 located atanterior side of OC. PD (Fig. 1A, D) long, cover-ing 2/3 of idiosoma; two middle costae becomingthickened posteriorly, and convergent; foveated panelspresent between two costae posteriorly. Anterior partof middle costae forming very faint lines, not extend-

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Figure 1. Copidognathus andhraensis n. sp. (A) Idiosoma, dorsal (male). (B) Posterior areola and ds1 of AD. (C) OC. (D) PD (female). (E)Idiosoma, ventral (male). (F) Magnified view of part of AE. (G) GA of male. (H) Gnathosoma. (I) GA of female. Scales = 50 µm.

ing to the anterior end of PD, and nearly reaching thelevel of ds3; ds3 close to anterolateral margin of PD;ds4 and ds5 situated along lateral margin of middlecostae.

All ventral plates separate (Fig. 1E). Areolationfound on the first coxal prominence of AE. AE(Fig. 1E, F) with 3 pairs of setae and a faint notch lat-eral to insertion of leg I. PE with 3 ventral and 1 dorsalsetae. Porose areola absent on PE. Paragenital areolaegreatly enlarged anteriorly and occupying almost en-tire length of GA, but not touching anterior margin ofGA (Fig. 1E, G). PGS numbered 32–34. Four pairs ofSGS present.

Rostrum extending upto the middle of the palpalpatella (Fig. 1H). Ventrolaterally gnathosoma por-ose. Tritorostral seta long, present near the middleof rostrum. Palp consisting of 4 segments. Palpaltrochanter and patella without any seta. Palpal femurwith 1 anterodorsal seta. Palpal tibiotarsus (P4) with 3long setae basally and 1 short seta distally.

Chaetotaxy of legs: trochanter 1-1-1-0; basifemur2-2-2-2; telofemur 5-5-2-3; patella 4-4-3-3; tibia 7-7-5-5 , tarsus (excluding PAS) 7-4-4-4. Legs long andslender. Telofemur III devoid of ventral seta; telofemurIV with one ventral seta. Tibia I with 4 dorsal, and 3ventral setae; all ventral setae smooth and long. Tibia

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Figure 2. Copidognathus andhraensis n. sp., male. (A) Leg I. (B) Leg II. (C) Leg III. (D) Leg IV. Scale = 50 µm.

II with 4 dorsal and 3 ventral setae (2 ventral setae pec-tinate, and 1 smooth and long). Tibia III with 2 dorsal,2 ventral (1 pectinate and 1 smooth), and 1 ventro-medial smooth setae. Tibia IV with 2 dorsal, 2 ventraland 1 ventromedial setae (all smooth). Tarsus lll with4 dorsal setae, the distance between two basal setaea little more than the height of tarsus. All legs withtwo lateral claws with a tooth dorsally and a bidentatemedian claw. Lateral claw of tarsus I smooth ventrally,lateral claws of tarsi II–IV with pecten ventrally.

Female: Body 235–255 µm length, resembling themale except for genitoanal region. Three pairs of PGS,and one pair of SGS present (Fig. 1I). GO 46 µm long.The distance between anterior margin of GO to that ofGA about 1.1 times of GO’s length. Ovipositor long,surpassing almost equal length of GO, extending uptoalmost 89% of anterior part of GA. Paragenital areolaelarge, running towards the anterior end of GA.

Remarks

Present species belongs to Copidognathus tri-corneatus group. The characteristics and review ofthis group were given in Bartsch (1997). Twelvespecies are so far known under this species group:C. dictyotellus Bartsch from Australia (Bartsch, 1998),C. dictyotus Bartsch from Malaysia (Bartsch, 1993),C. hummelincki (Viets) from the Atlantic and Carib-bean Sea (Viets, 1936; Bartsch, 1997), C. kagamiliNewell from northeastern Pacific and Aleutian Is-lands (Newell, 1950), C. leptoporus Otto and C. me-galoporus Otto from northeastern Australia (Otto,2001), C. longipes Bartsch from northwestern Atlantic(Bartsch, 1973), C. mucronatus Viets from BlackSea (Viets, 1928; Bartsch, 1997), C. quadricostatus(Trouessart) from northeastern Atlantic and Mediter-ranean (Trouessart, 1894; Bartsch, 1997), C. tri-corneatus (Viets) from eastern Australia (Viets, 1938;Bartsch, 1997), C. trouessarti (Voinov) from north-eastern Atlantic and Mediterranean (Voinov, 1896;

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Bartsch, 1997), and C. xaixaiensis Proches fromMozambique (Proches, In press).

Second dorsal seta (ds2) is present inside OC inthe following species: C. dictyotus, C. hummelincki,C. kagamili, C. leptoporus, C. megaloporus, andC. xaixaiensis.

The present species differs from all members oftricorneatus group described so far in the shape ofparagenital areolae.

Copidognathus hummelincki and C. kagamili arecharacterized by the rosette pores on costae, which areabsent here. Tarsi III and IV show 4:4 dorsal setae inC. hummelincki, but 4:3 in C. andhraensis.

Copidognathus kagamili has 6–7 pairs of PGS infemale. Last dorsal seta (ds5) is medial to costae inC. hummelincki, but lateral to costae here.

Costae on PD and posterior areola of AD are por-ose at some regions in C. dictyotus, while porosenature is absent in the present species. The distancebetween anterior end of GO to that of GA is about1.1 times the GO’s length in C. andhraensis, while2.8 times in female of C. dictyotus. Ovipositor abouttwice the length of GO in C. dictyotus, but almostequal the length of GO in C. andhraensis. Female par-agenital areola goes about halfway of GA anteriorlyin C. dictyotus, but almost upto the anterior end ofGA, covering nearly entire length of GA in the presentspecies (Fig. 1I). In C. dictyotus anterior PGS of fe-male is far away from the anterior margin of GA, incontrast to that PGS closer to the anterior margin ofGA in C. andhraensis.

The shape of paragenital areolae of C. andhraensisis different from that of C. leptoporus. Anterior PGSis far from anterior margin of GA in C. leptoporus.The distance between anterior end of GO to that ofGA also differentiates two species each other. Elong-ated is the porose areolae on 1st coxal prominances inC. andhraensis, while small and oval in C. leptoporus.

Copidognathus megaloporus Otto recorded fromAustralia has the pitted posterior areolae on AD, butthis species lacks such pits. The paragenital areolaeare not well developed in C. megaloporus. First coxalprominence does not contain porose areola in C. me-galoporus. Tibia I bears two pectinate setae in C. me-galoporus, while all ventral setae of tibia I are longand smooth in C. andhraensis.

In C. xaixaiensis, paragenital areola is not de-veloped; telofemur IV is devoid of ventral seta; poroseareola is not developed in 1st coxal prominence; setaof patella I is far extending beyond anterior end oftibia I. In contrast, the present species contains well-

developed paragenital areolae; areolae on 1st coxalprominence are well developed; telofemur IV bearsone ventral seta; and patella I does not contain unusu-ally long seta.

Acknowledgements

Thanks are due to Dr Ivano Morselli, Università diModena e Reggio Emilia, Italy; Dr Ilse Bartsch,Forschungsinstitut Senkenberg, Germany, Dr HiroshiAbe, Nihon University, Japan and Dr Marleen DeTroch, University of Ghent, Belgium for their moralsupport. We are grateful to two anonymous reviewersfor their helpful comments that greatly improved themanuscript. This research was partly supported by aDaegu University Research Grant, 2003.

References

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