SARDINESBy:

Christian Jay Rayon NobBS-Marine Biology

Mindanao Sate University-Naawan Campus

HISTORY OF THE SYSTEMATICS OF SARDINES

• Fishes in the Order Clupeiformes are teleosts which arose during the early Mesozoic era, approximately 200 million years ago.

• Among these fishes are Sardines. In India, these fishes have been studied for over half a century.

• Since 1947, have been the subject of intensive research by the Central Marine Fisheries Research Institute which was initiated by Dr.Radhakrishnan V. Nair.

95-million year-old fossilized sardine found in Nammoura, Lebanon

Living Specimen

The term “Sardine” was first used in English during the early 15th century and thought to have been named after the Mediterranean Island of Sardinia around which sardines were once abundant.

School of Sardines

• During the World Scientific Meeting on the Biology of Sardines and related species which took place in 1959 in Rome, Dr.Postel and Dr. Den-Tuvia brought to light all the scientific knowledge on sardines and related species hitherto known.

• Sardines are small, silvery, elongated fishes with a single short dorsal fin, and no scales on the head.

• They range in length from about 15 to 30 cm (6 to 12 in) and live in dense schools, migrating along the coast and feeding on plankton.

• They spawn mainly in spring, with eggs and, a few days later, the larvae drifting passively until they metamorphose into free-swimming fish.

Sardines in large schools migrating along the coast

• The term “Sardine” however, is not precise, and what is meant depends on the region. – For example, the United Kingdom’s Sea Fish Authority classifies

Sardines as “young pilchards”. One criterion suggests fish shorter than 6 inches (15 cm) are Sardines, and larger one as Pilchards.

• Sardines are commonly consumed by humans. – grilled, pickled, or smoked, or they are preserved in cans.

• They are rich in vitamins and minerals. – natural source of marine omega 3-fatty acids

• reduce the occurrence of cardiovascular disease. • reduce the likelihood of developing Alzheimer’s disease.

• Since they are low in the food chain, sardines are very low in contaminants, such as Mercury.

• Sardine oil has many uses– manufacture of paint, varnish, and linoleum.

Sardine Products

• Even to the economic importance of sardines, its relationship among and within the main lineages of the Clupeiodei have been explored in few morphological studies and still remain poorly understood.

• Only in the past years, molecular systematic approaches provided new insights into the systematic problems of these clupeids.

• DNA-based identification methods offer an analytically powerful addition or even an alternative in fish-species recognition.

BIODIVERSITY

• Generally, Sardines are classified into 5 Genera:

Genus Dussumeria Genus Escualosa Genus Sardina Genus Sardinella Genus Sardinops

PHILIPPINES Sardinella lemuru (Bali sardinella)

Sardinella gibbosa (Goldstripe sardinella)

Sardinella fimbriata (Fringescale sardinella)

Sardinella albella (White sardinella)

Sardinella hualiensis (Taiwan sardinella)

Sardinella tawilis (Freshwater sardinella)

Amblygaster sirm (Spottedsardinella)

Escualosa thoracata (White sardine)

Herklotsichthys dispilonotus(Blacksaddle herring)

Herklotsichthys quadrimaculatus (Bluestripe herring)

Dussumeria acuta (Rainbow sardine)

• Fishery, species diversity, and resource characteristics of exploited sardine resources of the genera Sardinella were studied during 2000-2008. Annual average production for the period was 20, 249 tons. – Fishery was supported by eight species dominated by

Sardinella gibbosa, followed by S. sirm, S. albella, and S.longiceps.

• Oil sardine in the fishery registered an increasing trend with wide annual fluctuation during the period. – BUT stock assessment studies indicated that sardine

resource as a whole is under-exploited, offering considerable scope for enhancing their yield.

• Ecological role– sustaining the stock and fishery of other predatory

groups by providing them a major share of their forage.

– they support 466 to 87% of the total food of pelagic predators and 14 to 29% of demersal predators

Global capture of sardines in tonnes

Sardines of the Sardinops genus Sardines not of the Sardinops genus

•The fishes are caught mainly at night, when they approach the surface to feed on plankton.

•Typically, sardines are caught with encircling nets,particularly purse seines.

French sardine seiner

TERMS IN THE SYSTEMATICS

• Abdominal: referring to the ventral portion of the body from the thorax to the anal opening and known as the belly; also referring to pelvic fin placement

• Anal fin: the vertical fin on the lower or ventral side of fishes just anterior to the tail and behind the anus

• Anterior: referring to the front portion of the body, fins, or other body part, often used with other directional terms

• Anus: an opening on the ventral surface of the body usually located just anterior to the anal fin (some exceptions) and marking the end of the intestinal tract

• Axil: the armpit or backside of the pectoral fin base

• Axillary (Accessory) scale: a modified, usually elongated scale attached to the upper or anterior base of the pectoral or pelvic fins in certain herring‐like fishes

Branchiostegal membrane: a membrane or membranes situated on the ventral edges of the gill covers and containing the elongated branchiostegal rays

Branchiostegal rays: elongated bones arranged fanwise within the branchiostegal membranes

Caudal fin: referring to the tail fin or the fin on the posterior most part of the body

Cheek: referring to the side of the head just below the eye and extending slightly posteriorly

Compressed: Flattened laterally or squeezed together from the sides

Dorsal: the back or upper part of the body; often used with other directional terms

Dorsal fins: the fins of the midline of the back; usually two, a spiny‐rayed dorsal followed by a softrayed dorsal which may or may not be connected

• Gill: a respiratory organ in fish consisting chiefly of filamentous outgrowths for breathing oxygen contained in water

• Gill arch: the branchial skeleton which contains the gill rakers and the gill lamellae

• Gill raker: the blunt knob like projections on the anterior edge of the first ‐gill arch

• Isthmus: the narrow portion of the breast lying between the gill chambers and separating them

• Midlateral: middle on sides of body, usually where the lateral line is found

• Opercle or Operculum: the large, very flat and thin bones on each side of the head of fishes which cover the gills, also called gill cover

• Pectoral fins: paired fins attached to the shoulder on the side of the body

• Pelvic fins: paired fins on the ventral side of the body, sometimes called ventral fins; they may be posterior to the pectorals (abdominal), below the pectorals (thoracic) or before the pectorals (jugular)

• Premaxillaor Premaxillary: the anterior most bone of each upper jaw forming part or all of the border of the jaw and may bear teeth

• Ray: all the soft and hard rays of the fins, as well as all spines; a soft ray is usually flexible, branched, bilaterally paired and segmented; it may be either a principal or a rudimentary ray; a hard ray is a hardened soft ray that may be a simple spine ray or the consolidated product of branching ‐as in the catfishes; a true spine ray is an unpaired structure without segmentation, usually stiff, and sharpened apically

• Scute: a modified scale, often spiny or keeled; scutes are found along the ventral midline of some species and along the lateral line of others

• Spine: an unbranched, unsegmented hardened ray

• Striae: a wrinkle or stretch like mark or groove‐

• Stripe: a band of contrasting color extending across the outer surface

• Supramaxilla: a wedge shaped, small movable ‐bone attached to the upper edge of the maxilla near its posterior tip

EVOLUTIONARY TREES AND ROOTS

CHARACTERS

• Fish species identification is traditionally based on external morphological features– body shape– pattern of colors– scale size and count– number and relative position of fins– number and type of fin rays– various relative measurements of the body parts– gill rakers are sometimes counted to differentiate

very similar species

Sardinella lemuru

Common Name: Bali sardinellaLocal Name: Tamban/TunsoyDorsal spines (total): 0Dorsal soft rays (total): 13-21Anal spines: 0Anal soft rays: 12 - 23.A faint golden spot behind gill opening, followed by a faint golden mid-lateral line; a distinct black spot at hind border of gill cover (absence of pigment).Body elongate, sub-cylindrical.

Sardinella gibbosa

Common Name: GoldstripesardinellaLocal name: Tamban/TunsoyHave a relatively slender body, and a below average number of gill rakers. They have unique, small perforations on the hind part of their scales along with a dark spot on the dorsal fin. The distribution of S. gibbosa includes the Indo-West Pacific, East African coast, and a range from Madagascar to Indonesia. S. gibbosa are one of most abundant Sardinella in Indo West Pacific, and off the coast of Taiwan, Korea and Australia. Fisheries are most prominent in southern parts of India, with markets throughout Southeast Asia.

Sardinella albella

Common Name: White sardinellaLocal Name: Tamban/TunsoyDorsal spines (total): 0Dorsal soft rays (total): 13-21Anal spines: 0Anal soft rays: 12 - 23.Body somewhat compressed but variable, from slender to moderately deep; total number of scutes 29 to 33. Vertical striae on scales not meeting at center, hind part of scales with a few perforations and somewhat produced posteriorly. A dark spot at dorsal fin origin.Lower gill rakers 41 to 68 (at 4 to 15 cm standard length, increasing a little with size of fish).

Sardinella hualiensis

Common Name: Taiwan sardinellaLocal Name: Tamban/TunsoyDorsal spines (total): 0Dorsal soft rays (total): 13-21Anal spines: 0Anal soft rays: 12 - 23Total scutes 30 to 32. Vertical striae of scales overlapping or sometimes continuous at center of scale, numerous small perforations on hind part of scale. Tips of caudal fin lobes black. From other deep-bodied species in the area which have overlapping or continuous scale striae it differs in having a dark spot at dorsal fin origin.

Sardinella tawilis

Common Name: Freshwater sardinellaLocal Name: TawilisAre small fish reaching up to 15 cm and weighing less than 30 g. Like other members of their family, they have laterally compressed bodies with bellies covered in tough scale-like scutes. They have a single, triangular dorsal fin and a forked caudal fin. They possess long, slender gill rakers in their mouths.

Sardinella fimbriataCommon Name: Fringescalesardinella Local Name: Tamban/tunsoy

Body somewhat compressed but variable, from slender to moderately deep, depth 25 to 34% of standard length; total number of scutes 29 to 33. Two supramaxillae present; second symmetrical, paddle-shaped. Lower gill rakers on first gill arch 54 to 82. Vertical striae on scales not meeting at center, hind part of scales with a few perforations and (in Indian Ocean specimens) somewhat produced posteriorly. Lateral-line scales 42 to 44. Body back blue-green, flanks silvery; a dark spot at dorsal fin origin; tips of caudal and dorsal fins blackish

Amblygaster sirm Common Name: Spotted sardinellaLocal Name: Tamban/TurayDorsal spines (total): 0Dorsal soft rays (total): 13-21Anal spines: 0Anal soft rays: 12 - 23.

Scutes not prominent. Distinguished from A. clupeoides and A. leiogaster by the presence of a series of 10 to 20 gold (in life) or black (on preservation) spots down the flank (but sometimes missing) and more lower gill rakers; from Sardinops species by the absence of a bony radiating striae on its operculum; from Sardinella species by its fewer pelvic fin rays and lower gill rakers.

Escualosa thoracataCommon Name: White sardineLocal Name: BolinawForms schools in shallow waters, the juveniles apparently entering the lower parts of rivers, but returning later to the sea. Feeds on both zooplankton (copepods, crab zoea, larvae of bivalves and fish eggs) and phytoplankton. Breeds from October to February (mainly November to January) off western coast of India, usually in relatively shallow inshore waters.Upper jaw rounded when viewed from front; belly deep, strongly keeled; silver stripe on side, hind margin of tail fin black. Schooling planktivore in coastal areas including estuaries. To 10 cm.

Herklotsichthys quadrimaculatusCommon Name: Bluestripe herringLocal Name: DilatDorsal spines (total): 0Dorsal soft rays (total): 13-21Anal spines: 0Anal soft rays: 12 - 23. Elongate wing-like scales underneath paired pre-dorsal scales. Adults form schools near mangroves, shallow coastal bays and lagoons during the day and moves further offshore into deeper water by night. Known in mills around in large schools under wharves or along sandy beaches in protected bays.Are pelagic. Feeding occurs mainly at night on zooplankton, chiefly copepods by juveniles, and as adults, on larger prey organisms (chaetognaths, polychaetes, shrimps and small fishes). Breeding occurs on the first year and probably survive only a few months after maturity. Do not recover quite as quickly as other species of baitfish after heavy fishing.

Dussumieria acuta

Common Name: Rainbow sardineLocal Name: Tulis/AlabaybayDorsal spines (total): 0Anal spines: 0Anal soft rays: 14 - 18Branchiostegal rays fewer (12 to 15) and posterior part of scales marked with numerous tiny radiating striae. Color is iridescent blue with a shiny gold or brass line below (quickly fading after death); hind margin of tail broadly dark. W-shaped pelvic scute; isthmus tapering evenly forward; more anal fin rays.

EVALUATION OF TREES

• In the middle of the Devonian period, bony fishes had already radiated extensively in the adaption that fitted them for every aquatic habitat.

• Four subsequent radiations gave rise to the current major groups of fishes, with one of these radiations producing the Clupeomorpha to which the sardines belong.

• Furthermore, fish can be divided into fatty and lean species, but this type of classification is based on biological and technological characteristics.

Scientific groupingBiological

characteristics

Technological

characteristicsExamples

Cyclostomes jawless fish lampreys, slime-eels

Chondrichthyes cartilaginous fishhigh urea content in

musclesharks, skate, rays

Teleostei or bony fish pelagic fishfatty fish (store lipids in

body tissue)

herring, mackerel,

sardine, tuna, sprat

demersal fish lean (white) fish (store

lipids in liver only)

cod, haddock, hake

grouper, seabass

KEYS TO GENERA• 1 a. Operculum smooth

2 a. Gill opening with two fleshy outgrowths; pelvic fin rays 8-93 a. Frontoparietalstriae (on top of head) few (3-6) ;

lowerportion of paddle-shaped 2nd supra maxilla longer

than upper

........... Herklotsichthys

3 b. Frontoparietalstriae many (7-14); lower portion of paddle-shaped 2nd supramaxilla equal to upper

........... Sardinella

2 b. Gill opening smoothly rounded; pelvic fin rays 74 a. 2nd supramaxilla large, rectangular; silver stripe on flanks.............. Escualosa

4 b. 2nd supramaxillapaddle-shaped; flanks silvery

............. Sprattus • 1 b. Operculum with radiating bony striae

.............. Sardinops

MOLECULAR SYSTEMATICS

• We live in the age of comparative genomics, and it may seem that there is not much point in reconstructing phylogenies using morphological data anymore.

HISTORICAL CONTEXT

• Dates back to the very origin of the vertebrate lineage and today, half of the last common ancestor between fish and mammals, half of modern of vertebrates, were fishes.

• In the fish population genetics, there is a little information about fish genetic character of fish in natural waters and in the inheritance of those characters. – Need to be developed is the procedures for preservation of natural

gene pool.

BASIC TECHNIQUES• Comparison of homologous sequences for genes

using sequence alignment techniques to identify similarity

• DNA barcoding Mitochondrial DNA Cytochrome b.

• Genome sequence highly informative due to accumulation of neutral

mutations in non-functional region between such distantly related organisms.

IMPACTS ON PHYLOGENETICS

• Analysis of molecular sequences of fishes may provide additional insights into problematical relationships, but are only just beginning to appear.

• Advantages of nucleotide sequence data – Numbers of potential characters available for comparison– rate independence between molecular and morphological evolution– utility of molecular data for modelling patterns of nucleotide

substitution

• There are some molecules appear to be inappropriate for investigating higher level divergences within the fishes , but there are others that are more promising– it must be examined to allow an adequate evaluation of

their utility.

• Congruence of trees generated from independent molecular data set is ultimately required of the convincing support for particular hypothesis of relationship

LIMITATIONS OF MOLECULAR PHYLOGENETICS

• Molecular systematics is an essentially cladistic approach. – all valid taxa must be monophyletic.

• The recent discovery of extensive horizontal gene transfer among organisms provides a significant complication to molecular systematics– indicating that different genes within the same organism can have

different phylogenies.

• Molecular phylogenies are sensitive to the assumptions and models that go into making them. – They face problems like long-branch attraction, saturation,

and taxon sampling problems.

CASE STUDIES

Molecular Phylogeny and Species Identification of Sardines

• The purpose of this work was to study the genetic divergence between Clupeiformes species labeled as sardine type products and to define relevant tools to discriminate these pelagic fishes.

• As most of the external features allowing morphological identification of whole fish are not apparent after processing, there is a need for analytical methods of authentication to detect mislabeling.

• Accordingly, cytochrome b was chosen for its high potentiality to discriminate species and intrafamilial genera.

Multidisciplinary identification of clupeiform fishes from the Southwestern Atlantic Ocean

• In the Southwestern Atlantic Ocean, several described species of Clupeiformes overlap their geographical distribution in the coastal areas from Rio Grande do Sul (Southern Brazil) to Bahía Blanca (Argentina) and the Río de la Plata estuary. – Larvae and juveniles of the SW Atlantic clupeids are very difficult

to discriminate from which genera they belong.

• Implemented phylogenetic analyses based on mitochondrial cytochrome b sequences and morphometric and osteological studies to achieve unambiguous species recognition

• Like the genetic analysis, morphometric approach reveals similar major groups of species

• According to their actual taxonomic status present, morphometric and molecular data resulted in accurate and complementary tools for the individual assignment in clades and groups within SW Atlantic Ocean Clupeiformes

CONCLUSION

• Although the term “Sardine” was first used in 15th century, a 95-million year old fossilized sardine was recovered in Nammoura Lebanon. – With exactly the same skeleton and fins as the living

specimen, it proved that sardines did not change from that time to this.

• It was only in 1947 through the effort of Dr.Radhakrishnan Nair that sardines had been under intensive research by the Central Marine Fisheries Institute. – Since then, world scientific meetings on the biology of

sardines and related species have been held with Dr.Postel and Dr. Den-Tuvia who paved way in publishing knowledge about sardines and their closely related species.

• Traditionally, fishes are identified morphologically.– For instance, their body shape and

measurements, scale size and count, and the number and relative position of their fins.

• But given the incredible rate of advances in molecular systematics, mitochondrial genome sequences have been applied to resolve fish phylogeny and systematics.

Man has to eat, but Fish has to live too!