In spite of several recent studies, confusion still surrounds on the identification of few Indian

clupeoids sucfi as Sardinella, llisha and Thryssa because of their morphological similarity between

species, which has severely restricted the useful biological studies CBabu Rao, 1962; Whitehead, 1973;

Ramaiyan and Whitehead, 1975; and Wongratana, 1983).

Of all the clupeids. the identification of the species of Sardinella by various authors based

on meristic and morphomairic characters is often confusing. The identity of S. longiceps, S clupeoids,

S. leiogaster, S. sirm based on few meristic and morphometric characters is relatively easy however,

the same characters are not satisfactory for S. albelia. S. brachysoma, S. dayi, S. fimbriata, S.

gibbosa, S. melanura and S. sirtdensis

Manickasundaram, M

Ramaiyan, V

Sivakumaran, K V

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CMFRI bulletin 44 Part One JUNE 1989 NATIONAL SYMPOSIUM ON RESEARCH AND DEVELOPMENT IN MARINE FISHERIES MANDAPAM CAMP 16-18 September 1987 Papers Presented Sessions I & II ^xs^e"" %^ CENTRAL MARINE FISHERIES RESEARCH INST ITUTE ( Indian Counci l of Agr icu l tu ra l Research) P. B. No. 2 7 0 4 , E. R. G. Road, C o c h i n - 6 8 2 0 3 1 , India # c a> O 40 YEADS "Oy. P a . i > e v - 2 6 PROBLEMS OF IDENTIFICATION AMONG S P E C I E S O F SARDINELLA K. P. Sivakumaran, M. Manickasundaram and V. Ramaiyan Centre of Advanced Study in Marine Biology, Annamalai University, Parangipettai 608502 ABSTRACT in spite of several recent studies, confusion still surrounds on the identification of few Indian clupeoids sucfi as Sardinella, llisha and Thryssa because of their morphological similarity between species, which has severely restricted the useful biological studies CBabu Rao, 1962; Whitehead, 1973; Ramaiyan and Whitehead, 1975; and Wongratana, 1983). Of all the clupeids. the identification of the species of Sardir>ella by various authors based on meristic and morphomairic characters is often confusing. The identity of S. longiceps, S clupeoids, S. leiogaster, S. sirm based on few meristic and morphometric characters is relatively easy however, the same characters are not satisfactory for S. albelia. S. brachysoma, S. dayi, S. fimbriata, S. gibbosa, S. melanura and S. sirtdensis. The present atudy demonstrating the unsuitability of meristic and morphometric characters for the idnntiflcation of the species of Sardinella cautions the pcssiblllty of mixed material in future biological investigations on Sardinella. INTRODUCTION Clupeoid fishes particularly sardines, her-rings and shads although comparatively smaller in size, occur in large shoals contributing to important fisheries of the world such as the British herrings, pilchards, Peruvian anchoveta. Pacific sardines and lesser sardines and Indian oil sardine to Indian fisheries. Knowledge on the systematics, fishery and biology of the clupeoid resources is an important prerequisite for their proper understanding and rational exploitation. In India, the clupeoid fishes including the lesser sardines in general and particularly the oi l sardine Sardinella longiceps contribute much to Indian pelagic fisheries. In spite of several recent studies (wongra-tana, 1983; Talwar and Kackar, 1984 and Whitehead, 1985) confusion stil l surrounds on the identif ication of species of Indian clupeoid fishes such as Sardinella llisha and r/iAysfa, because of their morphological simila-rity between species which has severely restricted the useful biological investigations. The identification of the species of Sardinella by various authors, based on many characters is often confl ict ing and totally confusing. Hence, the present paper, whi le demonstrating the unsuitability of the maristic and morphometric characters for the identifica-t ion of S. gibbosa, S fimbriata, S. brachysoma, S. sindensis, S. albelia based on material collected from parangipettai, suggests means to overcome this diff iculty. MATERIAL AND METHODS The material for the present study consisting of specimens of oil sardine {Sardinella longiceps) and lesser sardines (5. dayJ, S^ albelia, S. brachysoma, S. fimbriata, S. sindensis, S gibbosa and S. melanura) were collected from parangipettai fish landing centre. The specimens were obtained thrice a week from the commercial catches operated by gillnets for a period of 5 months from April to August 1986. Only standard morphometric measurements (total length, standard length, head length and body depth) and meristic counts (lower gil l rakers on first arm and abdominal scutes) ware made on all the speci-mens obtained. Tha size range of the specimen varied from 60 mm-135 miV« in S.L. The morphometric measurement were made of the left side of the specimen. BULUTIN 44 223 TABLE - 1. Ranges of morptiometric and meristics of various species of Sardinella as recorded by various autfiors. Name of the species Authors Name Number of Gill rakers on lower limb of first gill arch. Number of belly scutes (1) (2) (3) (4) Depth of body (% of S. L.) (5) 1. Sardinella aibella 2. Sardinella brachy soma 3. Sardinella dayi 4. Sardinella flmbrlata 5. Sardinella gibbosa 6. Sardinella melanura 7. Sardinella sindensis 8. Sardinella jussuie Whitehead and Wongratana (1983) Talwar and Kacher(1984) Whitehead (1985) Present Study Whitehead and Wongratana (1983) Talwar and Kacker (1984) Whitehead (1985) Present study Whitehead and Wongratana (1983) Talwar and Kacker (1984) Whitehead (1986) Present Study Whitehead and Wongratana (1983) Talwar and Kacker (1984) Whitehead (1985) Present Study Whitehead and Wongratana (1983) Talwar and Kacker (1984) Whitehead (1985) Present Study Whitehead and Wongratana (1983) Talwar and Kacker (1884) Whitehead (1985) Present study Whitehead and Wongratana (1983) Talwar and Kacker (1984) Whitehead (1985) Present Study Whitehead and Wongratana (1983) Talwar and Kacker (1984) Whitehead (1985) Present Study 41-68 40-67 41-68 44-61 49-65 48-67 50-65 88-132 80-132 88-126 54-89 38-77 33-77 39-72 88-101 88-126 30-32 31-32 29-33 29-33 29-32 29-32 29-32 31-32 31-32 30-32 29-32 31-34 31-34 31-33 30-34 31-32 25-40 24-39 25-40 25-36 28-40 30-39 30-38 34-38 34-38 25-35 53-82 54-82 56-82 40-68 38-65 45-59 40-64 38-74 33-74 38-74 39-72 29-32 29-33 29-32 32-34 31-35 32-34 31-34 28.30 28-30 28-30 28-30 25-35 25-34 26-34 22-32 22-31 24-30 24-31 30 25-30 27-30 27-30 21-35 21-35 21-23 28-37 28-37 224 CMFBI OBSERVATION AND DISCUSSION The ranges of the morphometric and meristic data of the Sardines studied presently are provided in Table 1 along wi th the ranges observed by earlier authors. The objective of the present study is to highlight the unsuitabi-lity of the morphometric and meristic data alone for the proper identif ication of the species oi Sarcf/nel/a because of their morphological similarity between species. Of the species of Sardinella studied S. longiceps could easily be identified based on its longer head length (29-35% S. L.). Similarly, the jet black caudal f in tips distinguish S. molanura from all other species of Sardinella, however the identity of other species based on morpho-metric and meristic charactors is not always easy. The meristic counts (abdominal scutes and lower gillrakers) of 5 . dayi, overlap with that of jessieui, though reported to occur along western coasts of India from Bombay to Srilanka though not recorded from parangipettai coast. However, Wongratana (1985) has separated the two species based on abdominal scutes, but his range of scute count overlap. Further, there is no siginificant variation either in body depth or in lower gillraker counts between these two species. The abdominal scutes range from 29-34 in the various species of Sardinella (S. albella, 29 33, 5 brachysoma, 29-32, S. f/mbriata' 29-33, S. gibbosa, 31-35 and S. sindensis 31-34) as reported by wongratana (1983). Talwar and Kacker (1984) and Whitehead (1935), however the separation of species based on abdominal scutes is definitely not easy in routine analysis. The variation in the range of lower g i l l -rakers is often employed for the identification of the above mentioned species. The lower gillrakers range from 38-68 in various species of Sardinella excepting S. dayi (80-132) and S. jussieni (88-126), however, the range of lower gillrakers in S. albella (40-68) , S, brachysoma (48-67) S. fimbriata (53-89) , S. gibbosa (33-68) , S. sindensis (38-77) overlap wi th each other indicating their unreliabil ity in separating the species. Depth in percentage of standard length has often been employed for separating the species which is not always easy. Perhaps it could be successfully used to separate the species if the non-overlapping nature is established employing ontogenetic series of specimens as suggested by Whitehead (1985). The nature of the pattern of the striae on scales has been attempted by earlier authors (Whitehead, 1985) to separate the morphologi-cally similar species of Sardinella, however, due to lack of consistency in the pattern, this too can not be successfully employed for the separation of species. As far as the vertical striae on scales are concerned S. brachysoma is distinct in which the striae are continuous at the centre whsreas in S. albslla, S. fimbriata S. gibbosa and S. sindensis the striae pattern is almost exactly similar. Because of the overlapping nature of the morphometric and meristic characters of sardines between species it is suggested that future investigations on the biology of any particula'' species of sardine should be carefully planned because of the possibil i ty of mixed material. Thus the problem of identification of morpholo-gically similar species such as sardines is very acute and this may perhaps be solved to some extend either by employing ontogenetic series of specimens of the species concerned as suggested by Whitehead (Per c o m ) or by developing suitable methods to rear the marine fish larvae as suggested by Kuronuma and Fukuso (1987). ACKNOWLEDGEMENT The authors wish to thank Prof. V. K. Venu-gopalan. Director, C A S in Marine Biology, for providing the facilit ies. The first and second authors are grateful to the UGC for f inancial assistance. REFERENCES M. BABU RAO 1962. Studies on the clupeoid fishes of the Godaran Estuary. Ph. D. Thesis, Andra University. 223 p. BULLETIN 44 225 K. KURONUMA and K. Fukusho 1 987. Rearing of Marine Fish larvae in Japan. Ottawa, Ont., IDRC, 109 p. V, RAMAIYAN AND P. J. P. WHITEHEAD 1975. Notes on Indian species of llisha (Pisces; Clupeidae) J. mar. biol. Assoc. India, 17, ( I ) : 187-198. P. K. TALWAR AND R. K. KACKER 1984. Commercial sea Fishes of India, Publ. by Zoological Survey of India. Calcutta 997 p. P. J. P. WHITEHEAD 1973. A synopsis of the clupeoid fishes of India. J. mar. biol. Assoc. India, 14 (1) 1-68. 160-256, figs. P. J. P. WHITEHEAD AND T. WONGRATANA 1984. FAO species Identification sheets for Area 51, Western Indian Ocean, 5 vols. P. J . P. WHITEHEAD 1985. FAO Fisheries synspsis. Clupeoid Fishes of the world FAO, Rome. Vol. 7. T. WONGRATANA 1983. Diagnosis of 24 New species and proposal of a new name for a species of IndoPacific clupeoid fishes. Jap. Jour, of Ichthy. Vol. 29. No. 4, 385-407, Figs. 1-25. 

Problems of identification among species of sardinella

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Problems of identification among species of sardinella

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