Short Communication First Record of Seamoths Eurypegasus Draconis
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Iran. J. Ichthyol. (December 2020), 7(4): 356-360 Received: March 16, 2020 © 2020 Iranian Society of Ichthyology Accepted: October 29, 2020 P-ISSN: 2383-1561; E-ISSN: 2383-0964 DOI: 10.22034/iji.v7i4.396 http://www.ijichthyol.org Short Communication First record of Seamoths Eurypegasus draconis (Teleostei: Pegasidae) in the Tamil Nadu coast, India Krishnan SILAMBARASAN1*, Palaniswamy SENTHILKUMAAR2, Arumugam SUNDARAMANICKAM3 1Fishery Survey of India, Beach Road, Visakhapatnam, Andhra Pradesh, India. 2P.G. and Research Department of Zoology, Sir Theagaraya College, Chennai, India. 3Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai, India. *Email: [email protected] Abstract: In the present study a single individual (64 mm SL) of Seamoths Eurypegasus draconis Linnaeus, 1766 was recorded from the Kasimedu fisheries harbour, Chennai coast. This is the first record of the species from mainland of India Chennai, Tamil Nadu coast and third record from Indian waters. After three decades the species were documented in the Indian coast. A systematic account of the species and distributions are provided. The species has been compared with earlier studies and similar species of E. papilio. Keywords: Syngnathiformes, Distribution, Systematics, Indian coast. Citation: Silambarasan, K.; Senthilkumaar, P. & Sundaramanickam, A. 2020. First record of Seamoths Eurypegasus draconis (Teleostei: Pegasidae) in the Tamil Nadu coast, India. Iranian Journal of Ichthyology 7(4): 356-360. Introduction discussed the first report of E. draconis for the Fishes of the family Pegasidae, known as Seamoths mainland India at Chennai coast, Tamil Nadu. and dragonfish, are represented by five species distributed in two genera Pegasus Linnaeus, 1758 Materials and Methods and Eurypegasus Bleeker, 1863. The species are E. draconis P. laternarius Cuvier, 1816; P. volitans Linnaeus, One specimen of was collected from P. lancifer E. draconis trawl catches in the Kasimedu Fisheries Harbour, 1758; Kaup, 1861; Linnaeus, th 1766 and E. papilio Gilbert, 1905 (Nelson 2006). Chennai on 12 , January 2015 (Fig. 1). All They inhabit open sand or muddy substratum in calm morphometrics were measured to the nearest 0.1 mm regions preferably in seagrass beds (Kuiter 1985). using vernier calipers. The specimen was identified The pegasids are distributed in tropical and temperate based on the description given by Munro (1955), waters of Indo-Pacific (Venkateswarlu & Verghese Smith (1986), Palson & Pietsch (1989) and 1980; Palsson & Pietsch 1989) extending from East Peristiwadu (2007). The specimen was preserved in Africa to Japan and Australia (Smith 1965). 5% formalin and deposited in Museum collections of In India, E. draconis was recorded for the first Department of Zoology, Sir Theagaraya College, time in the Andaman Islands by Day (1889). Later, Chennai (Reg. No: ZOMUSP-236). Venkateshwarlu & Verghese (1980) rediscovered in the Lakshadweep Islands. But, no authenticated Results information is available on the Indian mainland. Past Systematics: The present paper follows the decade, Perisitwadu (2007) reported the species for classification provided by Nelson (2006). the Derwan Islands, Indonesia. In this paper, we Division: Teleostei 356 Silambarasan et al. - First record of Seamoths Eurypegasus draconis Tamil Nadu coast, India Fig.2. a (above) dorsal and b (below) ventral view of Eurypegasus draconis. Fig.1. India map showing the sampling site: Kasimedu transparent membranes. Pelvic fins thoracic, Fishing harbour, Chennai, India. tentacle-like, with one spine and two unbranched soft Subdivision: Euteleostei rays. Body finely reticulated with brown. Pectorals Super order: Acanthopterygii with brown dots and white margin. Order: Syngnathiformes Description Family: Pegasidae D 5; A 5; P 10; V I 2; C 8; Vertebrae 20; Tail rings 8. Genus: Eurypegasus Bleeker, 1863 Morphometric data are presented in Table 1. Species: Eurypegasus draconis Linnaeus, 1766 Body short and depressed, completely encased (Figs. 2a, b) infused dermal plates; head triangularly elongate Diagnostic characters: Head and body more or less shape, widest at pectoral bases. Large rostrum angular, depressed, contained in bony plates, tail with extends cover the mouth; mouth very small, inferior. eight rings. Nasal bones elongate, fused, forming a Three pairs of dorso lateral body plates; four pairs of rostrum; mouth inferior and no teeth, jaws and snout ventro-lateral body plates; anal fin inserted on the are protrsible. Gill opening a small hole on dorso- same ring, just opposite to dorsal fin; trough of anal lateral surface behind head. Spinous dorsal fin fin not reaching far back when compared to dorsal absent; soft dorsal and anal fins, each with five rays. fin. Eyes are large. Gill filaments lobe like and with Caudal fin with eight unbranched rays. Pectoral-fins tufts; opercle and sub opercle very small; Preopercle large, wing like structure inserted horizontally very much enlarged. Caudal region composed of composed of ten unbranched spinous soft rays; eight rings. Dorsal fin begins on second caudal ring; pectoral fin rays inter connected with broad, when the fin ad-pressed reaching penultimate. 357 Iran. J. Ichthyol. (December 2020), 7(4): 356-360 PectoralTable 1. fins Morphometric broad wing and like meristic structure; characters rays of gradually Eurypegasus draconisblackish.. Pectoral fin rays brownish; its rays potted Morphometric measurements (mm) Present study Peristiwady (2007) (Indonesia) Standard length 64 4.6 4.65 68.5 Body depth (% SL) 1.8 (28.1) 1.0 1.15 1.80 Body width (% SL) 2.6 (40.6) 1.8 1.95 2.85 Head length (% SL) 1.6 (25.0) 1.7 1.75 2.65 Snout length (% SL) 0.6 (0.93) 0.85 0.90 1.50 Eye diameter (% SL) 0.4 (0.62) 0.4 0.45 0.5 Pre dorsal length (% SL) 3.6 (56.2) 3.35 3.35 4.95 Pre anal length (% SL) 37 (57.8) NA NA NA Anal fin length (% SL) 0.4 (0.62) 0.40 0.45 0.65 Caudal fin length (% SL) 0.8 (1.25) NA NA NA Pectoral fin length (% SL) 0.7 (1.09) NA NA NA Snout to pectoral insertion (% SL) 18 (28.1) 2.25 2.35 3.45 Snout to pelvic insertion (% SL) 25 (39.0) 2.70 2.75 3.85 Snout to anal fin origin (% SL) 31 (48.4) 3.15 3.35 4.90 Weight (gm) 4.8 NA NA NA Meristic characters Dorsal fin rays 5 5 5 5 Anal fin rays 5 5 5 5 Pectoral fin rays 10 11 11 11 Ventral fin rays 2 2 2 2 Caudal fin rays 8 8 8 8 NA: not available elongate postero-medially; outer membranes incised, with incisions gradually shorter backwards; the anterior most ray the shortest. Pelvic fin spine and first ray forming an elongate, tentacular structure. Caudal fin elongated and round shaped composed 8 unbranched rays. Lateral scutes of the trunk and through lateral and ventral scutes of the tail. Eye diameter 0.4 mm in snout length; eye visible in ventral view; ventral ridges of rostrum greatly expanded than dorsal ridges, each with laterally directed denticles; anal papilla absent. Interorbital space transversely concave, two deep grooves on the Fig.3. Distribution map for point data of Eurypegasus draconis. neck. Swim bladder absent; vertebrae amphicoel, anterior six unmovable jointed. Last abdominal and with fine brown dots, membranes of rays clear, first caudal vertebrae with strong ribs, four gills, each pectoral fin with broad milky-white edge connected with a double row of leaves; Pseudobranchiae medially to another whitish band. present. Vertebrae count 19-22, six abdominal Distribution: India: Chennai coast (present report), vertebrae elongated (Figs. 2-3). Andaman Islands (Day 1889), Lakshadweep Islands Colour: Body dark brown colour with reticulations (Venkateshwarlu & Verghese 1980). on dorsal and lateral surfaces; pectoral fins hyaline, Elsewhere: Indian Ocean, Melenesia to the Malay distal margin white and spotted; last caudal ring is Archipelago, East Indies (Day 1889), extending from 358 Silambarasan et al. - First record of Seamoths Eurypegasus draconis Tamil Nadu coast, India East Africa to Japan, Australia and Lord Howe Island the Species. English Edition. Tokai University Press. (Nakabo 2002) and Derwan Islands, Indonesia 186 p. (Peristiwadu 2007) (Fig. 3). Nelson, J.S. 2006. Fishes of the World. 4th Edition. John Wiley and Sons, Hoboken 601. p. Discussion Palsson, W.A. & Pietsch, T.W. 1989. Revision of the acanthopterygian fish family Pegasidae (Order: The morphometric and meristic characters of the Gasterosteiformes). Indo-Pacific Fishes 18: 1-38. species collected were compared with previously Peristiwady, T. 2007. Eurypegasus Draconis Linnaeus, recorded specimens (Table 1) and the diagnostic 1766 (Gasterosteiformes: Pegasidae); A new record characters of the present specimens collected were to the Derawan Islands, Indonesia. Marine Research agreed well with the description of previously in Indonesia 32(1): 35-39. recorded specimens (Peristiwadu 2007). The species Smith, J.L.B. 1965. The Sea Fishes of Southern Africa: E. draconis looks similar to E. papilo (Gilbert 1905) Central News Agency South Africa. 580 p. but some differential meristic characters like head Smith, M.M. 1986. Pegasidae. In: Smith, M.M. & large, blunt snout and long dorsal fins of first rays and Heemstra, P.C. (eds.), Smith’s Sea Fishes. Springer- pectoral fins little large. Moreover, dorsal soft rays 5; Verlag, Berlin 444 pp. anal soft rays 5 and tail rings also 8. Based on the Venkateswarlu, T. & Verghese, G. 1980. Occurrence of the Bat-fish, Pegausu draconis L. (Pegasiformes: above characters the present species is confirmed as Pegasidae) in Lakshadweep (India). Acta E. draconis. Another important aspect of work is the Ichthyologica et Piscatoria 10(1): 55-58. species now re-discovered after 38 years from Indian waters. Conclusion This is the first conformational record of E. draconis at Tamil Nadu coast. Acknowledgements The authors are grateful to Dr. Annada Bhusan Kar, Fisheries Scientist, Fishery Survey of India, Visakhapatnam, Andhra Pradesh, India, for providing the species distribution map and offering valuable suggestions.