Sepia prabahari sp. nov. (Mollusca/Cephalopoda), a new species of Acanthosepion species complex from Tuticorin bay, southeast coast of India

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1 Indian Journal of Marine Sciences Vol. 31(1), March 2002, pp Sepia prabahari sp. nov. (Mollusca/Cephalopoda), a new species of Acanthosepion species complex from Tuticorin bay, southeast coast of India *N. Neethiselvan & V. K. Venkataramani Fisheries College and Research Institute, Tamil Nadu Veterinary and Animal Sciences University, Tuticorin , Tamil Nadu, India [*drneethi@yahoo.co.in] Received 22 January 2001, revised 11 October 2001 A new cuttlefish Sepia prabahari sp. nov. collected from Tuticorin bay(8 o 47 N, 78 o 9 E) is described with a comparison of the closely related species Sepia pharaonis. Sepia prabahari sp. nov. shows a clear-cut sexual dimorphism with respect to length and shape of arms. In males, first and fourth pair of arms distinctly extended and whip like. However, in females, first and fourth arms are neither distinctly extended nor whip like. Sepia prabahari sp. nov. closely resembles the juvenile of Sepia pharaonis as both of them have distinct tiger-stripe pattern on the dorsal side of the mantle. However, Sepia prabahari sp. nov. can easily be distinguished from the closely related species S.pharaonis based on the arrangement of suckers in the tentacular club. The tentacular club of S. prabahari sp. nov. is with minute suckers of equal size without any enlarged suckers, in contrast to that of S. pharaonis with big suckers, of which about 6 suckers in medial rows are much enlarged. In S.prabahari sp. nov. the left ventral arm of male is hectocotylised with 8 transverse series of normal basal suckers followed by 7 series of modified suckers, in contrast to basal transverse series of normal suckers followed by 7 series of modified suckers in S.pharaonis. Further, S prabahari sp. nov belongs to Acanthosepion species complex (Rocheburne, 1884) as its inner cone of the cuttlebone is distinct, forming rounded and cap-like cavity in contrast to that of plate like callosity in S.pharaonis and hence belongs to Sepia sensu stricto species complex. The diagnostic characters of the species belong to the Acanthosepion species complex of the genus Sepia of Indian waters with that of S. prabahari sp. nov. are also discussed. [ Key words: Sepia prabahari sp. nov., Acanthosepion species complex, description, diagnostic characters ] The distribution of 10 species of cuttlefishes of the genus Sepia Linnaeus, (Class: Cephalopoda, Family: Sepiidae) in Indian waters have been reviewed 1. Sepia stellifera Homenko and Khromov is yet another cuttlefish, which has distribution in Indian seas 2. The recent erection of new species of Indian waters is Sepia ramani from Tuticorin Bay 1. In the present study, a new species of cuttlefish belonging to genus Sepia, hitherto not recorded was encountered along Tuticorin coast (8 o 47' N; 78 o 9' E), is fully described. Morphologically this species differed from all other species of cuttlefishes already reported in Indian seas and in world waters. The new species form year round fishery along Tuticorin coast and is compared with the other closely related species of the genus Sepia such as, S. pharaonis Ehrenberg, S. aculeata Orbigny, S.brevimana Steenstrup, S. thurstoni Adam and Rees and Sepia stellifera Homenko and Khromov. Etymology We acknowledge with appreciation the keen interest evinced by Dr.V.Prabaharan, Vice-chancellor, Tamil Nadu Veterinary and Animal Sciences University for the development of Fisheries College and Research Institute, Tuticorin as a centre of National importance and are privileged to name the newly described species after him. To describe the newly erected species in detail, 50 specimens (25 males and 25 females) in fresh condition were collected covering wide range of length. For each specimen, twenty morphometric characters were measured to the nearest millimeter. The morphometric characters of both the sexes of S. prabhari sp. nov. were combined and are given in Table1, however a notable sexual dimorphism was observed in length of arms and cuttlebone characters. Hence for these characters, sexes were treated separately and shown in Table 1. Holotype LA 1 and 2 (dorsal mantle length 125 mm male; dorsal mantle length 110 mm female)

46 Indian J. Mar. Sci., Vol. 31, No. 1, March 2002 in Fisheries College and Research Institute, Reference Museum (FCRIRM) Tuticorin, Tamil Nadu, India, 12 th December, 1998, coll. N. Neethiselvan.

2 46 Indian J. Mar. Sci., Vol. 31, No. 1, March 2002 in Fisheries College and Research Institute, Reference Museum (FCRIRM) Tuticorin, Tamil Nadu, India, 12 th December, 1998, coll. N. Neethiselvan. Paratypes: (i) 46 specimens dorsal mantle length 60 mm to 130 mm with same details as above, (ii) 4 specimens (two for each sex) dorsal mantle length 100 to 125 mm deposited in Marine Biological Station Reference Museum (MBSRM) at Parangipettai (Porto-Novo), Annamalai University, India Phylum : Mollusca Class : Cephalopoda Sub class : Coledidea Order : Sepiodidea Family : Sepiidae Genus : Sepia Species complex : Acanthosepion Species : Sepia prabahari sp. nov. Type locality Tuticorin, (8 o 47' N 78 o 9' E) southeast coast of India Diagnosis Sepia prabahari sp. nov. (Fig. 1A, B) Mantle broad, ovate, broadest at the anterior end, in fresh condition, transverse-tiger stripe pattern prominent on dorsal side of mantle, head and arms in male and less distinct in female, stripes fade slightly but persist even after death, tentacular club short with minute suckers without any enlarged suckers (Fig. 2A), swimming membrane well developed but not reaching beyond the club; dorsal protective membrane broader than the ventral protective membrane, in males arms highly elongate, robust, with broad sucker bearing surface, first and fourth pair of arm distinctly extended than other arms and whip like, in females, arms soft and not robust, first and fourth arms are not distinctly extended and not whip like, however length of arms decrease in order of 4,1,3,2 in both the sexes; in females of dorsal mantle length exceeding 6 cm golden yellow coloured Nidamental glands are visible inside mantle cavity; left ventral arm in male hectocotylised, with 8 transverse series of normal basal suckers followed by 7 series of modified suckers. Hectocotylised portion with two longitudinal dorsal rows of reduced suckers and two ventral rows of normal suckers (Fig. 3A); shell relatively narrow in male and broad in female, inner cone of the shell with cavity in both sexes, limbs of inner cone broad and completely fused with outer cone (Fig. 4A, B). Description Mantle Mantle broad, oval in outline widest at anterior end maximum width % ( %) of dorsal mantle length, mid dorsal part of mantle in anterior end produced into a triangular lobe. Fig. 1 (A) Sepia prabahari sp.nov. male (dorsal view) (B) Sepia prabahari sp.nov. female (dorsal view), (C) Sepia pharaonis male (dorsal view)

male and (C) Sepia pharaonis male Fins Fin muscular, starts slightly below anterior margin of mantle about 3.

3 Neethiselvan & Venkataramani: Sepia prabahari sp. nov. 47 Fig. 2 Tentacular club of (A) Sepia prabahari sp. nov. male and (B) Sepia pharaonis male Fig. 4 Cuttlebone of (A) Sepia prabahari male (ventral view), (B) Sepia prabahari female (ventral view) and (C) Sepia pharaonis male (ventral view) Fig. 3 Hectocotilised arm of (A) Sepia prabahari sp. nov. male and (C) Sepia pharaonis male Fins Fin muscular, starts slightly below anterior margin of mantle about 3.96 % of dorsal mantle length on sides, a narrow distinct white line seen along base of fins demarcating mantle, fin width ( %) of dorsal mantle length. Funnel Funnel large, stout and thick walled reaches almost base of ventral arm, funnel locking apparatus consists of a short curved deep and broad groove, rounded anteriorly and pointed posteriorly, a short ridge on mantle highest in middle funnel valve large, rounded and triangular, funnel length % ( %) of dorsal mantle length. Head Head prominent, short, length of head as long as inter orbital width, inter orbital width % ( % ) of dorsal mantle length; eye prominent and its longitudinal diameter % ( %) of dorsal mantle length.

4 48 Indian J. Mar. Sci., Vol. 31, No. 1, March 2002 Arms Remarkable sexual dimorphism exist with respect to shape and length of arms, however arms in both the sexes are with broad sucker bearing surface and arm length, decrease in the order of 1,4,3 and 2, arms with quadriserially arranged suckers in transverse direction, arms stout at base, arm I and II arm rounded, III arm slightly flattened and ventral arms (IV) with well developed keels and tapering ends, suckers in arms quadriserially arranged and have horny rings with vertical sides, suckers in basal rows larger and get gradually reduced in size towards distal end, those at tip very minute, arms in male robust with prominent stripes on the sides,elongate and remarkably unequal in length, among the arms, first and fourth pair highly extended and whip like, more pronounced in matured males, left dorsal arm in male (I) % ( %) of dorsal mantle length, left dorso lateral arm (II) % ( %) of dorsal mantle length; left ventro lateral arm (III) % ( %) of dorsal mantle length and left ventral arm (IV) % ( %) of dorsal mantle length in female, arms soft without prominent stripes on the sides,short and sub equal in length, among the arms, though the first and fourth pair not much extended, they are not whip like, in female left dorsal arm (I) % ( %) of dorsal Table 1 Morphometric measurements of Sepia prabahari sp.nov. and Sepia pharaonis (measurements in cm) Parameters Sepia prabahari Sepia pharaonis Mean Range Mean Range Dorsal mantle length Maximum width of mantle Fin width Fin length Maximum width including fin Eye diameter Inter orbital width Free height Length of funnel Tentacle length Tentacular club length Arm characteristics(male) Left first arm length Left second arm length Left third arm length Left fourth arm length Arm characteristics(female) Left first arm length Left second arm length Left third arm length Left fourth arm length Cuttlebone characteristics(male) Cuttlebone length Cuttlebone width Length of loculus Striated zone length Inner cone length Cuttlebone characteristics(female) Cuttlebone length Cuttlebone width Length of loculus Striated zone length Inner cone length

5 Neethiselvan & Venkataramani: Sepia prabahari sp. nov. 49

6 50 Indian J. Mar. Sci., Vol. 31, No. 1, March 2002 mantle length, left dorso lateral arm (II) % ( ) of dorsal mantle length; left ventro lateral arm (III) % ( %) of dorsal mantle length and left ventral arm (IV) % ( %) of dorsal mantle length. Hectocotylus Left ventral arm in male is hectocotylised, with 8 transverse series of normal basal suckers followed by 7 series of modified suckers. Hectocotylised portion with two longitudinal dorsal rows of reduced suckers and two ventral rows of normal suckers separated by a fleshy ridge (Fig. 3A). Tentacles Tentacles in both sexes stout, short does not exceed body length, tentacle length % ( %) of dorsal mantle length, tentacular stem thick and triangular in cross section, tentacular club short and broad, club length % ( %) of dorsal mantle length, swimming membrane remarkably broad and at the middle gradually tapers towards posterior end, dorsal protective membrane broader than ventral protective membrane extend slightly beyond carpus and not united at base, club with numerous suckers of minute size, arranged in 6 longitudinal definite rows, sucker rings with wavy end without any denticulation (Fig. 2A). Buccal membrane Mouth opening broad exposing the beak, buccal membrane thick, rostrum of horny beak dark coloured, embedded in buccal mass seen in middle. Colour Body darkish brown with distinct stripes in live condition, prominent conspicuous transverse tiger-stripes on dorsal side of mantel, head and arms in male, tiger-stripes less distinct in female, colour gets faded after death and colour changes to greenish yellow on preservation in ice, colour pattern variable depending upon degree of freshness. Though the colour gets slightly faded on preservation in formalin, the stripes persist distinctly even after preservation. Cuttlebone Cuttlebone elongate, elliptical in shape, dorsal surface convex, rugose in texture having three longitudinal faint ribs, chitinous outer edges on dorsal side broad, pale yellowish brown in fresh condition and becomes dark brown on drying, margin of chitinous part with narrow transparent rim, ventral surface of cuttlebone has a wide, deep, longitudinal groove in middle, running along entire length of striated zone, striae of growth lines distinctly inverted V shaped with undulations, inner cone of the shell with cavity and hence belong to Acanthosepion species of the complex of the genus Sepia 2, broad limbs of inner cone completely fused with outer cone and white in colour, spine short curved upward and without any keel, cuttlebone relatively narrow in male, cuttlebone width 34.78% ( %) cuttlebone length (CBL), length of loculus % ( ) of CBL striated zone length about % ( %) of CBL; inner cone length 6.45 % ( %); cuttlebone relatively broad in female, width % ( %) of cuttlebone length (CBL), length of loculus % ( %) of CBL striated zone length about % ( %) of CBL; inner cone length 4.98 % ( %) of CBL. Affinity Sepia prabahari sp. nov. closely resembles the juvenile of Sepia pharaonis as both of them have distinct tiger-stripe pattern on the dorsal side of the mantle and persist even after death and preservation in formalin. Since there was no noticeable sexual dimorphism in S.pharaonis with respect to external morphology the male specimen of this species alone is illustrated in Fig. 1C. Further, the suckers of tentacular club of S. prabahari resembles that of Sepia aculeata, Sepia brevimana and Sepia thurstoni and Sepia stellifera as these species also have numerous minute suckers on the club without any enlarged suckers. With respect to shell characters also, S. prabahari resembles S.aculeata, S. brevimana S. thurstoni and S. stellifera,as they have distinct inner cone forming rounded cape like cavity and hence belong to Acanthosepion species complex of the genus Sepia 1. The morphometric characters of both sexes of S.pharaonis are given in Table1. The diagnostic characters of Sepia prabahari sp.nov. with that of the other closely related species are given in Table 2. Sepia prabahari sp.nov. distinctly differs from S.pharaonis in all the morphometric characters (Table 1) as the S. prabahari sp.nov. reaches a maximum length of 12.5 cm and S.pharaonis reaches the maximum length of 30 cm. Further, S. prabahari differs from S. pharaonis (Table 2) in the following morphological characters:(i)the tentacular club of S. prabahari sp. nov. is with minute suckers of equal size without any enlarged suckers, in contrast to that of S. pharaonis with big suckers and of which about 6 suckers in two medial rows are much enlarged (Fig. 2B). (ii) Sepia prabahari sp. nov. belongs to Acanthosepion species

7 Neethiselvan & Venkataramani: Sepia prabahari sp. nov. 51 complex (Rocheburne, 1884) as its inner cone of the cuttlebone is distinct, forming round and cap-like cavity in contrast to that of with plate like callosity in S. pharaonis and hence S. pharaonis belongs to Sepia sensu stricto species complex (Fig. 4C). (iii) In S. prabahari sp. nov. the left ventral arm of male is hectocotilised with 8 basal transverse series of normal suckers followed by 7 series of modified suckers however, there are basal transverse series of normal suckers followed by 7 series of modified suckers in the hectocotilised arm of S. pharaonis (Fig. 3B). (iv) Sepia prabahari shows sexual dimorphism in cuttlebone characters and in length of arms, the first and fourth pair of arms are whip like in S. prabahari sp.nov especially in matured animals (Fig. 1A). However, such sexual dimorphism in length of arms are not seen in S. pharaonis. (v) In S. prabahari sp. nov. golden yellow coloured nidamental glands are visible through the mantle cavity in females of dorsal mantle length exceeding 5 cm, whereas in females of S.pharaonis, the Nidamental gland turns distinctly golden yellow only in specimens exceeding the dorsal mantle length of 12 cm. Sepia prabahari sp. nov. differs from, Sepia ramani in most of the morphological characters (Table 2). The newly erected species can be distinguished from the other closely related species belonging to the Acanthosepion species complex of the genus Sepia, reported in Indian waters viz. Sepia aculeata, Sepia brevimana and Sepia thurstoni particularly in the arrangement of suckers in hectotocotylised arms (Table 2). Sepia prabahari sp. nov. differs from Sepia stellifera by having distinct tiger stripe pattern on the dorsal side of the mantle. Acknowledgement Our grateful thanks to Prof.V. Ramaiyan, Former Director, Centre for Advanced Studies in Marine Biology, Parangipettai (Porto-Novo), for critically going through the manuscript and for his valuable suggestions. Our thanks are due to Dr. R. Sarvesan, CMFRI, Chennai for valuable suggestions and encouragements. Thanks are due to Dr. M. J. Sweeny, Smithsonian Institute, Washington, USA for having provided the information pertaining to the taxonomy of cuttlefishes of world waters. We sincerely thank Dr. V. Sundararaj, Dean, Fisheries College and Research Institute, Tuticorin for his encouragement and providing facilities. Assistance rendered by Mr. T. Vaitheeswaran and, Mr. S. Venice Selvam in the collection of data and preparation of drawings is acknowledged with thanks. References 1 Neethiselvan N, A new species of cuttlefish Sepia ramani sp. nov. (Class: Cephalopoda) from Tuticorin Bay, south east coast of India. Indian J Mar Sci, 30 (2001) Khromov D N, Lu C C, Guerra A, Dong Z & Boletzky S V, A synopsis of Sepiidae outside Australian waters (Cephalopoda : Sepioidea). in Systematics and biogeography of cephalopods edited by Voss, N A, Vecchione M, Toll,R B& Sweeny M J, Smithsonian Contribution to Zoology, N0. 586, vol 1, (Smithsonian Institution Press, Washington), 1998, pp Jothinayagam J T, Cephalopoda of the Madras coast, Zoological Survey of India Technical monograph No. 15 (1987) pp Silas E G, Sarvesan R, Rao K S, Nair K P & Meiyappan M M, Identity of common species of cephalopods of India, Bull Cent Mar Fish Res Inst, 37 (1985) Adam W & Rees W J, A review of the cephalopod family Sepidae, Scientific Reports of the John Murray Expedition , 11(1) (1966) 1-165,46 plates.

UPOGEBIA LINCOLNI SP. NOV. (DECAPODA, THALASSINIDEA, UPOGEBIIDAE) FROM JAVA, INDONESIA

NOTES AND NEWS UPOGEBIA LINCOLNI SP. NOV. (DECAPODA, THALASSINIDEA, UPOGEBIIDAE) FROM JAVA, INDONESIA BY NGUYEN NGOC-HO i) Faculty of Science, University of Saigon, Vietnam Among material recently collected