Annotated check list of the brachyuran crabs (Crustacea: Decapoda) from Gulf of Mannar region, south east coast of India

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2017; 5(6): 2331-2336 E-ISSN: 2320-7078 P-ISSN: 2349-6800 JEZS 2017; 5(6): 2331-2336 2017 JEZS Received: 18-09-2017 Accepted: 25-10-2017 V Vidhya M.F. Sc Research Scholar, Department of Fisheries Biology and Resources Management Fisheries College and Research Institute Tamil Nadu Fisheries University Thoothukudi, Tamil Nadu, India P Jawahar Professor, Department of Fisheries Biology and Resources Management Fisheries College and Research Institute Tamil Nadu Fisheries University Thoothukudi Tamil Nadu, India K Karuppasamy M.F. Sc Research Scholar, Department of Fisheries Biology and Resources Management Fisheries College and Research Institute Tamil Nadu Fisheries University Thoothukudi, Tamil Nadu, India Correspondence V Vidhya M.F. Sc Research Scholar, Department of Fisheries Biology and Resources Management Fisheries College and Research Institute Tamil Nadu Fisheries University Thoothukudi, Tamil Nadu, India Annotated check list of the brachyuran crabs (Crustacea: Decapoda) from Gulf of Mannar region, south east coast of India V Vidhya, P Jawahar and K Karuppasamy Abstract The check list of brachyuran crabs studied from Therespuram, Vellapatti, Vethalai, Periyapattinam coast of Gulf of Mannar, south east coast of India. These landing centers show the maximum crab diversity. Moreover these four regions were taken for species composition and diversity study. Totally 60 individual crab species were recorded belonging to 10 families and 24 genera from these landing centers. The maximum crab species were recorded belonging to family Portunidae than other families. Among these four landing centers maximum diversity has been observed in Vedalai followed by Therespuram. Least diversity of brachyuran crabs has been documented from Vellapatti. Twenty six species from Portunidae, 10 species from Calappidae, 6 species from Xanthidae, 4 species from Leucosidae, 3 species from Dorippidae, Majidae and Parthenopidae, 2 species from Matutidae and Carpiliidae and 1 species from Dromiidae. The crabs families viz. Portunidae, Calappidae were obtained in almost all seasons from these landing centers. Keywords: Checklist, Brachyuran crabs, Decapoda, Family, Gulf of Mannar Introduction Crustaceans are highly valuable commodities by virtue of their pivotal role in the seafood industry of the world. Many of the crabs are commercially important as a food source for people. Brachyuran crabs are a diverse group of crustaceans alive today. Crabs are one of the important faunal communities serving as a good food source to human beings in the marine and brackish water ecosystems. Crabs are one of the ecologically important faunal communities in the marine ecosystem. They are filter feeders, sand cleaners, mud, plant and carrion feeders, predators, commensals and parasites. The marine water ecosystems such as estuaries, backwaters, saltwater, lakes, mangroves etc., which form the nursery grounds of crabs, are increasingly encroached by various purposes. They are found with a higher diversity in reef environments and are also widespread on shallow shores and intertidal regions. They found at even 6000 m depths to the seas shore and are dominant in many estuarine habitats where salinity and temperatures can fluctuate dramatically daily [12]. In the present study an attempt has been made on the diversity of crabs from Gulf of Mannar region south east coast of India. Diversity of Brachyuran crabs in brackish water lakes of India [4, 27] and in the mangrove environment of Tamil Nadu was studied by various authors [5]. The brachyuran crab diversity studies are available in different areas like Arukkattuthurai Pasipattinam [28], Chennai coast [23, 15], Gulf of Mannar areas [7], Pondicherry mangrove areas [19], Pichavaram mangrove areas [1], Parangipettai coast [8, 9, 18] and also from Mudasal Odai and Nagapattinam. Besides, a general account of the crab fishery off Chennai also available for the period of 1985-95 [22]. There are 210 species of crabs were observed from Gulf of Mannar (CMFRI, 1969a and 1998) [2-3]. The dominant genera were Dromia, Cryptodromia, Ranina, Dorippe, Calappa, Scylla, Portunus, Charybdis, Thalamita, Demania, Leptodius, Atergatis, Phymodius and Doclea. In Gulf of Mannar coast, crab resources are being exploited mainly by four different types of gears viz. trawlnet in the mechanized sector and bottom-set gillnet, shore seines and thallumadi in the artisanal sector and their operation is restricted to shallow grounds up to 15 meters depth. From the previous reports on crab landings, it is observed that the berried crabs of both P. sanguinolentus and P. pelagicus are under heavy fishing pressure. The reason for the population decline in portunid species might be due to the overharvesting by efficient fishing gear, destruction of nursery habitat, harvesting ovigerous females and ~ 2331 ~

inefficiency of crab management. Many fishermen started adopting new harvesting techniques to increase the harvesting capacity. As a result, the crab stocks in many coastal areas are now in crisis. Therefore, it is necessary to conduct research on stock assessment with the goal of enhancing the local crab population. The present study aims to contribute to the knowledge of the richness of the brachyuran crabs on the waters of south east coast of India and enable to mapping the biodiversity of crabs in the Gulf of Mannar coast. Materials and methods a) Study area Gulf of Mannar covers approximately an area of 10,500 sq.km along 8 35' N - 9 25' N latitude and 78 08' E - 79 30' E longitude. Gulf of Mannar situated in the southeastern coast of India extending from Rameswaram in the north to Tuticorin in the south along with its marine environment has been declared as India's first Marine Biosphere Reserve. There are 21 islands covering an area of 623 ha. The islands are occurring in 4 groups namely Mandapam group, Keezhakarai group, Vembar group and Tuticorin group. There are no permanent inhabitants in these islands and temporary camping by forest officials and fishermen for a few days is common in some of the islands. The coral reefs are of fringing and patch types and extend from Rameswaram to Tuticorin covering a distance of 140 km. However, major part of the reef is fringing type arising from the shallow sea floor of not more than 5m in depth. About 3600 species of flora and fauna have been known to occur in this area in the past. However, this area is now facing severe threat due to destruction of sensitive ecosystems like corals and seagrass through indiscriminate and intensive trawling, coral mining, dynamite fishing etc, commercialized fishing of specific fauna such as sea fans, chanks, sea cucumber, sea horses, and endangered species like dugongs and turtles. These activities have depleted the resources and reduced the biological wealth of this region. a) Sample Collection The present study was carried out for a period of 12 months from June 2015 to June 2016 at Gulf of Mannar south east coast of India. The study area was shown in Fig.1. The crabs were collected every month of the year with a regular visit was made in 4 different landing centers. The sample stations are Theraspuram, Vellapatti, Vethalai, Periyapattinam. The first two stations Therespuram, Vellapatti are situated in Thoothukudi and Vedalai, Periyapattinam are in Rameswaram. In Theraspuram the Villanguchali (8.93 0 N and 78.26 0 E) island and Karai chali island (8.95 0 N and 78.25 0 E) are the two main fishing ground. The Vann island (Lat, 8 o 50 N and 78 o 13 E) and Koswari island (Lat, 8 o 52 N and 78 o 9 E) are the two main fishing ground in Vellapatti (Lat, 8 o 51 N and 78 o 11 E) region. At Vethalai Manoli island (9.21 0 N and 79.21 0 E) and Musal island (9.19 0 N and 79.07 0 E) and in Periyapattinam Valai island (9.18 0 N and 78.93 0 ) Mulli island (9.18 0 N and 78.96 0 E) and Musal island (9.19 0 N and 79.07 0 E) are the main fishing grounds. From these landing centers the different species of crabs were collected and identified up to the species level using some of the taxonomic keys [11, 24]. Fig 1: Sampling stations at Gulf of Mannar ~ 2332 ~ Results and Discussion In the present study totally 60 species belonging to 10 families Calappidae, Dromiidae, Matutidae, Portinidae, Carpiliidae, Xanthidae, Dorippidae, Leucosidae, Parthenopidae and Majidae and 24 genera- Portunus, Scylla, Podophthalmus, Charybdis, Thalamita, Calappa, Mursia, Lauridromia, Matuta, Carpilius, Etisus, Dorippoides, Gaillardiellus, Demania, Atergatis, Halimede, Dorippe, Leucosia, Parilia, Parthenope, Camposcia, Hyastenu, Doclea and Arcania were recorded in different stations at Gulf of Mannar (Table 1). The families were in the following descending order; Portunidae (26) > Calappidae (10) > Xanthidae (6) > Leucosiidae (4) > Parthenopidae (3) > Dorippidae (3) > Majidae (3) > Matutidae (2) > Carpiliidae (2) > Dromiidae (1). The Percentage composition of crab family representation in Gulf of Mannar region was shown in Fig.2.The family Portunidae was represented by 5 genera (Scylla, Portunus, Podophthalmus, Charybdis and Thalamita) consists of 26 species which includes (Portunus pelagicus, P. sanguinolentus, P. gladiator, P.gracilimanus, P. segnis, P. reticulatus, P. arenatus, P. haanii, P. argentatus, Scylla

tranquebarica, S. serrata, Podophthalmus vigil, C.natator, C. feriata, C. lucifera, C.granulata, C. annulata, C. japonica, C. reversandersoni, C. smithii, C. hellerii, C. variegate, Thalamita integra, T. crenata, T. admete, T. parvidens).the family Calappidae was represented by two genus consists (Calappa and Mursia) of 9 and 1 species Calappa lophos, C. gallus, C. bileneata, C. calappa, C. philargius, C. japonica, C. bicornis, C. hepatica, C. pustulosa and Mursia bicristimana. The family Matutidae was represented by a single genus (Matuta) consists of a species Matuta lunaris, M. planipes. The family Xanthidae was represented by five genus (Etisus, Gaillardiellus, Demania, Atergatis and Halimede consists of a species, Etisus denatus, Gaillardiellus rueppelli, Halimede ochtodes Demania baccalipes, Atergatis integerrimus and Atergatis subdentatus. The family Dromiidae was represented by single genus (Lauridromia) consists of a species Lauridromia dehaani. The family Dorippidae was represented by two genus (Dorippoides and Dorippe ) consists of a species Dorippoides facchino, D. quadridens and Dorippe tenuipes. The family Leucosiidae was represented by three genus (Arcania, Leucosia and Parilia) consists of a species Arcania septemspinosa, Leucosia anatum, L. craniolaris and Parilia major. The family Carpiliidae was represented by single genus (Carpilius) consists of a species Carpilius maculatus and C. convexus and the family Parthenopidae also represented by a single genus (P. longimanus, P. contraries and P. echinatus). The family Majidae represented by three genus (Camposcia retusa, Hyastenus pleione and Doclea hybrida). Table 1: Checklist & occurrence of crab species recorded during the study in different stations S. STATION Species Family No s1 s2 s3 s4 1. Portunuspelagicus(Linnaeus, 1758) Portunidae + + + + 2. Portunussanguinolentus(Herbst, 1783) + + + + 3. Portunusgracilimanus(Stimpson, 1858) + + + + 4. Portunussegnis(Forskal,1775) + + + + 5. Portunusgladiator(Fabricius, 1798) + - - - 6. Portunusreticulatus(Herbst, 1799) + + + + 7. Portunusarmatus(A. Milne-Edwards, 1861) + + + + 8. Portunushaanii(Stimpson,1858). + + + + 9. Portunusargentatus(A. Milne-Edwards, 1861) + + - + 10. Podophthalmus vigil (Fabricius, 1798) + + + + 11. Scylla serrata(forskal, 1775) + + + + 12. Scylla tranguebarica(fabricius, 1798) + + + + 13. Charybdis natator(herbst, 1794) + + + + 14. Charybdis feriatus(linnaeus, 1758) + + + + 15. Charybdis lucifera(fabricius,1798) + + - - 16. Charybdis annulata(fabricius, 1798) + + - - 17. Charybdis smithii(macleay,1838) + + - - 18. Charybdis hellerii(a. Milne Edwards, 1867) + + - - 19. Charybdis granulate (De Haan, 1833) + - - - 20. Charybdis japonica(a. Milne Edwards, 1861) + + - + 21. Charybdis reversandersoni(alock,1899) + + + + 22. Charybdis variegate (Fabricius, 1798) - - + - 23. Thalamita crenata(ruppell, 1830) + + - + 24. Thalamita integra ( Dana, 1852 ) - + - + 25. Thalamita admete (Herbst, 1803) - + - + 26. Thalamita parvidens (Rathbun, 1907) - + - + 27. Calappabileneata(Ng,Lai&Aungtonya, 2002) Calappidae + + + + 28. Calappacalappa(Linnaeus, 1758) + + + + 29. Calappaphilargius(Linnaeus, 1758) + + + + 30. Calappagallus(Herbst, 1803) + + + + 31. Calappalophos(Herbst, 1782) + + + + 32. Calappa japonica (Ortmann, 1892) + - - - 33. Calappa hepatica (Linnaeus, 1758) + + + + 34. Calappabicornis(Miers, 1884) - - + + 35. Calappapustulosa(Alcock, 1896 ) - - + + 36. Mursiabicristimana(Alock&Anderson, 1895) - - + + 37. Lauridromiadehaani(Rathbun,1923 ) Dromiidae + - + - 38. Matutaplanipes(Fabricus,1798) Matutidae - - + + 39. Matutalunaris(Forskal, 1775) - - + + 40. Carpiliusmaculatus(Linnaeus, 1758) Carpiliidae + - + + 41. Carpilius convexus (Forskål, 1775) + - + - 42. Etisus denatus(herbst, 1785) Xanthidae - + + + 43. Gaillardiellu srueppelli (Kraus, 1843) + + + + 44 Halimede ochtodes (Herbst, 1783) - + + + 45 Demania baccalipes(alcock, 1898) + + + + 46. Atergatis integerrimus (Lamarck, 1818) + - + - 47. Atergatis subdentatus (Haan, 1835) + - + - 48 Dorippoides facchino (Herbest,1785) Dorippidae + + + + 49 Dorippoides quadridens(fabricius,1793) + + + + ~ 2333 ~

50 Dorippe tenuipes (Chen, 1980) + + + + 51 Arcania novemspinosa (Lichtenstein, 1816) Leucosidae + + + + 52 Leucosia anatum (Herbst, 1783) - - + - 53 Leucosia craniolaris (Linnaeus, 1758) - - + - 54 Parilia major (Sakai, 1961) + - - - 55 Parthenope longimanus (Linnaeus, 1758) Parthenopidae - - + + 56 Parthenope contrarius (Herbst, 1804) + - + + 57 Parthenope echinatus (Herbst, 1790) + - + + 58 Camposciaretusa(L atereille,1829) Majidae + - + - 59 Hyastenus pleione (Herbst, 1803) - + + - 60 Doclea canalifera (Stimpson, 1857) - + + - Total 44 39 46 42 +: present, and -: absent Fig 2: Percentage composition of family representation in Gulf of Mannar region a) Therespuram (station -1) At station I, 9 families in 44 species of crabs were observed. The order of species abundance in different families is Portunidae > Calappidae >Xanthidae > Dorippidae > Carpiliidae >Leucosiidae > Parthenopidae > Dromiidae>Majidae > Matutidae (Table.1 and Fig.2). Fig 4: The number of familes, genera and species of crabs recorded on Vellapatti c) Vedalai (station -3) At station III, 10 families in 45 species of crabs were observed. The order of species abundance in different families is Portunidae > Calappidae > Xanthidae > Leucosiidae >Dorippidae > Parthenopidae > Majidae > Carpiliidae > Matutidae > Dromiidae (Table 1 and Fig. 4). Fig 3: The number of familes, genera and species of crabs recorded on Therespura b) Vellapatti (station -2) At station II, 8 families in 38 species of crabs were observed. The order of species abundance in different families is Portunidae > Calappidae > Xanthidae > Dorippidae > Leucosiidae > Majidae > Matutidae > Carpiliidae>Dromiidae >Parthenopidae (Table 1 and Fig. 3). Fig 5: The number of familes, genera and species of crabs recorded on Vedalai d) Periyapattinam (station -4) At station IV, 7 families in 29 species of crabs were observed. The order of species abundance in different families is Portunidae > Calappidae > Matutidae > Xanthidae > Dorippidae > Carpiliidae > Leucosiidae > Dromiidae (Table 1 and Fig. 5). ~ 2334 ~

Fig 6: The number of familes, genera and species of crabs recorded on Periyapattinam The decapod crabs are mostly active animals with complex behaviour patterns (Pillai and Nair, 1968) [14]. Crabs are one of the fascinating groups in decopoda. Brachyuran crabs, comprise about 700 genera and 5000 to 10,000 species worldwide [10, 13, 21, 12, 30], out of which 2,600 are present in Indo-West Pacific (Serene, 1968) [20]. Out of about 640 species of marine crabs so far recorded from Indian waters only 15 species are edible, which inhabit the coastal waters and adjoining brackish water environments, support commercial fisheries [16, 25, 26]. A total number of 990 species of marine brachyuran crabs belonging to 281 genera and 36 families were recorded in Indian waters by Kathirvel (2008) [11]. Suthakar (2011) [24] have been reported 72 crab species from Cuddalore coast. Recently Varadharajan (2012) [26] was reported 79 crab species coming under 21 families crabs in Palk Strait. Tamil Nadu coast, one of the state in India has 404 species of crabs belonging to 26 families and 152 genera (Kathirvel, 2008) [11]. Maximum percentages of crab catches are landed from Gulf of Mannar, Palk Bay, Nagapattinam and Puducherry landings of Tamil Nadu coast in India (Rao et al., 1973) [17]. In the present study totally 60 crab species were recorded in different station, which were represented by 10 families and 24 genera. Maximum crab species recorded in the present study was belonging to the family Portunidae than others families. Maximum species were recorded at station 3 and minimum species at station 2. The occurrence of crab species in different stations were in the following order; Vedalai (46) (Fig.5) > Therespuram (45) (Fig.3) > Periyapattinam (43) (Fig.6) > Vellapatti (39) (Fig.4). Similar observations were made by Gokul and Venkataraman (2008) [6] recorded 67 crab species in Gulf of Mannar. A check list of 162 species of hermit crabs, 3 families, 40 genera and 705 brachyuran crabs (28 families, 270 genera) were reported from India [29]. From this study, the results showed that a number of decapod species found in a given area. Yet it is not often in low diversity in areas that are in need of conservation. A value of biodiversity as an indication of environmental health and for the functioning of ecosystem. Estimation of biodiversity values in monetary terms helps to promote and justify conservation actions at the public policy and decision making level and is essential to define the optimal level of conservation. The possible conservative measures to increase the crab landings and to make it available throughout the year are given as follows The large-scale destruction of young crabs would obviously have an adverse effect on the crab resources; therefore a specific size for harvest is to be fixed. The fishing areas should be closed or the fishing effort should be minimized for a certain period of time or seasonal banning of the shipment of crabs should be done. The conservation measures for catching young, undersized and berried crabs should be done by educating the fishermen through audiovisual aids. Sea ranching should be promoted for over exploited species. And certain regulatory measures and laws should be enforced like, fixing the legal minimum size (across the broadest part of carapace) and protection of ovigerous crabs. The law breakers should be fined or punished. References 1. Ajmal Khan S, Raffi SM, Lyla, PS. Brachyuran crab diversity in natural (Pitchavaram) and artificially developed mangroves (Vellar estuary). Current Science. 2005; 88:1316-1324. 2. CMFRI. Catalogue of types of sponges, corals, polychaetes, crabs and echinoderms in the reference collection of Central Marine Fisheries Research Institute. Bulletin of the Central Marine Fisheries Research Institute. 1969a; 7:62. 3. CMFRI. In: Initial Environmental Examination of Sethusamudram Ship Canal Project Report. Compiled by CMFRI, Report submitted to NEERI, Nagpur, 1998. 4. Dev Roy MK, Nandi NC. Brachyuran biodiversity of some selected brackish water lakes of India. Proceedings of Taal. 2008, 496-499. 5. Fredrick WS, Samuthrapandian R. Diversity of Brachyuran Crabs in the Mangrove Environment of Tamil Nadu. World Journal of Fish and Marine Sciences. 2013; 5:441-444. 6. Gokul A, Venkataraman K. On some brachyuran crabs from Gulf of Mannar Marine Biosphere reserve. Training manual on GIS and Marine biodiversity (Johnmilton MC, ed). Loyola College Publication, 2008, 123-155. 7. Jeyabaskaran R, Ajmal Khan S. Diversity of brachyuran crabs in Gulf of Mannar (Southest coast of India). In: Biodiversity Conservation of Gulf of Mannar Biosphere Reserve (Kannaiyan S, Venkataraman K, eds). National Authority, Chennai, India. 2007, 68-82. 8. 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