1 Introduction

The squat lobsters include six recognized families (Chirostylidae, Eumunididae, Kiwaidae, Galatheidae, Munididae and Munidopsidae) in two super families (Chirostyloidea and Galatheioidea) of decapods crustaceans within the infraorder Anomura (Ahyong et al., 2010; Schnabel). Taxonomic and ecological interest in squat lobsters has grown considerably over the last two decades. The squat lobster genus Munida Leach, 1820 is most species-rich in the Galatheoidea, represented by 265 species worldwide (Baba et al., 2008; Macpherson, 2009; Cabezas et al., 2009; Hendrickx and Ayon Parente, 2010; Komai, 2011a; Komai, 2011b). Most species of Munida are from shelf and slope depths. The approximately 930 described species of squat lobsters are known form a wide range of depths (littoral to abyssal) and exhibit a worldwide distribution (Macpherson et al., 2010). The majority of genera have a limited overall vertical range, 31 genera are restricted to within a 1000 m depth band. Fifteen of these genera across all families comprise entirely of shallow-water species (<400 m), the chirostyloid genera Chirostylus and Hapaloptyx and the galatheoid genera Allogalathea, Allomunida, Anomoeomunida, Cervimunida, Coralliogalathea, Fennerogalathea, Lauriea, Macrothea, Nanogalathea, Neonida, Pleuroncodes, Setanida, and Sadayoshia. Records for a further twelve galatheoid genera remain within the upper 1000 m (Alainius, Babamunida, Bathymunida, Crosnierita, Heteronida, Janetogalathea, Onconida, Paramunida, Plesionida, Raymunida, Tasmanida and Torbenella). The remaining 17 genera include the most speciose taxa (Munida, Munidopsis and Uroptychus) and are recorded from deeper than 1000 m. These deep-water genera have a wide bathymetric range that includes both shelf and slope species and, in the case of Munidopsis and Galacantha, also abyssal species (with a depth range of 5–5330 m and 404–3212 m, respectively). Therefore, nearly all genera contain some shallow-water species even if the overall depth range reaches to considerable depth. Exceptions are the monotypic deep-sea genera Pseudomunida (Chirostyloidea: Eumunididae) and the hydrothermal vent Shinkaia (Galatheoidea: Munidopsidae) that are known only from few locations within a very limited depth band (Baba et al., 2008).

Taxonomical studies on the Chirostylid and Galatheid lobsters of India are dealt with by Alcock (1894 and 1901), Alcock and Anderson (1895), Doflein and Balss (1913a), George and Rao (1966), Rao (1974), Tirmizi and Javed (1993), Thirumilu, (2011), Vaitheeswaran and Venkataramani (2012); Vaitheeswaran (2014); Vaitheeswaran (2015). A total of 53 species (11 from Family: Chirostylidae and 41 from Family Munididae) are recorded, mostly from the deeper waters of Lakshadweep Sea, Arabian Sea, Bay of Bengal and Andaman Sea, while a single galatheid lobster Munidopsis regia Alcock and Anderson, 1894 and Munida curvipes  has been reported for the first time in Indian coast at Gulf of Mannar.

While examining the crustacean catches landed by larger trawlers, which operated in deeper waters off Thoothukudi, one specimen of squat lobsters was obtained. On closer examination, it was identified as Munida semoni Ortmann, 1894 and it was new to Thoothukudi waters. Thus, the total number of squat lobsters from India now rose to 53. The taxonomic and systematic position of the present species reported here is followed the new classification given by Baba (2005) for the Superfamily Galatheoidea. The present record from Thoothukudi coast of Gulf of Mannar is the first specimen from the coast of main land.

Superfamily: Galatheoidea Samouelle, 1819

Family: Galatheidae Samouelle Ahyong, 2010

Genus: Munida Whiteaves, 1874

Munida semoni Ortmann, 1894

Borradaile, 1900

Barnard, 1950

Kensley, 1981a

Macpherson and Baba, 1993

Macpherson, 1994; 1996a; 1999a; 2004

Baba, 2005

2 Materials and Methods

2.1 Materials examined

One specimen (total length 52 mm; carapace length 17 mm; weighing about 5 gm) collected from Thoothukudi beach between 08º 35' 22.5" N lat. 78º 27' 40.9" E long and 08º 31' 91.2"N lat. 78º 25' 32.7"E long at a depth of 305-310 m (Figure 1), Thoothukudi district, TamilNadu, India (Figure 2; Figure 3; Figure 4; Figure 5; Figure 6). The reference materials are deposited in the museum collections of the Department of New Drug Discovery (Marine Invertebrate Division), RARBIO Energies Private Limited, Chennai, Tamil Nadu, India.

2.2 Distribution

The present record of this species is collected from the incidental by-catch in the trawl catch off Thoothukudi coast of Gulf of Mannar from India. Munida semoni is widely distributed in the Indo-Pacific from Indonesia, New Caledonia, Vanuatu and Futuna islands 180-440 m (Macpherson and Baba, 1993; Macpherson, 1996a; Macpherson, 1999b); Fiji and Tonga, 135-417 m.

2.3 Diagnostics

The specimen examined agrees quite well with the original description and figures provided by Baba (1988) (Figure 2). Carapace, excluding rostrum, slightly longer than wide (Figure 3). Transverse ridges mostly interrupted. Secondary striae present Epigastric region with row of 6 pairs of spines flanking 2 unpaired spines behind rostrum, largest pair directly behind supraocular spines. Fourth thoracic sternite with several short arcuate striae; fifth to seventh sternites without striae and granules (Figure 6). Pereopod 1 and 2 are absent.

2.4 Description

Ground colour of carapace and abdomen light orange, with large reddish spots scattered on dorsal surfaces. Rostrum and supraocular spines light orange. Chelipeds and walking legs with reddish and whitish bands. Base of fingers whitish; distal part of carpus, merus and hand reddish.

2.5 Remarks

The specimens examined agree quite well with the original description and figures provided by Baba (1988) (Figure 2), identical to Munida heteracantha Ortmann. In the type material examined of M. semoni, however, the granules on the seventh thoracic sternite, characteristic of M. heteracantha are absent. M. semoni is close to M. oritea sp. Nov. from the Philippines and M. striola sp. Nov. from Japan and Indonesia.

One specimen (total length 52 mm; carapace length 17 mm; weighing about 5 gm) collected from Thoothukudi beach between 08º 35' 22.5" N lat. 78º 27' 40.9" E long and 08º 31' 91.2"N lat. 78º 25' 32.7"E long at a depth of 305-310 m, Thoothukudi district, TamilNadu, India. They show the second abdominal segment unarmed, the thoracic sternites moderately squamate, the distomesial spine of the basal anternnal segment overreaching the third segment, and the merus of the third maxilliped bearing a distinct spine on the extensor distal margin.

2.6 Colour

Ground colour of carapace and abdomen light orange, with large reddish spots scattered on dorsal surfaces. Rostrum and supraocular spines light orange. Chelipeds and walking legs with reddish and whitish bands. Base of fingers whitish; distal part of carpus, merus and hand reddish (Macpherson, 2004).

Acknowledgements

The author is thankful to Thiru M. Kathirvel, former Principal Scientist of Central Institute of Brackishwater Aquaculture (I.C.A.R.), Chennai, for critical reading of the manuscript and helpful suggestion for its improvement. Dr. K. Baba, Professor, Kumamoto University, Japan, has provided me with literature on squat lobsters taxonomy. I wish to thank Thiru. K. Deenadhayalan, my friend and Professional photographer, Trichy, India, for their photograph of this specimen.

References 

Alcock A., 1894, Natural history notes from H.M. Royal Indian Marine Survey Steamer “Investigator", commander R.F. Hoskin, R.N., commanding.–Series II, No. 1.On the results of deep-sea dredging during the season of 1890-91 (continued), Ann. Mag. Nat.Hist., (ser. 6), 13: 321-334

Alcock A., 1901, A descriptive catalogue of the Indian deep-sea Crustacea Decapoda Macrura and Anomala, in the Indian Museum. Being a revised account of the deep-sea species collected by the Royal Indian Marine Survey Ship Investigator, Trustees of the Indian Museum, Calcutta, pp.286

Alcock A., and Anderson A.R.S., 1894, Natural history notes from H.M. Royal Indian Marine Survey Steamer “Investigator", commander C.F. Oldham, R.N., commanding. – Series II, No. 14. An account of a recent collection of deepsea Crustacea from the Bay of Bengal and Laccadive Sea, J. Asiatic Soc. Bengal (2) (Natural History), 63: 141-185

Ahyong S.T., Baba K., Macpherson E., and Poore G.C.B., 2010, A new classification of the Galatheoidea (Crustacea: Decapoda: Anomura), Zootaxa, 2676: 57–68

Baba K., 1988, Chirostylid and Galatheid Crustaceans (Decapoda: Anomura) of the "Albatross" Philippine Expedition 1907-1910, Res. Crust., Special number 2: I-V, 1-203

Baba K., 2005, Deep-sea chirostylid and galatheid crustaceans (Decapoda: Anomura) from the Indo-Pacific, with a list of species, Galathea Report, 20: 1-17

Baba K., Macpherson E., Poore S.T., Ahyong A., Bermudez P., Cabezas C.W., Lin M., Nizinski M., Rodrigues C., and Schnabel K.E., 2008, Catalogue of squat lobsters of the world (Crustacea: Decapoda: Anomura- families Chirostylidae, Galathidae and kiwaidae), Zootaxa., 1905: 1-220

Barnard K.H., 1950, Descriptive catalogue of South African decapod Crustacea (crabs and shrimps). Annals of the South African Museum, 38: 1-837

Borradaile L. A., 1900, On the Stomatopoda and Macrura brought by Dr. Willey from the South Seas. Zoological Results Based on Material From New Britain, New Guinea, Loyalty Islands and Elsewhere, Collected During the Years 1895, 1896 and 1897, by Arthur Willey, 4: 395-428

Cabezas P., Macpherson E., and Machordom A., 2009, Morphological and molecular descriptions of new species of squat lobster (Crustacea: Decapoda: Galatheidae) from the Soloman and Fiji Islands (South-West Pacific). Zool. J. Linn. Soc. 156: 465-493

http://dx.doi.org/10.1111/j.1096-3642.2008.00492.x

Doflein F., and Balss H., 1913a, Die Galatheiden der Deutschen Tiefsee-Expedition, Wissenschaftliche Ergebnisse der Deutschen Tiefsee-Expedition auf dem Dampfer "Valdivia" 1898-1899, 20: 125-184

George M.J., and Vedavyasa Rao P., 1966, On some decapods crustaceans from the south-west coast of India, Proc. Symp. Crustacea, Mar. Biol. Ass. India., Part I: 327-336

Gordon I., 1930, On the species of the galatheid genus Eumunida (Crustacea, Decapoda), Proc., General Meetings for Scientific Business of the Zoological Society of London, 1929: 741-753

Hendrickx M.E., and Parente M.A., 2010, A new species of genus Munida Leach (Decapoda, Galatheidae) from off the west coast of Baja California, Mexico, In Fransen, C.H.J.M.S. De Grave and P. K. L. Ng (eds.), Studies of Malacostraca, Crustaceana Monogr, 14: 305-314

Kensley B., 1981a, On the zoogeography of southern African decapod Crustacea, with distributional checklist of the species. Smithsonian Contributions to Zoology, 338: 1-64

http://dx.doi.org/10.5479/si.00810282.338

Komai T., 2011a, A new species of the squat lobster genus Munida (Decapoda: Anomura: Galatheidae) from the North off Japan. In Komai, T. and H. Komatsu (eds.), New Crustaceans of Japan 2, Bull. Natn. Mus. Nat. Sci., Suppl.5: 101-108

Komai T., 2011b, Squat lobsters of the genus Munida (Crustacea: Decapoda: Anomura: Munididae) from the Ogasawara Islands, with descriptions of four new species, Mem. Natn. Mus. Nat. Sci. 47: 339-365

Macpherson E., and Baba K., 1993, Crustacea Decapoda: Munida japonica Stimpson, 1858, and related species (Galatheidae), In : A. CROSNIER (ed.), Resultats des Campagnes MUSORSTOM, vol. 10, Memoires du Museum national d'Histoire naturelle, 156: 381-420

Macpherson E., 1994, Crustacea Decapoda: Studies on the genus Munida Leach, 1820 (Galatheidae) in New Caledonian and adjacent waters with descriptions of 56 new species, In: CROSNIER A. (ed.), Résultats des Campagnes MUSORSTOM 12, Mémoires du Muséum national d'Histoire naturelle, 161: 421-569

Macpherson E., 1996a, Crustacea Decapoda: species of the genera Munida Leach, 1820 and Paramunida Baba, 1988 (Galatheidae) from the seas around the Wallis and Futuna Islands, In: Crosnier A. (ed.), Résultats des Campagnes MUSORSTOM, volume 15, Mémoires du Muséum National d'Histoire Naturelle, Paris, 168: 387-421

Macpherson E., 1996b, Crustacea Decapoda: new records of species of the genera Munida Leach, 1820 and Paramunida Baba, 1988 (Galatheidae) from New Caledonia, with the descriptions of three new species, In: Crosnier A. (ed.), Résultats des Campagnes MUSORSTOM, volume 15, Mémoires du Muséum National d'Histoire Naturelle, Paris, 168: 423-443

Macpherson E., 1999a, Crustacea Decapoda: Species of the genera Agononida Baba and de Saint Laurent, 1996 and Munida Leach, 1820 (Galatheidae) collected during the MUSORSTOM 8 cruise in Vanuatu, In: Crosnier A. (ed.), Résultats des Campagnes MUSORSTOM, Volume 20, Mémoires du Muséum National d'Histoire Naturelle, Paris, 180: 407-426

Macpherson E., 1999b, Crustacea Decapoda: Species of the genera Agononida Baba de Saint Laurent, 1996 and Munida Leach, 1820 (Galatheidae) collected during the MUSORSTOM 8 cruise in Vanuatu, In: CROSNIER A. (ed.), Résultats des Campagnes MUSORSTOM 20, Mémoires du Muséum national d'Histoire naturelle 180: 407-426

Macpherson E., 2004, Species of the genus Munida Leach, 1820 and related genera from Fiji and Tonga (Crustacea: Decapoda: Galatheidae), In: Marshall B.A., and Richer-de-Forges B. (eds), Tropical Deep-Sea Benthos, Volume 23, Mémoires du Muséum National d'Histoire Naturelle, Paris, 191: 231-292

Macpherson E., 2009, New species of squat lobsters of the genera Munida and Raymunida (Crustacea, Decapoda, Galatheidae) from Vanuatu and New Caledonia, Zoosystema, 31: 431-451

http://dx.doi.org/10.5252/z2009n3a3

Macpherson E., Richer-de-Forges B, Schnabel K. E., Samadi S, Boisselier M.C., and Garcia-Rubies A., 2010, Biogeography of the deep-sea galatheid squat lobsters of the Pacific Ocean, Deep sea Research Part 1: Oceanographic Research Paper 57: 228-238

Ortmann A.E., 1892, Die Decapoden-Krebse des Strassburger Museums, mit besonderer Berücksichtigung der von Herrn Dr. Döderlein bei Japan und bei den Liu-Kiu-Inseln gesammelten und zur Zeit im Strassburger Museum aufbewahrten Formen. IV. Die Abtheilungen Galatheidea und Paguridea. Zoologische Jahrbücher, Abtheilung für Systematik,Geographie und Biologie der Thiere., 6: 241-326

http://dx.doi.org/10.5962/bhl.part.26455

Ortmann A.E., 1894, Crustaceen, In: Semon, R. (ed.), Zoologische Forschungsreisen in Australien und dem malayischen Archipel, Denkschriften der Medicinisch-Naturwissenschaftlichen Gesellschaft zu Jena 8: 3-80

Samouelle G., 1819, The entomologists' useful compendium; or an introduction to the knowledge of British Insects, comprising the best means of obtaining and preserving them, and a description of the apparatus generally used; together with the genera of Linné, and modern methods of arranging the Classes Crustacea, Myriapoda, spiders, mites and insects, from their affinities and structure, according to the views of Dr. Leach. Also an explanation of the terms used in entomology; a calendar of the times of appearance and usual situations of near 3,000 species of British Insects; with instructions for collecting and fitting up objects for the microscope, Thomas Boys: London, pp.496

Tirmizi N. M., and Javed W., 1993, Indian Ocean galatheids (Crustacea: Anomura) Marine Reference Collection and Resource Centre, University of Karachi, Karachi, pp.147

Thirumilu P., 2011, Record of the squat lobster Munidopsis scobina Alcock, 1894 off Chennai coast, Marine Fisheries Information Service (210), pp.21

Vaitheeswaran T., and Venkataramani V. K., 2012, Three new records of squat lobsters Eumunida funambulus (Gordon, 1930) (Chirostyloidea: Chirostylidae), Agononida eminens (Baba, 1988) and Munida heterocantha (Ortmann, 1892) (Galatheioidea: Munididae) (Crustacea: Decapoda) from Gulf of Mannar, Tamil Nadu Journal of Veterinary and Animal Sciences. 8(2), March-April, pp.87-93

Vaitheeswaran T., 2014, A New record of the Squat Lobster Munidopsis cylindrophthalma (Alcock, 1894), (Crustacea: Anomura: Galatheidae), off Thoothukudi coast of Gulf of Mannar (08º 35' 22.5" N lat. 78º 27' 40.9" E long and 08º 31' 91.2" N lat. 78º 25' 32.7"E), Indian Journal of Veterinary and Animal Sciences Research, 43(3), May-June, pp.243-249

Vaitheeswaran T, 2015, Note on the Genus Munida Leach, 1820, and Description of Munida curvipes Benedict, 1902, (Crustacea: Decapoda: Galatheidae), Off Thoothukudi Coast of Gulf of Mannar, India (08º 35' 22.5" N lat. 78º 27' 40.9" E long and 08º 31' 91.2" N lat. 78º 25' 32.7"E) (310 M), International Journal of Aquaculture, Vol. 5, No. 43: 1-5

Whiteaves J.F., 1874, On recent deep-sea dredging operations in the Gulf of St. Lawrence, American Journal of Science (ser. 3), 7: 210–219