New records
of hermit crabs, Calcinus morgani Rahayu &
Forest, 1999 and Diogenes klaasi Rahayu &
Forest, 1995 (Crustacea: Anomura: Diogenidae) from India
R. Reshmi 1 &
A. Bijukumar 2
1,2 Department of Aquatic Biology &
Fisheries, University of Kerala, Thiruvananthapuram, Kerala 695581, India
Email: 1 resmirema@gmail.com 2 abiju@rediffmail.com
(corresponding author)
Date of publication (online): 26 May 2011
Date of publication (print): 26 May 2011
ISSN 0974-7907 (online) | 0974-7893 (print)
Editor: D.L. Rahayu
Manuscript details:
Ms
# o2629
Received
19 November 2010
Final
received 04 March 2011
Finally
accepted 06 May 2011
Citation: Reshmi, R. & A. Bijukumar (2011). New records of hermit
crabs, Calcinus
morgani Rahayu
& Forest, 1999 and Diogenes klaasi Rahayu & Forest, 1995 (Crustacea: Anomura: Diogenidae) from
India. Journal
of Threatened Taxa3(5): 1771–1774.
Copyright: © R. Reshmi & A. Bijukumar 2011. Creative Commons Attribution
3.0 Unported License. JoTT allows unrestricted use of this article in any
medium for non-profit purposes, reproduction and distribution by providing
adequate credit to the authors and the source of publication.
Acknowledgements: The authors thank Kerala State Council for Science, Technology and
Environment for financial support of the work. We are thankful to Dr. D.L.
Rahayu, Research Centre for Oceanography, Nusa Tenggara Barat, Indonesia for
confirming the identification and for the research publications.
Anomuran
crabs, a group of attractive and ubiquitous organisms in Crustacea, are best described as having an assortment
of adult body shapes from lobster-like to true crab-like; there is marked
reduction of fifth pereopods that are not used as ambulatory appendages, the
articulated or missing eighth thoracic sternite and the cephalothorax that is
not fused to the epistome as it is in brachyurans (McLaughlin et al.
2010). Anomura is represented by
seven super families: Aegloidea, Galatheoidea, Chirostyloidea, Hippoidea,
Lomisoidea, Lithodoidea and Paguroidea. Super family Paguroidea includes hermit crabs and their relatives in the
families Coenobitidae, Diogenidae, Paguridae, Parapaguridae, Pylochelidae and
Lithodidae. Hermit crabs of the
family Diogenidae, commonly called ‘left handed crabs’ have appreciably larger
left chela than right chela (McLaughlin et al. 2007). The genus Calcinus possesses triangular rostrum, without moveable rostriform process
developed between ocular acicles, while the genus Diogenes has rostrum rounded or
obsolete; with movable rostriform process, well developed or reduced, between
ocular acicles (McLaughlin 2002). Two species of hermit crabs of the genus Calcinus (C. herbstii and C. gaimardi) and eight species of Diogenes (D. avarus, D. costatus, D. custos, D. diogenes, D. merguiensis, D. miles, D. planimanus and D. rectimanus) have been recorded so far
from India (Khan & Natarajan 1984; Thomas 1989). This paper records the
occurrence of two species of hermit crabs, Calcinus morgani Rahayu & Forest and Diogenes klaasi Rahayu & Forest from
the southwestern coast of India.
1. Calcinus
morgani Rahayu & Forest, 1999 (Image 1 A–F)
Calcinus gaimardii Alcock, 1905: 56, pl 5,
fig. 5 (not Calcinus gaimardii (H. Milne Edwards, 1848); Calcinus gaimardi Fize & Serene, 1955:
49 (in part), text figs.7,8, pl. 2, figs. 5,6; Calcinus morgani Rahayu & Forest, 1999:
465, figs. 1B, 2C, D, G, H, 3; - Komai, 2004: 35, figs 1-9; Calcinus areolatus Rahayu & Forest, 1999:
468, fig.4.
Materials examined: Five specimens, two males
(shield length 7.1–8.0 mm), and three females (shield length 6.0–7.0
mm) collected from intertidal rocky pools of Thirumullavaram Beach, Kollam
District, Kerala, India (08053’32.5”N & 76033’18.4”E). The reference materials are deposited
at the Zoological Survey of India Regional Station, Kozhikode, Kerala (No.
ZSI/WGRC/IR/INV/2326) and the museum collections of the Department of Aquatic
Biology and Fisheries, University of Kerala (AR AN 5-6), India. The hermits were collected from the
gastropod shells of Trochus radiatus and Turbo brunneus.
Diagnosis: Shield gray; ocular
peduncles dark brown at proximal end and blue distally, with black rings below
corneas. Antennular peduncles dark
brownish-green and flagella light yellow. Antennal peduncle and flagella yellowish-orange. Chelipeds reddish-brown
with white tips. Ambulatory legs
reddish-brown, with light brown propodi and dactyli; dactyls with white tips
(Image 1A). Shield longer than
broad with rostrum acutely triangular.
Ocular peduncles long,
slender, overreaching both antennal and antennular peduncles (Image 1B). Ocular acicle terminating in a single
spine. Antennular peduncle longer
than antennal peduncle. Antennal
acicle overreaching proximal margin of ultimate peduncular segment terminating
in single spine and with 5–7 spines laterally. Fourth antennal segment with a small dorsodistal spine; the
outer margin of the first segment with a bifid spine dorsolaterally and the
inner margin with a simple spine. Chelipeds unequal, left larger than right. Outer surface of left chelae covered with closely-spaced
tubercles becoming prominent on fixed finger and dactyl. Carpus with dorsodistal spine and
prominent tubercle on middle proximal end (Image 1C). Right cheliped also with tubercles on upper surface of chela
(Image 1D). Ambulatory legs
smooth. Meri of second and third
pereopods with a spine at inner distal portion. Carpi of both pereopods with strong dorsodistal spine with
sometimes a small spine present below the dorsodistal spine on the second
pereopod. Dactyls shorter than
propodi. Brush of long plumose
setae on ventral margins of dactyls and distal part of propodus of third
pereopod (Image 1E). Telson with 2–10 spines on left lobe and 1–4
on right lobe (Image 1F).
Remarks: Calcinus morgani is widely distributed in the Indo-Pacific; inter-tidal and
sub-tidal waters of South Africa, Somalia, Madagascar, Australia, New Guinea, Indonesia,
Malaysia, Vietnam, Southern Japan, Vanuatu, Marianas, French Polynesia, Fiji
(McLaughlin et al. 2007). The
present record of this species from the southwestern coast of India shows its
extended distribution in the western Indian Ocean, from the eastern coast of
Africa to India.
2. Diogenes klaasi Rahayu & Forest,
1995
(Image 2A–E)
Clibanarius
padavensis Nateewathana et al. 1981: 51 (in part), 1981, Not Clibanarius
padavensis De Man, 1888; Diogenes klaasi Rahayu and Forest 1995: 395, fig. 3; McLaughlin, 2002: 419, figs.
3D-F.
Materials examined: Two males (shield length
2.5–2.7 mm) collected from the mangrove swamps of Dalavapuram (08056’50.7”N
& 76033’17.2”E), Kollam District, Kerala, India. The reference materials are deposited
at the Zoological Survey of India Regional Station, Kozhikode, Kerala
(ZSI/WGRC/IR/INV/2086) and at the museum collections of Department of Aquatic
Biology and Fisheries, University of Kerala (AR AN 7-8), India. The hermits were collected from the
gastropod shell of Cerithiacea cingulata and Turris nelliae.
Diagnosis: Shield reddish-orange. Ocular peduncles light greenish-orange
with antennules and antennae pale yellow. Chelipeds dark brownish-green. Ambulatory legs pale yellow with
irregular dark green spots seen in different segments (Image 2A).
Shield longer than broad,
rostrum bluntly triangular, not reaching up to ocular acicle projections. Ocular peduncles stout and cylindrical
(Image 2B). Ocular acicle with 1–3
large spines and few smaller spinules. Antennular peduncle long, slender, overreaching corneas by 0.5 length of
ultimate peduncular segment. Antennal peduncle slightly shorter or longer than
ocular peduncles; antennal acicles overreaching mid-length of fourth peduncular
segment and with 3–4 marginal spines and additional spine on dorsal
surface. Antennal flagella with long setae. Upper and lower margins of left cheliped with irregular row
of spines. Palm convex; outer
surface with small spines or tubercles and meadian longitudinal row of
spines. Carpus spinulose on outer
surface (Image 2C). Right chela
slender. Carpus with dorsodistal
spine. Ambulatory legs thin,
slender and dactyls longer than propodi. Carpi of second and third pereopod with dorsodistal spine and additional
spine at the proximal end of carpus of second pereopod (Image 2D). Chelipeds and ambulatory legs covered
with long setae. Telson broad and
asymmetrical with small median cleft. Left lobe larger than right with oblique terminal margin and 2–5
large spines laterally and few spinules; right lobe with 1–3 larger
spines laterally and few smaller spinules on terminal margin (Image 2E).
Remarks: Diogenes klaasi was originally described by
Rahayu & Forest (1995) from Indonesian shallow waters. This species is also reported from western Thailand and
Pakistan (Siddiqui et al. 2004). The present record of this species from the Ashtamudi Lake of Kerala
State, India, shows its extended distribution in the Indian subcontinent.
References
Khan, S.A. & R.
Natarajan (1984). Hermit crabs of Proto Novo Coast. Records of the
Zoological Survey of India, Occasional Paper 67: 25pp.
McLaughlin, P.A.
(2002). A review of the hermit crab (Decapoda: Anomura: Paguridea) fauna
of southern Thailand, with particular emphasis on the Andaman Sea and
description of three new species. Phuket Marine Biological Center Special Publication 23(2): 385–460.
McLaughlin, P.A., D.L.
Rahayu, T. Komai & T.Y. Chan (2007). A Catalog of the Hermit Crabs (Paguroidea) of Taiwan. Keelung Place, National
Taiwan Ocean University, 365pp.
McLaughlin, P.A., C.B.
Boyko, K.A. Crandall, T. Komai, R. Lemaitre, M. Osawa & D.L. Rahayu (2010).Annotated
checklist of anomuran decapod crustaceans of the world (exclusive of the
Kiwaoidea and families Chirostylidae and Galatheidae of the Galatheoidea) –
Preamble and Scope. The Raffles Bulletin of Zoology Supplement 23:1–4.
Rahayu, D.L. & J.
Forest (1995). Le genre Diogenes (Decapoda, Anomura, Diogenidae) en Indonesie, avec la description
de six especes novellas. Bulletin du Museum National d’Histoire Naturelle (4)16(A): 383–415.
Rahayu, D.L. & J.
Forest (1999). Sur le statut de Calcinus gaimardii (H. Milne Edwards, 1848) (Decapoda, Anomura, Diogenidae) et
description de deux especes nouvelles apparentees. Zoosystema 21: 461–472.
Siddiqui, F.A., Q.B.
Kazmi & P.A. McLaughlin (2004). Review of the Pakistani species of Diogenes Dana 1851 (Decapoda
Anomura Paguroidea Diogenidae). Tropical Zoology 17: 155–200.
Thomas, M.M. (1989). On a collection of hermit crabs from the Indian waters. Journal of Marine Biological Association of India 31(1&2): 59–79.