Clibanarius longitarsus (De Haan)

Rahayu, D. L., 2003, Hermit crab species of the genus Clibanarius (Crustacea: Decapoda: Diogenidae) from mangrove habitats in Papua, Indonesia, with description of a new species, Memoirs of Museum Victoria 60 (1), pp. 99-104 : 100-101

Clibanarius longitarsus (De Haan)

Pagurus longitarsus De Haan, 1849: 211 , fig. 3.

Clibanarius longitarsus . — Fize and Serène, 1955: 83, fig. 11, pl.3, figs 1, 7, 10, 13.— Lee, 1969: 44.— Dechancé, 1964: 31, fig. 4.— Lewinsohn, 1969: 18.— Lewinsohn, 1982: 38.— Khan and Natarajan, 1984: 8, fig. 6.— Morgan, 1987: 172.—Haig and Ball, 1988: 163.— Rahayu and Forest, 1992: 762, figs 4b, 5b, 6b.

Material examined. Sungai Jaramaya , mud, 12 Nov 1999, 4 males, 2.8, 7.4, 8.1, 9.3 mm; 2 females, 3.0, 5.4 mm, and 8 Dec 1999, 4 females, 3.5, 3.9, 4.1, 6.5 mm, D.L. Rahayu ( PTFI) ; Ajkwa , mud, 20 Jan 2000, 1 female, 5.8 mm; 21 Jun 2000, 1 male, 8.5 mm, 2 females (1 ovigerous), 5.0, 6.9 mm, D.L. Rahayu ( MNHN) ; Kamora , sandy mud, 4 Apr 2000, 2 females 7.3 mm, and 8 Jun 2000, 1 female, 4.2 mm, D.L. Rahayu ( PTFI) ; Pulau Bidadari , sandy mud, 21 Jun 2000, 7 males, 2.8, 4.9, 5.0, 5.2, 5.6, 7.4, 9.0 mm; 6 females, 3.3, 4.2, 4.3, 4.4, 4.6, 4.7 mm, D.L. Rahayu ( RCO 0104 ) .

Diagnosis. Shield longer than broad. Ocular peduncles approximately 0.8 length of shield; ocular acicles terminating in simple or bifid spine. Antennular peduncles as long as or slightly longer than ocular peduncles. Antennal peduncles barely reaching base of cornea; antennal acicles not reaching distal margin of fourth peduncular segment. Chelipeds subequal, right slightly longer and more robust than left; dorsomesial margins of carpi each with 1 corneous-tipped spines distally; dorsal surfaces of palms and dactyls with irregular rows of sometimes corneous-tipped spines. Dactyls of second and third pereopods about 1.5 length of propodi, ventral margin with row of corneous spinules.

Colour in life. Shield mottled brown and blue or light brown with several blue patches. Rostrum, lateral projections and anterior margin between rostrum and lateral projections, white. Ocular peduncles brownish-orange, transparent, dorsoproximal surface with dark brown marking; corneas black; ocular acicles brown with white spines. Antennular peduncles brown, dorsal surface with longitudinal bluish-white stripe. Antennal peduncles brown; fourth and fifth segments brown, dorsal surface with bluish-white longitudinal stripe. First, second and third segments brown; antennal acicles brown with white spines.

Chelipeds brown with blue or blue-green tubercles and spines; spines with black corneous tips. Pereopods brown with blue and orange stripes over entire length. Lateral surfaces of meri each with oblique orange stripe; carpi with 1 orange and 1 blue longitudinal stripe on lateral faces. Propodi with 3 longitudinal stripes: 1 orange stripe bordered by fine red lines on dorsal margin; next, blue metallic median stripe bordered by dark brown lines; and 1 orange stripe next to ventral margin. Dorsal margin of dactyls each with longitudinal orange stripe, lateral face with longitudinal blue stripes bordered by dark brown lines; ventral margin whitish-orange. Mesial surfaces of carpi and meri brown with blue marking; mesial surfaces of dactyls and propodi same as lateral surfaces.

Distribution. Indo-West Pacific, from Red Sea and Indian Ocean, Malay Archipelago to Japan and Australia.

Remarks. The very common and widespread intertidal hermit crab, C. longitarsus , is very variable in coloration ( Fize and Serène, 1955; Ball and Haig, 1972; Morgan, 1987). The Papua specimens agree well with Fize and Serène’s (1955) description and illustration, and Rahayu and Forest’s (1992) illustration. Some specimens have the same coloration as described by Morgan (1987) from Darwin and Port Essington, Australia. However, most of the specimens reported herein have the coloration as described above. The blue median longitudinal stripe on the lateral face of each pereopod, a specific character of this species, is more intense in the specimens collected in dense mangrove habitats. The orange stripes on the pereopods and proximal brown fleck or spot on the dorsal surface of each ocular peduncle, have never been recorded previously.