Catapaguroides hirsutus, Komai & Rahayu, 2013

Komai, Tomoyuki & Rahayu, Dwi Listyo, 2013, The Hermit Crab Genus Catapaguroides A. Milne-Edwards & Bouvier, 1892 (Crustacea: Decapoda: Anomura: Paguridae) From The Bohol Sea, Philippines, With Descriptions Of Eight New Species, Raffles Bulletin of Zoology 61 (1), pp. 143-188 : 162-167

Catapaguroides hirsutus , new species

( Figs. 12–14 )

Material examined. –– Holotype: male (sl 1.3 mm), PANGLAO 2004, stn T39 , W of Pamilacan Island , 09°30.1'N, 123°50.4'E, 100–138 m, muddy sand, 4 Jul.2004, NMCR 39064.

Description. –– Ten pairs of biserial phyllobranchiate gills; third maxilliped with 2 small arthrobranchs, both weakly lamellate; cheliped with distinctly lamellate arthrobranchs; no pleurobranchs on wall of seventh thoracic somite.

Shield ( Fig. 12A ) as long as wide; anterior margins between rostral lobe and lateral projections concave; anterolateral margins slightly terraced, posterior margin roundly truncate; dorsal surface almost glabrous, with few tufts of short setae laterally. Rostrum roundly triangular. Lateral projections roundly triangular, produced to level of rostrum, without marginal or submarginal spinule.

Ocular peduncle ( Fig. 12A ) slender, subequal in length to shield, slightly constricted at midlength; dorsal surface mesially with row of 4 tufts of stiff setae increasing in length distally; cornea normally developed, rounded, not dilated, longer than wide, corneal width approximately 0.3 of peduncular length. Ocular acicle triangular, with minute submarginal spinule, separated to each other basally by basal width of 2 acicles. Interocular lobe with convex anterior surface.

Antennular peduncle ( Fig. 12A ), when fully extended, overreaching distal corneal margin by full length of ultimate segment. Basal segment with spinule proximolaterally. Ultimate segment 0.8 length of shield, slightly broadened distally in lateral view, with 2 long plumose setae at dorsolateral distal portion. Dorsal flagellum longer than ultimate peduncular segment, with distal portion more than twice length of proximal aesthetasc-bearing portion.

Antennal peduncle ( Fig. 12A ) nearly reaching distal corneal margin. Fifth and fourth segments with few short setae. Third segment with 1 prominent spine at ventromesial distal margin. Second segment with dorsolateral distal angle produced in bifid spine falling short of midlength of fourth segment; dorsomesial distal angle with minute spine. First segment unarmed. Antennal acicle slender, slightly arcuate, overreaching corneal base but not reaching distal corneal margin, terminating in slender spine, with row of short to long stiff setae over entire length. Antennal flagellum exceeding 5.0 times of shield length; articles each principally with few short setae on distal margin, about 10 articles in proximal part with few moderately long setae.

Third maxilliped moderately stout, with crista dentata on ischium consisting of 4 teeth ( Fig. 12B ). Carpus without dorsodistal spine.

Chelipeds greatly unequal in length and dissimilar ( Figs. 12C–F , 13 ). Right cheliped ( Fig. 13 ) elongate; propodalcarpal articulation rotated clockwise about 30° from perpendicular. Chela about 2.7 times longer than wide, widest at proximal to base of dactylus. Dactylus articulating obliquely with palm, about 0.6 length of palm, somewhat curved ventrally; dorsal surface convex, dorsomesial margin not delimited, unarmed; cutting edge with 3 blunt, triangular calcareous teeth, terminating in tiny corneous claw; scattered tufts of short to moderately long setae on surfaces. Palm 0.8 times longer than carpus, very slightly widened distally; dorsal surface convex, unarmed, with numerous scattered, short to long setae; dorsolateral and dorsomesial margins not delimited; lateral, mesial and ventral surfaces also with tufts of short to long setae; ventral surface slightly convex. Fixed finger with 2 blunt triangular calcareous teeth on cutting edge, terminating in minute corneous claw. Carpus subcylindrical, about 1.3 length of merus, not broadened distally, about 3.1 times longer than distal width; dorsal surface devoid of conspicuous spines, but laterally and mesially with some minute tubercles in distal half; ventrolateral distal angle and ventromesial distal margin unarmed; surfaces with numerous scattered tufts of short to long setae; dorsomesial setae in proximal onethird thickened, bristle-like. Merus with transverse rows of thick, bristle-like setae on dorsal surface; dorsodistal margin without spine; lateral surface with few tufts of setae, ventrolateral margin generally convex, with 2 small spines distally; mesial surface mostly glabrous except for ventral part, ventromesial margin with 2 small spines at distal angle; ventral surface gently convex, with numerous tufts of long setae. Ischium unarmed, but bearing long thick, bristle-like setae on dorsal margin.

Left cheliped ( Fig. 12 C–F ) slender, reaching midlength of right chela; propodal-carpal articulation without rotation. Chela not arched, 3.4 times longer than wide. Dactylus and fixed finger slightly curved ventrally, without hiatus; dactylus subequal in length to palm, unarmed, with numerous tufts of short to long setae; dorsomesial margin not delimited; cutting edge with row of minute corneous teeth, terminating in small corneous claw. Palm approximately half length of carpus; dorsal surface moderately convex, spineless; surfaces with numerous tufts of or individual short to long setae. Fixed finger with row of minute corneous teeth on distal half of cutting edge, terminating in small corneous claw. Carpus elongate, slightly widened distally, about 3.8 times longer than distal width; dorsal surface with 1 tiny spine (located distal to midlength) laterally, 3 widely spaced tiny spines mesially, and with numerous tufts of long setae (proximal setae becoming thick, bristle-like); dorsodistal margin armed with 1 small spine at mesial angle; lateral, mesial and ventral surfaces also with numerous long setae, unarmed on ventrolateral distal angle; ventral surface slightly convex. Merus with short transverse rows of short to long stiff setae on dorsal surface; dorsodistal margin unarmed; ventrolateral margin generally convex, with 2 small spines subdistally (distal spine smaller than proximal spine); ventromesial margin also convex, unarmed; ventral surface strongly convex, with numerous long setae. Ischium spineless.

Ambulatory legs ( Fig. 14A, C ) long and slender. Dactyli (Fig. B, D) 1.3–1.6 times longer than propodi, 16.0 times longer than wide, straight in dorsal view, gently curved ventrally in lateral view, terminating in long, slender corneous claws; dorsal margins each with row of stiff setae increasing in length distally, distal 6–9 setae thickened, bristle-like; mesial faces each with row of short stiff setae on midline; ventral margin with 0–1 slender submedian spine. Propodi each with pair of long, slender corneous spines flanked by 2 pairs of much shorter spines on ventrodistal margin (second) or unarmed (third); dorsal and ventral margins with sparse, short stiff setae. Carpi each with minute dorsodistal spine; sparse, short to moderately long setae on dorsal margin. Meri each with 1 tiny distal spine on ventrolateral margin (second) or unarmed (third); dorsal margins each with row of short to moderately long setae; ventral margins with sparse long setae (second) or glabrous (third). Ischia with dorsal margins naked (second) or with row of short setae (third); ventral margins with short sparse setae. Second pereopods with conspicuous notch on ventral margin at articulation between merus and ischium.

Fourth pereopod ( Fig. 12G ) semichelate; dactylus with several minute corneous teeth on ventral margin; propodal rasp consisting of 6 corneous scales arranged in single row. Fifth pereopods semichelate.

Anterior lobe of sixth thoracic sternite ( Fig. 12H ) subtrapezoidal, with minute tubercle at each anterolateral angle, slightly skewed to left, bearing moderately short setae on anterior margin.

Male with short sexual tube emanating from coxa of right fifth pereopod ( Fig. 12I ), directed from right to left, slightly thickened in distal 0.4, reaching lateral margin of coxa of left fifth pereopod. Coxa of left with short, papilla-like sexual tube directed anteromesially, partially obscured by adjacent tufts of setae. Eighth thoracic sternite ( Fig. 12I ) with single broad lobe bearing dense short setae.

Telson ( Fig. 12J ) longer than wide, narrowed posteriorly in posterior half; no lateral indentations; posterior lobes strongly asymmetrical, separated by deep median cleft; left terminal margin with 3 strong spines and laterally directed, spinose outer angle; right terminal margin strongly oblique, with 2 small spines and spinose outer angle.

Female unknown.

Colouration. –– Not known.

Distribution. –– Known only from the type locality, 100– 138 m.

Remarks. –– Catapaguroides hirsutus , new species, somewhat resembles C. iejimensis Osawa & Takeda, 2004 and C. umbra Komai, 2009 in sharing the following features: cornea normally developed and rounded; antennal peduncle not overreaching distal corneal margin; palm of left cheliped unarmed; and carpus of left cheliped armed with small spines on dorsal surface. The greatly elongate right cheliped is one of the obvious characters that differentiate the new species from the latter two species, though the elongation might be a male sexual character. Furthermore, in C. hirsutus , the palm and carpus of the right cheliped lack conspicuous spines. In the latter two species, the right palm has a dorsomesial row of spines and one proximal spine on the dorsal midline; and the carpus bears a dorsolateral row of spines in C. iejimensis , or only one spine slightly distal to the midlength in C. umbra . The ambulatory dactyli are unarmed or armed with only one submedian ventral spine in C. hirsutus , whereas they are armed with four to seven ventral spines ( C. iejimensis ) or one to three spines ( C. umbra ). The setation on the chelipeds is much more pronounced in C. hirsutus than in C. iejimensis and C. umbra . Catapaguroides iejimensis differs further from C. hirsutus in having shorter antennular peduncle (overreaching the distal corneal margin by the distal 0.7–0.8 length of the ultimate segment versus overreaching it by the full length of the ultimate segment) and the possession of a dorsodistal spine on the merus of the right cheliped. Catapaguroides umbra further differs from C. hirsutus in the non-constricted ocular peduncles and the terminal margins of the telson devoid of conspicuous spines.

This new species also resembles C. levigatus , new species. Differentiating characters between the two species are discussed under the account of the latter species.

Etymology. –– From the Latin “ hirsutus ” [= hairy], in reference to the setose chelipeds in this new species.

Figures

Fig. 12. Catapaguroides hirsutus, new species, holotype, male (sl 1.3 mm), PANGLAO 2004, stn T39, NMCR 39064. A, shield and cephalic appendages, dorsal view; B, ischium-basis of left third maxilliped, ventral view; C, left cheliped, mesial view; D, same, lateral view (setae omitted); E, same, chela, dorsal view; F, same, carpus, dorsal view; G, right fourth pereopod, lateral view; H, sixth thoracic sternite, ventral view; I, coxae of fifth pereopods and eighth thoracic sternite, ventral view; J, telson, dorsal view. Scale bars = 0.5 mm (A, C–F); 0.25 mm (B, G–J).

Fig. 13. Catapaguroides hirsutus, new species, holotype, male (sl 1.3 mm), PANGLAO 2004, stn T39, NMCR 39064. A, right cheliped, mesial view; B, same, lateral view (setae omitted); C, same, chela, dorsal view; D, same, carpus, dorsal view. Scale bar = 0.5 mm.

Fig. 14. Catapaguroides hirsutus, new species, holotype, male (sl 1.3 mm), PANGLAO 2004, stn T39, NMCR 39064. A, right second pereopod, lateral view; B, same, dactylus, mesial view; C, left third pereopod, lateral view; D, same, dactylus, mesial view. Scale bars = 0.5 mm.