Typhlocarcinops hirtus, Ng & Rahayu, 2020

Ng, Peter K. L. & Rahayu, Dwi Listyo, 2020, A synopsis of Typhlocarcinops Rathbun, 1909 (Crustacea: Decapoda: Brachyura: Pilumnidae), with descriptions of nine new species from the Indo-West Pacific, Zootaxa 4788 (1), pp. 1-100 : 75-78

publication ID	https://doi.org/ 10.11646/zootaxa.4788.1.1
publication LSID	lsid:zoobank.org:pub:7A461DBA-00B7-48DB-9320-4775DA8F21B2
DOI	https://doi.org/10.5281/zenodo.10564051
persistent identifier	https://treatment.plazi.org/id/03C05222-FFE8-FC41-FF35-D51DFC45FEAD
treatment provided by	Plazi
scientific name	Typhlocarcinops hirtus
status	sp. nov.

Treatment

Typhlocarcinops hirtus View in CoL n. sp.

( Figs. 62–64 View FIGURE 62 View FIGURE 63 View FIGURE 64 )

Material examined. Holotype: male (10.6 × 8.1 mm) ( MZB Cru 4810), Kuta, coll. 18 August 2006 . Paratypes: 1 female (11.4 × 8.3 mm) ( MZB Cru 4811) , 2 females (10.9 × 7.5 mm, 13.8 × 10.2 mm) ( ZRC 2018.0273 View Materials ), same data as holotype ; 1 male (11.8 × 8.1 mm) ( MZB Cru 4812), Sekotong, coll. 16 May 2009 ; 1 male (15.0 × 11.0 mm) ( ZRC 2015.0486 View Materials ), Sekotong, coll. 10 May 2007 ; 1 male (7.1 × 5.2 mm) ( ZRC 2018.0274 View Materials ), Teluk Kombal , coll. D.L. Rahayu, April 2014 ; 1 male (11.7 × 8.4 mm) ( ZRC 2015.0485 View Materials ) Jerowaru, coll. 10 May 2004 ; 1 female (8.6 × 6.1 mm) ( ZRC 2013.1756 View Materials ), Medana, coll. 12 June 2007 ; 3 males (5.3 × 4.0 mm, 5.4 × 4.0 mm, 4.5 × 3.4 mm) ( ZRC 2018.0718 View Materials ), Kuta , coll. D.L. Rahayu, 19 August 2008 . All locations in Lombok Island, Indonesia .

Diagnosis. Carapace ( Figs. 62A, B View FIGURE 62 , 63B View FIGURE 63 ) 1.4−1.5 times broader than long, surface smooth, covered with short pubescence on surface, longer plumose setae on lateral and frontal margins, regions demarcated, H-shaped gastrocardiac grooves deep, distinct, anterolateral margin arcuate, lined with small granules, granules at junction with posterolateral margin separated by shallow indentation obscured by long setae; posterolateral margin subparallel, surface and margin with scattered tubercles. Front bilobed ( Fig. 62B, C View FIGURE 62 ), with shallow median cleft, margin of each lobe convex. Orbit ( Fig. 62C View FIGURE 62 ) short, bulbous ocular peduncles filling orbit, immovable, cornea small, pigmented. Epistome ( Fig. 62C View FIGURE 62 ) relatively broad, triangular median lobe with median suture. Antennal peduncles long. Third maxilliped ( Fig. 64A View FIGURE 64 ) with outer surface of merus covered with small granules on distal margin, outer margin straight, anteroexternal angle rounded; ischium squarish, distinctly longer and slightly broader than merus; exopod relatively stout. Chelipeds in male unequal, subequal in females ( Figs. 61A, F, G View FIGURE 61 , 63B View FIGURE 63 ), fingers of major chela smooth except for few tubercles hidden by row of long setae on dorsal surface of dactylus proximally, longitudinal ridge on dactylus and fixed finger; surface of palm pubescence, and with sparse long setae, outer lower surface of palm with tubercles continued to fixed finger proximally, cutting edges of fingers with prominent broad teeth; carpus and merus pubescence, margins covered with long setae; inner angle of carpus with sharp, denticulate protuberance ( Fig. 63A View FIGURE 63 ). P2−P5 proportionally short ( Figs. 62A View FIGURE 62 , 63B View FIGURE 63 ), lateral surface, dorsal and ventral margins fringe with long setae; dactylus straight; merus of P5 not reaching front when folded. Fused thoracic sternites 1, 2 broadly triangular ( Fig. 62D View FIGURE 62 ), proportionally narrow; thoracic sternites 3, 4 partially fused, with only lateral suture discernible. Male pleon ( Figs. 62D, E View FIGURE 62 , 64B View FIGURE 64 ) relatively broad; telson long, twice length of somite 6, subtriangular. G1 ( Fig. 64 View FIGURE 64 C–F) slender, slightly curved, upper half distinctly longer than lower half, distal part slightly sinuous, tip broad, pointed upward, with rows of setae near opening. Female pleon ( Fig. 63C View FIGURE 63 ) broad, somite 1 reaching coxae of fourth ambulatory legs, tapering to pointed edge; telson subtriangular; vulva ( Fig. 63D View FIGURE 63 ) relatively broad, ovate.

Etymology. From the Latin hirtus , hairy, in allusion to the long setae covering carapace, chelipeds and ambulatory legs.

Remarks. Typhlocarcinops hirtus n. sp. is superficially similar to T. tonsuratus from Australia, which is also a distinctly tomentose species. Typhlocarcinops hirtus n. sp. can be distinguished by its more transversely rectangular carapace with the width to length ratio 1.4‒1.5 ( Figs. 62A View FIGURE 62 , 63B View FIGURE 63 ) (versus carapace more squarish with the width to length ratio 1.2 in T. tonsuratus ; Fig. 34A View FIGURE 34 ); the ischium of the third maxilliped is distinctly longer and slightly broader than the merus, with the inner and outer margins straight ( Fig. 64A View FIGURE 64 ) (versus the ischium of the third maxilliped is only slightly longer than the merus, with the inner margin of the ischium slightly oblique in T. tonsuratus ; Fig. 34B View FIGURE 34 ); and the G1 is slightly curved on the lower half, with the distal part sinuous, the tip broad and the opening has rows of setae setae ( Fig. 64 View FIGURE 64 C–F) (versus G1 strongly curved on lower half, the distal part gently curved upwards, the tip upcurved with two series of short and long setae distally in T. tonsuratus ; Fig. 34 View FIGURE 34 E–G).

The general carapace shape and degree of setation on T. hirtus n. sp. closely resembles Paraselwynia ursina Tesch, 1918 , described from nearby Kei Islands in the Moluccas. The first author managed to examine the type female (and only known specimen) and it is refigured here ( Figs. 65 View FIGURE 65 , 66 View FIGURE 66 ) as the original drawings by Tesch (1918) are somewhat schematic. Typhlocarcinops hirtus n. sp. differs from Paraselwynia ursina in having the dorsal surface of the carapace almost flat ( Fig. 62C View FIGURE 62 ) (versus prominently domed and convex in P. ursina ; cf. Fig. 65C View FIGURE 65 ); the frontal margin is distinctly bilobed with convex lobes ( Fig. 62B, C View FIGURE 62 ) (versus frontal margin almost straight and entire in P. ursina ; cf. Fig. 65B, C View FIGURE 65 ); ischium of the third maxilliped is subrectanguar with the merus quadrate ( Fig. 64A View FIGURE 64 ) (versus ischium of third maxilliped subtrapezoidal with the merus subovate in P. ursina ; cf. Fig. 66A View FIGURE 66 ); the setae are concentrated on the dorsal margin of the dactylus of the chela with the pollex mostly glabrous ( Fig. 62F, G View FIGURE 62 ) (versus both fingers of the chela covered with very dense setae which partially obscures the surfaces in P. ursina ; cf. Fig. 65F, G View FIGURE 65 ); the female pleon is narrowly ovate with the telson acutely triangular ( Fig. 63C View FIGURE 63 ) (versus female pleon broadly ovate with the telson semicircular in P. ursina ; cf. Fig. 65D View FIGURE 65 ); and the vulvae are smaller and positioned closer to the median line ( Fig. 63D View FIGURE 63 ) (versus vulvae relatively larger and positioned further apart in P. ursina ; cf. Fig. 65E View FIGURE 65 ).