Scandarma splendidum Naruse and Ng, 2007

Naruse, Tohru & Ng, Peter K. L., 2020, Revision of the sesarmid crab genera Labuanium Serène and Soh, 1970, Scandarma Schubart, Liu and Cuesta, 2003 and Namlacium Serène and Soh, 1970 (Crustacea: Decapoda: Brachyura: Sesarmidae), with descriptions of four new genera and two new species, Journal of Natural History (J. Nat. Hist.) 54 (7 - 8), pp. 445-532 : 497-498

Scandarma splendidum Naruse and Ng, 2007

Scandarma splendidum Naruse and Ng, 2007, p. 337 , figs 1–3 [type locality: Bako National Park , Sarawak, Malaysia]; Ng et al. 2008a, p. 223; Lai and Olesen 2016, p. 72.

Material examined

Holotype. ZRC 2002.0265 , 1 male, 19.1 × 18.5 mm, Bako National Park , Sarawak, Malaysia, 15 March 2002.

Paratypes. ZRC 2007.0102 , 2 males, 18.0 × 20.0, 18.1 × 19.1 mm, Bako National Park , Sarawak, Malaysia, 13 September 2001 .

Others. ZRC 2011.1013 , 2 males, 10.2 × 11.3, 15.4 × 16.9 mm, 2 females, 11.8 × 12.8, 12.2 × 13.1 mm, Bako , Sarawak, Borneo, coll. May 2002; RUMF-ZC-4985, 1 male, 16.6 × 18.3 mm, 1 female, 11.8 × 12.9 mm, same as ZRC 2011.1013 .

Diagnosis

Carapace squarish, external orbital angle triangular, lateral margins slightly convex; 2 pairs of postfrontal lobes present, lateral lobes slightly exceeding mesial lobes anteriorly; anterior margins of all lobes far from frontal margin in dorsal view. Palm of male chela swollen; outer surface granulated, granules smaller on lower part, with small median protuberance on proximal part of smooth sloping area around bases of fingers; upper surface with 1 straight, longitudinally traversing row of densely packed small granules, and with several short, oblique rows on inner side. Immovable finger almost straight, gradually tapering towards tip, occlusal margin lacking marked proximal elevation, lined with small teeth on proximal two-fifths, 1 large tooth submedially, followed distally by 2 or 3 smaller teeth, subdistally with 1 large tooth and 1 low tooth; lower margin with irregular row of small teeth. Movable finger curved downwards; occlusal margin lined with 2 proximal teeth, followed distally by small teeth, and 1 subdistal tooth; inner side of upper margin with regularly lined rounded granules, these granules indistinct distally. Subdistal tooth of movable finger fitting between 2 subdistal teeth of immovable finger when closed. Male pleonal somite 3 widest, somite 4 abruptly narrowed distally, lateral margins of somites 3–5 clearly concave. G1 short, almost straight, stout, narrowed medially, distal end with anterolaterally directed narrow corneous process. Vulvae located on distal two-fifths of sternite 6, anterior margin adjacent to thoracic sternal suture 5/6, ellipsoidal, margin rimmed posteriorly, sternal vulval cover developed from posterolateral corner, covering almost entire vulva, except for anteromesial hole, cover produced ventroanteriorly as trigonal pyramid structure.

Colouration

In life, anterior half of carapace (suborbital to pterygostomial regions and frontal to epibranchial regions), chelipeds and third maxillipeds reddish, gradually changing from darker anterior inner parts (chelae and third maxillipeds) to orange posterior outer parts. Posterior half of dorsal surface of carapace varying from cream to dark khaki mixed with dark purple patterns. Ambulatory legs dark purple. See Naruse and Ng (2007, p. 338, fig. 1).

Distribution

Known only from Sarawak, Malaysia [type locality: Bako National Park] ( Naruse and Ng 2007).

Remarks

Scandarma splendidum is morphologically closest to Sc. raymondi . Among the five diagnostic characters listed by Ng (2013, p. 293), the distal corneous part of the G1 was described as being relatively wider in Sc. raymondi than in Sc. splendidum . A reexamination of the present material, however, shows that the comparative characters were inadvertently transposed by Ng (2013) and that Sc. splendidum is actually the one with a proportionately wider distal corneous part of the G1.

Ecological note

Naruse and Ng (2007, p. 338) reported that Sc. splendidum was nocturnal and observed on plants to a height of 2 m near streams or puddles, and sometimes found up to 10 m from any water source. They also commented that the ecology and behaviour of Sc. splendidum are similar to those of Sc. lintou in most aspects.