Lepidocephalus macrochir (Bleeker, 1854)

Deein, Gridsada, Tangjitjaroen, Weerapongse & Page, Lawrence M., 2014, A revision of the spirit loaches, genus Lepidocephalus (Cypriniformes, Cobitidae), Zootaxa 3779 (3), pp. 341-352 : 342-344

Lepidocephalus macrochir (Bleeker, 1854)

Indonesian Spirit Loach

( Fig. 1B )

Cobitis macrochir Bleeker, 1854:97 . Type-locality: Java ( Surakarta ) in fluviis; Sumatra (Palembang) ubi confluunt flumina Lematang et Enim. [Confluence of Lamatang and Enim rivers, Palembang, eastern Sumatra; Pepeh River, Surakarta, central Java, Indonesia]. Syntypes: originally 5; only BMNH 1866.5 .2.55 known.

Lepidocephalus macrochir . — Bleeker, 1860:70.

Diagnosis. A species of Lepidocephalus that is readily distinguishable ( Fig. 1 , Table 1 ) from L. spectrum by the presence of eyes and dark pigment on the body, and absence of tubules along the lateral line; from L. pahangensis by the presence of scales on top of the head; from L. pallens by having the dorsal-fin origin well behind (vs. over) the pelvic-fin origin (predorsal length 65.0–69.3 vs. 59.9% SL); and from L. nanensis by having a shorter snout (3.9–5.1 vs. 5.6–7.4% SL; 23.3–27.1 vs. 28.6–38.1% HL). Lepidocephalus macrochir further differs from L. pahangensis in having 8 (vs. 9) branched dorsal-fin rays and 5–6 (vs. 4) branched anal-fin rays, and from L. pallens , L. pahangensis and L. spectrum in having a shorter head (16.6–18.8 vs. 23.2, 21.8, and 21.3–23.2% SL, respectively).

Description. Body deep, slab-sided; greatest depth 15.7–18.9% SL. Head narrow, length 16.6–18.8% SL. Eye small, in dorsal half of head in shallow depression above bifid suborbital spine. Origin of dorsal fin behind origin of pelvic fin. Small axillary lobe on pelvic fin; small fleshy lobe at origin of pectoral fin. Pectoral fin falcate.

Scales on top of head, cheek and opercle; body completely covered with minute, often deeply embedded scales. Lateral line complete, 105–150 pores; no tubules on lateral line. Mouth horseshoe-shaped; upper lip without median indentation; lower lip with median indentation on lower edge. Two pairs of rostral barbels; inner pair reaching to corner of mouth, outer pair slightly longer and reaching slightly past corner of mouth; one pair of maxillary barbels, reaching approximately to vertical at posterior end of groove containing suborbital spine. Large flap on anterior nostril. Dorsal rays iii,8; pectoral rays 10–11; pelvic rays 6–8; anal rays ii,5–6; upper branched caudal rays 7–8; lower branched caudal rays 7.

Coloration. Described by Bleeker (1854) as “"colore corpore pinnisque fuscescente-aurantiaco vel fusco; maculis vel vittis corpore pinnisque nullis,” which translates to: body and fins brown-orange or brown tinged with grayish-black; lacking spots or bands on body and fins.

Distribution. Lepidocephalus macrochir is poorly represented in collections and known only from the Lamatang and Enim rivers in eastern Sumatra, the Pepeh River in central Java, and the Barito River basin in southern Borneo ( Fig. 2 ). Previous reports of the distribution that included peninsular Malaysia and western Borneo (e.g., Roberts, 1989) were based on the holotypes of L. pahangensis , and L. pallens , respectively. The occurrence of L. macrochir in the Barito River basin in southern Borneo and the Pepeh River in central Java supports the hypothesis of de Bruyn et al. (2013) of a paleo East Sunda River basin connecting these land masses.

Figures

FIGURE 1. Species of Lepidocephalus. (A) L. nanensis, holotype, NIFI 4388, 72.0 mm SL, Nan River, Thailand; (B) L. macrochir, syntype, BMNH 1866.5.2.55, 77.7 mm SL, Sumatra or Java; (C) L. pallens, holotype, RMNH 7783, 41.9 mm SL; (D) L. pahangensis, holotype, ZRC 490, 35.8 mm SL; (E) L. spectrum, paratype, USNM 230267, 49.2 mm SL, Kalimantan. Photos A, C, D and E by Z. Randall; B by M. Sabaj Perez.

FIGURE 2. Distribution of specimens of Lepidocephalus examined.