Lepidocephalus spectrum Roberts 1989

Deein, Gridsada, Tangjitjaroen, Weerapongse & Page, Lawrence M., 2014, A revision of the spirit loaches, genus Lepidocephalus (Cypriniformes, Cobitidae), Zootaxa 3779 (3), pp. 341-352 : 349

Lepidocephalus spectrum Roberts 1989

Blind Spirit Loach

( Fig. 1E )

Lepidocephalus spectrum Roberts, 1989:106 . Type locality: Rocky ledge in middle of Sungai Melawi near confluence with Kapuas mainstream, about 0.5 km upstream from Sintang. Holotype: MZB 3533 .

Diagnosis. A species of Lepidocephalus that is readily distinguishable ( Fig. 1 , Table 1 ) from other all species of Lepidocephalus by the absence of eyes, absence of dark pigment on the body, and presence of pored tubules along the lateral line. It further differs from L. pahangensis by the presence of scales on top of the head, from L. pallens by having the dorsal-fin origin slightly behind (vs. over) the pelvic-fin origin (predorsal length 62.4–65.6 vs. 59.9% SL), from L. nanensis by having large papillae on the lips ( Figs. 3C , 4B ), and from L. macrochir by having a longer head (21.3–23.3 vs. 16.6–18.80).

Description. Body deep, slab-sided; greatest depth 18.9–22.1% SL. Head narrow, length 21.3–23.3% SL. Eye absent; small shallow depression above bifid suborbital spine where eye located on other species of Lepidocephalus . Origin of dorsal fin slightly behind origin of pelvic fin. Small axillary lobe on pelvic fin. Large fleshy lobe at origin of pectoral fin.

Scales on top of head, cheek and opercle; body completely covered with minute, deeply embedded scales. Lateral line complete, 70–87 pores at ends of ventrally directed tubules along lateral line, 0–2 pores on caudal fin.

Mouth horseshoe-shaped; lips with large papillae on outer surfaces; upper lip without indentation; lower lip with median indentation on lower edge ( Figs. 3C , 4B ). Two pairs of rostral barbels; inner pair reaching to corner of mouth, outer pair reaching 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,8–9; pectoral rays 11–13; pelvic rays 6–7; anal rays ii,5–6; upper branched caudal rays 7–8; lower branched caudal rays 7–8; vertebrae 28 abdominal + 14–15 caudal = 42–43 total ( Roberts 1989:96). Pectoral fins less falcate than in other species; 2 nd ray longer than other rays. Pectoral fin 17.1–18.1% SL; pelvic fin 9.1– 12.0% SL.

Coloration. Described by Roberts (1989) as being creamy or pinkish white in life.

Distribution. Kapuas River basin, western Borneo ( Fig. 2 ).

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.

FIGURE 3. Mouths of Lepidocephalus. (A) L. nanensis, holotype, NIFI 4388, 72.0 mm SL, Nan River, Thailand; (B) L. pahangensis, holotype, ZRC 490, 35.8 mm SL; (C) L. spectrum, paratype, USNM 230267, 49.2 mm SL, Kalimantan. Photos by Z. Randall.

FIGURE 4. Mouths of specimens of Lepidocephalus shown in Figure 3. (A) L. nanensis, (B) L. spectrum. Although the lower lip of L. nanensis is folded more posteriorly than that of L. spectrum, it and the upper lip lack the large papillae shown on the lips of L. spectrum. Drawings by D. Lumbantobing.