Balitoropsis ophiolepis ( Bleeker 1853 )

Randall, Zachary S. & Riggs, Patrick A., 2015, Revision of the hillstream lizard loaches, genus Balitoropsis (Cypriniformes: Balitoridae), Zootaxa 3962 (1), pp. 206-225 : 219-223

Balitoropsis ophiolepis ( Bleeker 1853)

Slender Lizard Loach ( Figures 6 B, 9 & 11)

Homaloptera ophiolepis Bleeker 1853: 160 (type locality: Indonesia: Java: Bandong [Bandung]; lectotype: RMNH 4986; designated by Alfred 1961:35.

Balitoropsis ophiolepis . — Kottelat 2012: 46.

Remarks. In the description of H. ophiolepis Bleeker 1853 , two individuals 100 and 83 mm in total length from the type locality (Bandung, Java) were examined. Gunther (1868) assumed that one of the specimens sent to him by Bleeker was the type ( Norman and Whitehead 1984:305), and recognized it as the holotype (catalog number not listed, but it would correspond to BMNH 1866.5.2.48 [1]). However, according to Alfred (1961), Bleeker, faced with a shortage of collecting jars, would at times place specimens from several localities (including type localities) into the same jar. The specimen assumed by Gunther to be the type (BMNH 1866.5.2.48 [1], 109 mm TL) is likely one of five specimens collected by Bleeker from Lahat, Sumatra ( Bleeker 1860). Alfred (1961) examined Bleeker’s specimens at BMNH and RMNH and assigned type status to specimens that closely matched the description of H. ophiolepis Bleeker 1853 . RMNH 4986 (98 mm TL) was designated lectotype ( Fig. 9 A), and RMNH 1929 (82 mm TL) paralectotype. Both the lectotype and paralectotype are presumed to have been stored together with RMNH 4623, based on the label in Figure 9 B, which was found in RMNH 4986. RMNH 4623 consists of three individuals examined by Bleeker from Lahat, Sumatra, and are not types.

The lateral view of B. ophiolepis in Bleeker (1863 –1864, Tab 3) is labeled 4 instead of 3 ( Fig. 10 ), identifying it as Homaloptera ocellata van der Hoeven (1830) (see also Gunther 1868). Oijen and Loots (2012, figs. 13, 14) repeated the error made by Bleeker (1863 –1864) in reversing the figures of B. ophiolepis and H. ocellata .

Diagnosis. See B. zollingeri diagnosis and Table 3.

Description. Dorsal, lateral, and ventral views of B. ophiolepis are shown in Figure 11 . Measurements and meristic counts are given in Table 4. Body long and compressed (body depth 9.2–11.9% SL). Head with two rows of prominent tubercles longitudinally between nares. Eyes dorsolateral, shorter than interorbital width. Rostral cap large. Dorsal-fin origin anterior to pelvic-fin origin. Pectoral fin small reaching about midway to pelvic fin. Pelvic fin small reaching far past anus. Anus closer to pelvic-fin base than to anal-fin origin. Axillary pelvic lobe absent. Caudal fin forked with rounded lobes; lower lobe longer.

Dorsum with large keeled scales; up to 8 keels per scale. Larger individuals with hypertrophied keels ( Fig. 11 ). Scales on ventral surface posterior to anus with keels, deeply embedded between pectoral and pelvic fins. Total lateral-line scales 48–55, predorsal scales 12–15, circumpeduncular scales 13–14. Scales above and below lateral line 6–7/4–6, respectively. Scales below lateral line to pelvic-fin origin 5–6. Modal fin-ray counts (variation given in Table 4): dorsal iii, 8½; anal ii, 5½; pectoral iv, 10, i; pelvic ii, 8; total caudal 17.

MORPHOMETRICS Lectotype Bleekerspecimen Non-types

n=7

RMNH 4986 BMNH 1866.5.2.48 USNM 230251 Adult Range Adult

Mean±%SD

Standard Length 79.4 93.6 34.7 60.5-101.2 Length n/a 109.4 43.2 78.2-127.4 of Standard Length

Lateral head length 18.8 19.7 21.2 17.7-20.4 19.3±1.3 Body depth 9.2 10.2 9.7 10.5-11.9 11.2±0.8 Body width 11.3 14.5 11.1 12.2-14.7 13.0±1.2 Distance from pelvic fin to anal fin 29.6 29.8 29.3 29.5-31.2 30.3±0.7 Dorsal-fin base length 13.9 13.4 14.8 13.2-15.0 14.0±0.7 Dorsa-fin length 17.8 19.8 23.5 19.9-22.0 21.3±1.2 Pectoral-fin length 19.4 19.3 19.6 18.6-20.2 19.4±0.6 Pelvic-fin length 17.0 17.4 18.5 17.0-18.4 17.8±0.6 Anal-fin length n/a 12.2 13.4 12.0-14.6 12.8±0.9 Predorsal length 42.6 45.1 44.9 43.5-45.4 44.7±0.7 Caudal-peduncle length 15.5 18.5 20.4 18.2-19.9 19.2±0.9 Caudal-peducle depth 4.0 4.8 4.6 4.7-5.1 4.8±0.2 of Head Length

width 67.8 65.8 67.9 70.7-76.5 72.3±2.9 depth 33.6 43.4 40.8 43.8-49.5 45.1±2.8 Snout length 56.4 54.9 59.9 55.7-58.2 57.6±1.4 Length of orbit 20.8 16.5 21.7 15.7-19.5 18.1±2.1 Interorbital width 34.2 33.7 35.3 33.0-38.7 36.0±1.8 Pectoral-fin length 103.4 98.3 92.4 92.9-112.8 101.3±7.4 of Interorbital Width

Length of oribit 60.8 48.9 61.5 42.6-59.2 50.4±7.2

…Continue on next page Mouth ( Fig. 6 B) inferior, lips with tiny unculi, continuous around corners of mouth. Upper lip crenulated, distal-lateral extension of lower lip common. Fleshy pad present between lateral halves of lower lip. Rostral and post-labial grooves present. Two pairs of rostral barbels, one pair of maxillary barbels. Barbels with tiny unculi, rostral barbels in close proximity to each other.

The smallest individual of B. ophiolepis ( Fig. 11 B) differs in measurements and meristic counts from the larger individuals ( Table 4). Major differences are: 55 vs. 48–52 total lateral-line scales, scales on ventral surface anterior to pelvic fin absent vs. present, scales with 1 vs. up to 8 keels.

Color in 70% ethanol ( Fig. 11 ): Dorsally light cream-brown with dark brown stippling. Six dark brown saddles usually present. First saddle between supraoccipital and dorsal fin; 2nd saddle at dorsal-fin origin; 3rd saddle at end of dorsal fin; 4th saddle anterior to anal-fin origin; 5th saddle at end of anal-fin; 6th saddle immediately anterior to caudal-fin base. One individual has an extra saddle between saddles 5 and 6. Light brown mid-dorsal stripe extends from supraocciptal to posterior saddles. Large blotches sometimes surround anterior saddles. Two large blotches extend posteriorly from each side of the supraoccipital and often join the post-orbital bar. Large blotch on head between post-orbital bars and nares, at the nares and opercle. Tip of snout with two lateral blotches divided by cream-colored bar.

Lateral-line covered with large blotches, usually positioned between saddles, decreasing in size posteriorly. Venter cream-colored and lightly stippled. Undersurface of head lightly stippled.

Number of dark brown bands on fins: dorsal 4–5; pectoral 4–5; pelvic 3–5; anal 2–3; caudal 4–6. Dark brown bands at upper lobe of caudal fin of some individuals faint. Dorsal, pectoral, and anal fins with black base. The smallest individual (USNM 230251, 34.7 mm SL) differs slightly in color having a less pronounced 6th dorsal saddle at caudal-fin base; 2 bands on dorsal, pectoral, pelvic, caudal (?) (lower lobe missing) fins; 1 band on anal fin.

Distribution and Ecological Notes. No recent collections are known from the type locality of Bandung, Java, and the species has likely been extirpated from this highly developed area. The species is known to occur in Java: West Java (Tjitaroem basin); Sumatra: Sumatera Selatan (Musi basin) and Lampung (Tulangbawang basin); Borneo: Kalimantan Barat (Kapuas basin) ( Fig. 8 ). The species has been collected from rocky riffles with swift currents.

Material examined. Balitoropsis ophiolepis : Java: RMNH 4986 (lectotype of Homaloptera ophiolepis ); BMNH 1866.5.2.48 (Bleeker specimen) (1). Sumatra: UF 166109 (3), 166103 (1), 166101 (1). Borneo: RMNH 28866 (1); USNM 230251 (1).

Figures

FIGURE 6. Oral morphology of (A) Balitoropsis zollingeri, UF 166094, 52.1 mm SL; Sumatera Selatan, Sumatra, (B) B. ophiolepis, UF 166109, 101.2 mm SL; Lampung, Sumatra. Scale bar 3 mm.

FIGURE 8. Distribution of Balitoropsis. Locality in Cambodia from Rainboth, et al. (2012).

FIGURE 9. (A) Dorsal, lateral, and ventral views of lectotype of Homaloptera ophiolepis, RMNH 4986, 79.4 mm SL; Bandong (Bandung), Java. (B) Label from RMNH 4986.

FIGURE 10. Original drawings from Bleeker (1863 – 1864). (A) Balitoropsis zollingeri, (B) B. ophiolepis. Positions modified from original publication. Designation of lateral view of B. ophiolepis as “ Fig. 4 ” is an error.

FIGURE 11. Dorsal, lateral, and ventral views of preserved Homaloptera ophiolepis. (A) UF 166109, 101.2 mm SL; Lampung, Sumatra. (B) USNM 230251, 34.7 mm SL; Kalimantan Barat, Borneo.