Balitoropsis Smith 1945

Randall, Zachary S. & Page, Lawrence M., 2015, On the paraphyly of Homaloptera (Teleostei: Balitoridae) and description of a new genus of hillstream loaches from the Western Ghats of India, Zootaxa 3926 (1), pp. 57-86 : 73-75

Balitoropsis Smith 1945

( Figures 3 D, 4A, 5D, 11, and 12)

Balitoropsis Smith, 1945:278 . (type species: Balitoropsis bartschi Smith 1945:279 , by original designation). Gender feminine.

Remarks. The genus Balitoropsis was created for the species B. bartschi Smith 1945 and distinguished from Homaloptera (sensu lato) by having a deep preoral groove extending around the corners of the mouth and papillated lips. Kottelat & Chu (1988) noted that all members of Homaloptera (sensu lato) have a preoral groove to a varying degree and recognized Balitoropsis bartschi as a junior synonym of H. zollingeri . The papillated lips of Smith (1945) refer to unculi found on the lips of most balitorids, not the large diagnosable papillae of some balitorid genera (e.g., Balitora , Hemimyzon , Metahomaloptera ). The holotype of B. bartschi (USNM 107963) is identified as a gravid female of Homaloptera zollingeri Bleeker 1853 , as assumed by Kottelat & Chu (1988) ( Fig. 12 ).

Kottelat (1998) recognized Balitoropsis as possibly warranting recognition as a genus based on having “an elongate body, a slender caudal peduncle, carinated scales, short paired fins (pectorals usually not reaching pelvic base, pelvics not reaching anal), a dark body with a series of saddles along the back.” Balitoropsis was recognized as a genus by Kottelat (2012, 2013) and as a subgenus by Tan & Ng (2005) and Randall & Page (2012). It is recognized herein as a genus containing two species ( B. zollingeri and B. ophiolepis ).

Diagnosis. Distinguishing characters are given in Table 4 and shown in Figures 3 D, 4A, 5D, and 11. Balitoropsis is distinguished by the following combination of characters: without reddish tints on fins in life ( Fig. 3 D); dorsal-fin origin anterior to or above pelvic-fin origin; 8½ branched dorsal-fin rays; 7–9, 8 (M) branched pelvic-fin rays; forked caudal fin; keeled scales ( Fig. 4 A); 42–55 total lateral-line scales; 13–15 predorsal scales; large rostral cap; 2 thick rostral barbels in close proximity to one another; thick crescentic upper lip; fleshy pad between lateral portions of lower lip ( Fig. 5 D); anus closer to pelvic-fin insertion than to anal-fin origin.

Species included. Balitoropsis zollingeri (Bleeker 1853) and B. ophiolepis (Bleeker 1853) . Type localities for species of Balitoropsis are shown in Figure 13 .

Comparison. Balitoropsis is distinguished from Homaloptera by absence vs. presence of reddish tints on fins in life; 7–9, 8 (M) vs. 7 branched pelvic fin-rays; 13–15 vs. 20–27 predorsal scales; 42–55 vs. 59–73 total lateralline scales; crescentic vs. triangular upper lip; anus closer to pelvic-fin insertion than to anal-fin origin.

Balitoropsis is distinguished from Homalopteroides by having dorsal-fin origin anterior to or above the pelvicfin origin vs. posterior to pelvic-fin origin; 8½ vs. 6–8½, 7½ (M) branched dorsal-fin rays; anus closer to pelvic-fin insertion vs. anal-fin origin; large vs. small rostral cap; medial- and lateral-rostral barbels in close proximity to one another vs. barbels widely separated at base; thick vs. thin upper lip; presence vs. absence of fleshy pad between lateral portions of lower lip.

Balitoropsis is distinguished from Homalopterula by having dorsal-fin origin anterior to or above the pelvicfin origin vs. posterior to pelvic-fin origin; 8½ vs. 5½ and 7½, 7½ (M) branched dorsal-fin rays; 7–9, 8 (M) vs. 7 branched pelvic fin-rays; forked vs. truncated or emarginated caudal fin; keeled vs. smooth scales; 13–15 vs. 28–56 predorsal scales; 42–55 vs. 57–75 total lateral-line scales; anus closer to pelvic-fin insertion than to anal-fin origin; large vs. small rostral cap; medial- and lateral-rostral barbels in close proximity to one another vs. barbels widely separated at base; presence of fleshy pad vs. lobes between lateral portions of lower lip.

Balitoropsis is distinguished from Pseudohomaloptera by having anus closer to pelvic-fin insertion than to anal-fin origin.

Material examined. Balitoropsis zollingeri : Sumatra: BMNH 1866.5.2.53 (1); UF 161715 (3), 166094 (2), 166095 (1), 166102 (1), 166105 (1). Borneo: CAS 49331 (1); USNM 230253 (2). Thailand: USNM 107963 (Holotype of B. bartschi , examined photo); ANSP 68004 (Holotype of Homaloptera maxinae); UF 183727 (1), 235545 (1). Malaysia: CAS-SU 66420 (2), 66424 (Paratypes of Homaloptera nigra ) (2); USNM 288456 (1); UF 235547 (9), 235421 (2), 235420 (1); ZRC 2009 (Holotype of Homaloptera nigra ). B. ophiolepis : Java: RMNH 4986 (lectotype of Homaloptera ophiolepis ); BMNH 1866.5.2.49 (1). Sumatra: UF 166109 (3), 166103 (1), 166101 (1). Borneo: RMNH 28866 (1); USNM 230251 (1).

Figures

FIGURE 3. Lateral views of living (A) Homaloptera orthogoniata, not cataloged, Kalimantan, Borneo, Indonesia. Strong reddish tints on body likely breeding colors; (B) Homalopteroides smithi, UF 235740, 45.0 mm SL, Khlong Tasae, Salui Subdistrict, Chumphon, Thailand; (C) Homalopterula cf. ripleyi, not cataloged, Sumatra, Indonesia; (D) Balitoropsis zollingeri, not cataloged, Kalimantan, Borneo, Indonesia; (E) Pseudohomaloptera leonardi, UF 235735, 34.2 mm SL, Ta Pi River, Nakhon Si Thammarat, Thailand. Photos (A) & (D) by Renny Hadiaty. Photo (C) by Daniel Lumbantobing. Specimens not to scale.

FIGURE 4. Scale sizes and keel patterns of predorsal region: Large, and keeled scales, (A) Balitoropsis zollingeri, UF 166094, 52.1 mm SL; (B) Pseudohomaloptera tatereganii, RMNH 7632 (holotype), 64.6 mm SL. Large, and wart-like / keeled scales (C) Homalopteroides wassinkii, UF 183330, 43.6 mm SL. Medium, and keeled scales, (D) Homaloptera cf. ocellata, UF 161718, 64.1 mm SL. Small, and smooth scales, (E) Homalopterula ripleyi, ANSP 188908, 43.1 mm SL; (F) Ghatsa montana, CAS-SU 39871 (holotype), 46.6 mm SL. Scale bar represents 1 mm. Left side of photo is anterior.

FIGURE 5. Oral morphology of (A) Homaloptera cf. ocellata, UF 161718, 64.1 mm SL; (B) Homalopteroides wassinkii, UMMZ 155660, 46.2 mm SL; (C) Homalopterula ripleyi, ANSP 188908, 43.1 mm SL; (D) Balitoropsis zollingeri, UF 166094, 52.1 mm SL; (E) Pseudohomaloptera tatereganii, RMNH 7632 (holotype), 64.6 mm SL; (F) Ghatsa montana, (holotype) CAS- SU 39871, 46.4 mm SL. Abbreviations: CF, central furrow; FL, fleshy lobe; FP, fleshy pad; LJ, lower jaw; LL, lower lip; LRB, lateral-rostral barbel; MB, maxillary barbel; MRB, medial-rostral barbel; RC, rostral cap; UJ, upper jaw; UL, upper lip.

FIGURE 12. Dorsal, lateral, and ventral views of preserved Balitoropsis bartschi, USNM 107963 (holotype), 76.0 mm SL, Waterfall stream on Kao Chong, Trang Province, Thailand. Photos by Sandra Raredon, USNM, Ichthyology Division.

FIGURE 13. Type localities for species of Balitoropsis. Asterisk represents the type species of the genus. The type locality for B. ophiolepis shares one of the type localities for B. zollingeri (Bandung, Java).