Homalopteroides Fowler 1905

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 : 67-70

Homalopteroides Fowler 1905

( Figures 3 B, 4C, 5B, 7)

Homalopteroides Fowler, 1905:476 . (Type species: Homaloptera wassinkii Bleeker 1853 , by original designation; see Randall & Page, 2012:335 fixed type species as H. wassinkii , under Code art. 70.3.1). Gender masculine. Chopraia Prashad & Mukerji, 1929:188 (Type species: Chopraia rupicola Prashad & Mukerji, 1929 , by original designation). Gender feminine.

Remarks. Homalopteroides rupicola was originally designated as the type species of Chopraia ( Prashad & Mukerji 1929) . Chopraia was distinguished from other balitorines by “shape of the head, the situation and better development of the eyes, the branchial openings and the fins ( Prashad & Mukerji 1929).” Since these characters are shared with species of Homalopteroides , we treat Chopraia as a junior synonym of Homalopteroides ( Randall & Page 2012) .

Diagnosis. Distinguishing characters are given in Table 4 and shown in Figures 3 B, 4C, 5B and 7. Homalopteroides is distinguished by the following combination of characters: without reddish tints on fins ( Fig. 3 B) in life, dorsal-fin origin posterior to pelvic-fin origin; forked caudal fin; 6–8½, 7½ (M) branched dorsal-fin rays; wart-like/keeled scales ( Fig. 4 C), 14–25 predorsal scales; 33–52 total lateral-line scales; anus closer to analfin origin than to pelvic-fin insertion; no adipose keel on caudal peduncle; small rostral cap; 2 thin rostral barbels, widely separated from one another; thin crescentic upper lip; no fleshy pad or lobes between lateral portions of lower lip ( Fig. 5 B); and presence of a central furrow at isthmus.

Species included. Homalopteroides wassinkii (Bleeker 1853) , H. modestus (Vinciguerra 1890) , H. rupicola ( Prashad & Mukerji 1929) , H. smithi ( Hora 1932) , H. stephensoni ( Hora 1932) , H. weberi ( Hora 1932) , H. tweediei (Herre 1940) , H. indochinensis ( Silas 1953) , H. nebulosus ( Alfred 1969) , H. yuwonoi ( Kottelat 1998) , and H. avii Randall & Page 2014 . The type localities for species of Homalopteroides are shown in Figure 8 .

Comparison. Homalopteroides is distinguished from Homaloptera by absence vs. presence of reddish tints on fins in life; dorsal-fin origin posterior vs. anterior to pelvic-fin origin; 6–8½, 7½ (M) vs. 7–8½, 8½ (M) branched dorsal-fin rays; 33–52 vs. 59–73 total lateral-line scales; small vs. large rostral cap; medial- and lateral-rostral barbels widely separated from one another at base vs. barbels in close proximity to one another; crescentic rather than triangular upper lip; thin vs. thick upper lip; presence vs. absence of a central furrow at the isthmus; absence vs. presence of fleshy pad between lateral portions of lower lip.

Homalopteroides is distinguished from Homalopterula by having forked vs. truncated or emarginated caudal fin; wart-like/keeled vs. smooth scales; 14–25 vs. 28–56 predorsal scales; 33–52 vs. 57–75 total lateral-line scales; absence vs. presence of adipose keel on caudal peduncle; thin vs. thick upper lip; absence vs. presence of fleshy lobes between lateral portions of lower lip.

Homalopteroides is distinguished from Balitoropsis and Pseudohomaloptera by having dorsal-fin origin posterior vs. anterior to or above the pelvic-fin origin; 6–8½, 7½ (M) vs. 7–9½, 8½ (M) branched dorsal-fin rays; small vs. large rostral cap; medial- and lateral-rostral barbels widely separated from one another at base vs. barbels in close proximity to one another; thin vs. thick upper lip; absence vs. presence of pad between lateral portions of lower lip. It is further distinguished from Balitoropsis by having the anus closer to anal-fin origin than to pelvic-fin insertion.

Material examined. Homalopteroides wassinkii : Java: RMNH 4987 (lectotype of Homaloptera wassinkii ), 1934 (paralectotypes of Homaloptera wassinkii ) (2), 4627 (2); BMNH 1866.5.2.52 (1); ZMA 103.206 (2); UMMZ 155660 (1); MNHN 3122 (syntype of Balitora ocellata ). Sumatra: UF 161619 (7). H. modestus : Thailand: ANSP 179826 (5); NIFI 4517 (1), 3786 (1), 4514 (1); ROM 51147 (2); UF 172926 (1), 173067 (1), 176377 (10), 176408 (2), 176438 (8), 176454 (4), 176544 (1), 176557 (8), 181080 (5), 181160 (9), 181141 (1); ZRC 53385 (1), 53386 (1), 41272 (4). Myanmar: ZRC 22889 (1); BMNH 1893.2.16.50 (paralectotype of Helgia modesta ); ZMA 100.982 (paralectotype of Helgia modesta ). H. rupicola : Myanmar: CAS-SU 28726 (paratype of Chopraia rupicola ); CAS 231681 (2), 231726 (3), 231835 (1), 61338 (1); USNM 378433 (3); ZRC 43569 (2). H. smithi : Thailand USNM 109821 (syntypes of Homaloptera smithi ) (5); ANSP 76852 (1), 76851 (3); BMNH 1934.12.18.34 (1); UF 183330 (3), 183411 (2), 183915 (1). H. stephensoni: Borneo : RMNH 7633 (holotype of Homaloptera stephensoni ); USNM 393671 (3). H. weberi : East Malaysia: BMNH 1895.7.2.81 (syntypes of Homaloptera weberi ) (7); ZMA 100990 (syntype of Homaloptera weberi ). H. tweediei : Malaysia: BMNH 1938.12.1.132 (paratype of Homaloptera tweediei ); CAS-SU 33012 (holotype of Homaloptera tweediei ), 33013 (paratype of Homaloptera tweediei ) (2). H. indochinensis : Vietnam?: BMNH 1933.8.19.50 (holotype). H. nebulosus : Malaysia: BMNH 1967.11.15.15 (paratype of Homaloptera nebulosa ); CAS-SU 66428 (paratype of Homaloptera nebulosa ); ZRC 1759 (paratype of Homaloptera nebulosa ); ZRC 2020 (holotype of Homaloptera nebulosa ); UF 235748 (6). H. yuwonoi : East Malaysia: MZB 5938 (holotype of Homaloptera yuwonoi ). H. avii : East Malaysia: USNM 323875 (holotype of Homalopteroides avii ), 323878 (paratype of Homalopteroides avii ), USNM 323879 (paratypes of Homalopteroides avii ) (2); UF 185293 (paratype of Homalopteroides avii ).

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 8. Type localities for species of Homalopteroides. Asterisk represents the type species of the genus.