Austrofundulus Myers 1932

Tomas Hrbek, Donald C. Taphorn & Jamie E. Thomerson, 2005, Molecular phylogeny of Austrofundulus Myers (Cyprinodontiformes: Rivulidae), with revision of the genus and the description of four new species., Zootaxa 825, pp. 1-39 : 12-13

Austrofundulus Myers 1932

Austrofundulus Myers 1932 : 159-162 (original description, type species: A. transilis Myers , by original designation, based on single specimen). Hoedeman 1961: 89-91 (based on head scale patterns, Austrofundulus put in separate subfamily from Rachovia ). Weitzman and Wourms 1967: 89-100 (generic characters discussed, validity of Austrofundulus , Rachovia and Pterolebias is doubted). Vaz-Ferreira and Sierra de Soriano 1972: 38-40 (attempt to distinguish Austrofundulus and Rachovia based on neuromast and lateral pore patterns, caudal and pelvic-fin morphology). Thomerson 1979: (comments on generic name). Elder Jr. et al. 1991: (karyotypes, comments on generic names). Costa 1990: (based primarily on osteological and meristic characters, Austrofundulus placed into synonymy of Rachovia ). Costa 1998: ( Austrofundulus revalidated but without explanation). Huber 1999: (morphometric relationships to other rivulin genera). Hrbek and Larson 1999: (phylogeny based on mitochondrial DNA data). Murphy et al. 1999: (phylogeny based on mitochondrial DNA data).

Diagnosis. Austrofundulus are Neotropical, northern South American, annual rivulid fishes that are distinguished from all new world rivulids except Rachovia in having at least the basal 45% of the caudal fin scaled. They differ from the closely related genus Rachovia (see Fig. 4) in having: more dorsal rays, usually 14 or more (range 12-18) vs. 13 or fewer (range 9-14); a longer dorsal fin base, more than 16% SL (12-25%) vs. less than 16% (10-18%); more lateral scales, usually 32 or more (28-38) vs. 32 or fewer (27-33); and more transverse scales, usually 11 or more (9-16) vs. usually 10 or less (8-11). Many males of R. brevis and R. maculipinnis have a dark blotch around white spots on the dorsal fin, a pattern never seen in Austrofundulus , which never has white spots on the dorsal fin of males. The anal and genital papillae are usually heavily pigmented in Austrofundulus but only lightly pigmented or unpigmented in Rachovia and other new world rivulids from northern South America.

Austrofundulus is distinguished from Terranatos (see Fig. 5) in having: shorter fins, the dorsal fin less than 55% SL (range 23-47%) in males, and less than 40% SL (range 22 -40%) in females, versus more than 55% (55-124%) and more than 37% (37-47%) in males and females of Terranatos , respectively; caudal fin scaled for more than one third of its length vs. unscaled except at base; female without extensions of caudal fin rays vs. filamentous rays on the dorsal and ventral margins; maximum standard length more than 30 mm vs. less than 30 mm SL; anal actinosts articulated with hemal spines rather than ribs.