Austrofundulus leoni, Tomas Hrbek, Donald C. Taphorn & Jamie E. Thomerson, 2005

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 : 25-28

Austrofundulus leoni new species

Figures 12 and 13

Holotype. FMNH 108225 (ex FMNH 85268). Adult male (28.2 mm) collected in a small temporary pond approximately 5 km from the junction of the road to Machiques between Macoa and Río Yasa; collected by J. Thomerson and F. Mago on 26 June 1972.

Paratypes. FMNH 85268, ten additional specimens collected with the holotype. FMNH 85724, twenty six specimens Venezuela, Zulia collected in a temporary pond 5 km north of Campo Mara, 25 June 1972, J. E. Thomerson. MCNG 33448, six specimens Venezuela, Zulia, Libertad, Caño antes de la Hacienda Las Mercedes, 22 July 1974, C. Lilyestrom, D. Spiers, V. Sabril, DISCA74-128. MCNG 39145, one specimen Venezuela, Zulia, Perijá, Saliendo de la poblaciôn de Sartaneja, 10° 6' 35” N, 72° 19' 7” W, O. Leon. MCNG 39146, six specimens, same data as 39145. MCNG 39147, four specimens Venezuela, Zulia, Préstamo cerca de la Hacienda el Japon, 30 June 1978, D. Taphorn, E. Sutton.

Diagnosis. This species is distinguished from all species of Austrofundulus by strong reddish-brownish background body color observed in all sexually mature males. Relative to other species, the caudal peduncle is slender. The caudal fin is also large and slender with long extensions.

Description. Males have a reddish-brown colored background in the dorsal fin with several curved rows of dark brown spots. Basal spots are large, often joining into irregular or oblong flecks. The dorsal often has long fin ray extensions. The dorsal fin of females is unpatterned, with clear or light gray background. The background color of the males’ caudal fin is reddish, with grayish overtones towards the posterior section of the fin. There are numerous indistinct dull gray spots randomly dispersed on the caudal fin. The distal edge has a weak blue-black terminal edge. Both the dorsal and the ventral edge of the caudal fin extend to form a long “lyre-tail”. Females have a light grayish translucent caudal fin. The anal fin of males is patterned similarly to the dorsal fin. The background color is brownreddish with a few large indistinct gray flecks in the basal half of the anal fin. The large gray flecks coalesce and become darker to form a blue-black distal margin. The base of the anal fin is creamy white, grading into this same color on the belly. The anal fin often has a long extension. The anal fin of females is clear or light gray, with a few faint basal spots. The pectoral fins of males are uniformly translucent brownish-red with a grayish edge. The pelvic fins of males are similar to the pattern found on the anal fin. The background color is brownish-red with a few large dull gray spots in the basal portion of the fin, although in some males the spots are absent. The base of the pelvic fin is almost white, and blends with the color of the belly. Females have translucent, light gray pectoral and pelvic fins. The basic background color is brownish-red with gray overtones. Few dull light gray to almost white spots are present in the posterior two thirds of the body, while the anterior one third of the body has several dark brown to black colored spots. Just above, and across the opercle, the spots are arranged into several diagonal rows. The ventrum is light gray to almost white, without spots, while the dorsum is darker than the rest of the body. In females, the sides are light brown to light gray colored. The body is not spotted. As in males, the abdomen of females is lighter than the rest of the body, while the dorsum is darker. An indistinct black bar passes through the eye of both sexes, passing obliquely through the eye onto the head posteriorly above and anteriorly below the eye. The iris is silver. The upper portion of the head is dark gray, the lower light gray to cream. In females the head is predominantly gray or olive dorsally, and lighter ventrally. A few iridescent golden scales are present on the males’ opercle, which has an overall yellowish tone. For meristics and morphometrics see Table 7. Austrofundulus leoni attains up to 29.4 mm. SL with a mean length of 26.0 mm SL. Females reach up to 33.6 mm. SL with a mean length of 25.9 mm SL.

Etymology. From Latin leo (lion) for its large size and majestic nature, and for the family León Mata who has been instrumental to conducting research in the Maracaibo basin.

Distribution. This species is distributed in the western and southwestern lowlands of the Lake Maracaibo basin. In the north it is replaced by A. guajira which occurs in Venezuela only near the border with Colombia and across the Guajira peninsula. Specimens collected from the drainage of the Río Limón have all proved to be A. leoni .