Aphyosemion hera

biology_ecology

Ecological data (Romer, pers. comm., June 14, 1997): the biotope is similar to that of other Aphyosemion species: a shady primary forest creek (" marigot "); the water was, in summer 1996 i. e. during the long dry season, very shallow, 1 - 2 In wide and 20 cm deep, with lots of dead leaves; the water was clear, of low conductivity, slightly acid, very similar to rain water as usual for Aphyosemion (a single measurement: conductivity: 20 μS; pH = 6); at 2 p. rn., the water temperature was 21 ° C. A dozen of specimens only could be caught, whereas the other sympatric species, A. gabzmense was much more abundant. In the same locality, TIRBAK eı al. (1997) were also able to collect two other Cyprinodonts: Epiplarys sefiasciatus Gill, 1862 and E. singa (Boulanger, 1899), the typical fauna of the area between Bifoun and Lambaréné. Aquarium experience (Romer, pers. comm.): a typical non annual species which prefers dark parts of the tank, furnished with lots of plants; fairly easy to breed, despite unbalanced sex-ratios (first generation in favor of males; second in favor of females); the pair spawns on perlon mops with the standard Z-type position of Aphyosemíorı; no aggressivity displayed

A new Cyprinodont species with a uniquely-colored female, Aphyosemion hera n. sp. (Cyprinodontifonnes, Pisces), from northwestern Gabon

description

D = 11, 11, 12, 11, ll, 11, 12, 11 (mean: 11.25; S. D .. 0.43). A = 12, 12, 12, 12, 12, 12, 12, 11 (mean: 11.88; S. D .. 0.33). D / A: + 1, + 2, + 1, 0, - 1, + 1, + 1, 0 (mean: + 0.62; S. D .. 0.86). LL: 28 + 2; 28 + 4; 29 + 2; 27 + 4; 28 + 3 ç 28 + 4; 28 + 3; 29 + 3 (mean: 28.12 + 3.12; S. D.: 0.6). Predorsal scales: 14, 15, 13, 13, 14, 13, 14, 14 (mean: 13.75; S. D .. 0.7). Transversal scales (TRAV.) = 9, 9, 10, 10, 10, 9, 10, 9 (mean: 9.6; S. D.: 0.5). Circumpeduncular scales (CIR) = 15, 14, 16, 16, 17, 16, 17, 16 (mean: 15.9; S. D.: 0.9). S. L. (in mm): 31.4; 29.2; 36.7; 28.0; 25.4; 23.8; 22.4; 20.4. T. L. (in % of S. L.) = 119, 121, 125, 129, 118, 121, 120, 125 (mean: 122.3; S. D.: 3.5). P. D. (predorsal length): 62; 64, 60, 61, 63, 65, 64, 69 (mean: 63.7; S. D.: 2.8). P. A. (preanal length): 64, 61, 59, 61, 61, 63, 62, 66 (mean: 62.2; S. D.: 2.0). P. V (preventral lenth): 50, 49, 50, 53, 52, 52, 52, 53 (mean: 51.3; S. D .. 1.3). Height at Anal level: 22, 19, 21, 21, 19, 21, 19, 22 (mean: 20.4; S. D .. 1.2). Height at peduncle level: 13, 13, 15, 14, 13, 14, 13, 13 (mean: 13.4; S. D.: 0.6). Head length: 27, 28, 25, 27,27, 26, 28, 29 (mean: 27.2; S. D .. 1.2). Interorbitar = 16,

A new Cyprinodont species with a uniquely-colored female, Aphyosemion hera n. sp. (Cyprinodontifonnes, Pisces), from northwestern Gabon

discussion

DIAGNOSIS: Aphyosemiun hera is a medium-sized species with a strong sexual dimorphism and dichromatism: the female is not subdued, as usual in the genus, but Well specifically colored. The new species is besides diagnosed by the opposite insertion of the vertical fins (D / A: + 0.4, average), by the asymmetrical pattern of the vertical and caudal fins in male, by the rare, in non annual species, trilobate caudal shape in male and by the deep anal fin in female; in addition, the longitudinal dark mid-band of the young male and the female at all stages is permanent and does not depend on mood, like the one seen in some other species, especially those of the subgenus Kathetys Huber, 1977. Methods of measurements and counting have been detailed in HUBER (1992). Morphomeristic data of the first quoted eight types, the holotype first in bold (after confirmation by radiophotographs): sex: male, female, male, male, female, female, female, female.

A new Cyprinodont species with a uniquely-colored female, Aphyosemion hera n. sp. (Cyprinodontifonnes, Pisces), from northwestern Gabon

discussion

DISCUSSION The main morphorneristic characters and the colour pattern of the new species places it undoubtedly within the genus Aphyosemion among the tropical West African Cyprinodonts: average dorsal and anal fin basis (D <l 6; A <16), dorsal and anal insertion, not too far from each other (D / A <+ 8), lyre-shaped caudal fin, red pigments on sides and fins, and notably on head (the " shield "), no dark vertical bars; its 10 W meristics (D = 11.3, A: 11.9, D / A = + 0.4, on average) can only relate it to two taxa (HUBER 1996: average data): the subgenus Chromaphyosemion Radda, 1971 (D = 11.8; A = 13.6; D / A = 2.4) and the related genus Diapteron Huber and Seegers, 1977 (D = 10.7; A = 11.3; D / A = - 2.3). However the new species is distinguished from the Chromaphynsemion components by the absence of the two longitudinal mooddependant dark bands on sides of both sexes, by the shape of the vertical fins (pointed without long filaments, not trapezoid), by the shape of the caudal fin (without long filaments). It is distinguished from the Diapteron components by the shape of the vertical fins (pointed, not rounded), by the larger size (l cm larger) and by the completely different colour p

A new Cyprinodont species with a uniquely-colored female, Aphyosemion hera n. sp. (Cyprinodontifonnes, Pisces), from northwestern Gabon