Presumptive environmental effects on body shape of Aplochiton zebra (Pisces, Galaxiidae) in northern patagonian lakes.

M.E. LATTUCA; S. ORTUBAY; M.A. BATTINI; J.P. BARRIGA; V.E. CUSSAC

JOURNAL OF APPLIED ICHTHYOLOGY-ZEITSCHRIFT FUR ANGEWANDTE ICHTHYOLOGIE

Blackwell Verlag

Lugar: Berlin; Año: 2007 vol. 23 p. 25 - 33

0175-8659

Abstract The family Galaxiidae exhibits a marked tendency to morphological variation, particularly in characters related to feeding and caudal propulsion. Body shape of A. zebra from six Andean water bodies was examined and related to diet and to environmental characteristics such as transparency and predation risk. Although adults and larger juveniles showed no inter-lake dependence in their morphology, smaller juveniles (SL < 40 mm) did show differences in their eye diameter and dorsal fin length. A. zebra juveniles from Lake Puelo, where transparency showed the minimum value, have larger eyes, and those from Lake Futalaufquen, with high transparency values, have the smallest eyes. No clear relationship to predation risk was established. In Futalaufquen, Puelo and Rivadavia lakes, the relationship between Principal Components for morphology and for diet indicates that, at least in part, variation in body shape and particularly in traits related to swimming ability could be related to diet.