Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional del Comahue, Quintral 1250, San Carlos de Bariloche, 8400 Río Negro, Argentina.
J Fish Biol. 2013 Nov;83(5):1321-33. doi: 10.1111/jfb.12233. Epub 2013 Oct 11.
Variation in the vertebral number of the puyen grande Galaxias platei was examined for specimens from 22 localities that span the entire distribution range of the species (from 40° to 55° S). The mean vertebral number (NMW ) increases towards high latitudes, i.e. Jordan's rule is applicable to this species. Owing to the wide geographic variation of the species, not only in latitude but also in altitude, the most explicative variable for NMW was mean winter air temperature, showing negative dependence. Morphological data suggest that the increment in vertebral number lies in the pre-pelvic region of the trunk and in the caudal region, but not in the segment between pelvic-fin insertion and the origin of the anal fin. As these alterations in body shape have important consequences for hydrodynamics and swimming performance, vertebral number variation in G. platei also holds implications for both individual and population fitness.
对分布于南纬 40°至 55°之间的 22 个地点的大比目鱼 Galaxias platei 标本的椎骨数量变化进行了研究。平均椎骨数（NMW）随着纬度的升高而增加，即约旦规则适用于该物种。由于该物种在纬度和海拔上都有广泛的地理变异，对 NMW 最具解释性的变量是冬季平均空气温度，呈负相关。形态学数据表明，椎骨数量的增加位于躯干的前骨盆区和尾部，但不在骨盆鳍插入和臀鳍起点之间的节段。由于这些体型变化对水动力和游泳性能有重要影响，大比目鱼 G. platei 的椎骨数量变化也对个体和种群的适应性具有重要意义。
