Journal Article
Systematics and biogeography of Sternarchellini (Gymnotiformes: Apteronotidae): Diversification of electric fishes in large Amazonian rivers
Ivanyisky, S.J. and Albert, J.S.
Record Number:
4611
Year:
2014
Journal:
Neotropical Ichthyology
Pages:
565-584
Volume:
12
Abstract:
The Sternarchellini (Gymnotiformes, Apteronotidae) is a clade of 10 electric fish species that inhabit deep river channels of the
Amazon and Orinoco basins, attain moderate adult body sizes (15-50 cm TL), and have a predatory life style. Here we trace the
evolutionary origin and diversification of Sternarchellini using standard phylogenetic and biogeographic procedures and a
dataset of 70 morphological characters. The main results are: 1) the genus Sternarchella includes both species currently
assigned to the genus Magosternarchus; and 2) neither of the multi-species assemblages of Sternarchellini in the Amazon and
Orinoco basins are monophyletic. Historical biogeographic analysis suggests that sternarchelline evolution was linked to the
large-scale river capture event that formed the modern Amazon and Orinoco basins, i.e. the Late Miocene rise of the Vaupes
structural arch and concomitant breaching of the Purus structural arch. This event is hypothesized to have contributed to
formation of the modern sternarchelline species, and to the formation of the modern basin-wide sternarchelline species
assemblages. The results indicate that cladogenesis (speciation) and anagenesis (adaptive evolution) were decoupled processes
in the evolution of Sternarchellini.
Times Cited:
3