The family Alestidae (Ostariophysi, Characiformes): a phylogenetic analysis of a trans-Atlantic clade

Abstract

The overall most parsimonious hypothesis of relationships based on 200 characters indicates that the Alestidae is the closest relative of Chalceus, a genus previously assigned to the Neotropical Characidae. Chalceus is shifted into the Alestidae, which becomes the only trans‐Atlantic family level group within the Characiformes. Various previously proposed suprageneric assemblages within the Alestidae (e.g. Petersiini) failed to delimit monophyletic groups under the intrafamilial phylogenetic analysis. The evaluation of fossil alestids within the context of the phylogeny indicates that the ancestors of Alestes, Arnoldichthys, Brycinus, Bryconaethiops and Hydrocynus evolved prior to the early Eocene (Cuisian of Upper Ypresian), 49–54.8 million years ago, with the fossil Alestoides most closely related to Alestes. The phylogenetic information further indicates a minimum age of 90–112 million years for the Alestidae. Contrary to previous hypotheses, the fossil African Sindacharax was found to be most similar to the clade including the alestid genus Bryconaethiops rather than most closely related to the South American subfamily Serrasalminae. Evaluation of the fossil Mahengecharax carrolli fails to support its hypothesized placement as the sister group to all Recent members of the Alestidae. Two separate episodes of miniaturization and one episode of gigantism occurred within the evolution of the Alestidae. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 145, 1−144. No claim to original US government works.

Reproductive morphology of Brittanichthys axelrodi (Teleostei: Characidae), a miniature inseminating fish from South America

“…Although most characid fishes are endemic to South America, some of their close relatives in the family Alestidae, order Characiformes, occur in both Africa and South America (Zanata and Vari, 2005), leading biogeographers to hypothesize that the most recent common ancestor of all characiforms inhabited the supercontinent of Gondwanaland before its tectonic plates began to drift apart about 120 million years ago (Lundberg, 1993;Ortí, 1997;Zanata and Vari, 2005).…”

A new stem fossil characid (Teleostei: Ostariophysi) from the Eocene-Oligocene of southeastern Brazil

“…In the counts of fin rays, lower case Roman numerals indicate unbranched rays, and Arabic numerals indicate branched rays. Nomenclature mostly follows Weitzman (1962), with some modifications suggested by subsequent authors (Fink & Fink, 1981;1996;Zanata &Vari, 2005): mesethmoid instead of ethmoid, vomer instead of prevomer, epioccipital instead of epiotic, endopterygoid instead of mesopterygoid.…”

Two new species of Odontostilbe historically hidden under O. microcephala (Characiformes: Cheirodontinae)

“…First unbranched dorsal-fin ray less that half-length of second, following branched rays gradually decreasing in size posteriorly. Presence of small ossification associated with first proximal dorsal-fin radial (character 124, described by Zanata, Vari, 2005). First unbranched ray of dorsalfin inserted in first pterygiophore and last two branched rays inserted in tenth pterygiophore.…”

“…Dorsal fin with 10(5) pterygiophores. Presence of small ossification associated with first proximal dorsal-fin radial (character 124, described by Zanata, Vari, 2005). Proximal radial of first pterygiophore of dorsal fin posterior to neural spine of ninth precaudal vertebra.…”