Alestiini

Among Alestidae, the Alestiini comprises the moderate to large-sized species of the genera Alestes, Brycinus and Bryconaethiops. To date, few detailed studies allow us to propose a stable classification of Alestidae, and here we follow the traditional division that essentially considers all alestid species that do not belong to Petersiini as Alestiini (see Alestide). As summarized in table below, except for a relatively large size, most Alestiini have very few common characters and almost certainly this tribe is not monophyletic.

Characteristics of the Alestiini.

Alestiini: eye with an adipose eyelid (left) or without eyelid (right).

Alestiini: fronto-parietal fontanel present (left) or absent (closed) (right).

While the genera Alestes and Bryconaethiops do seem to represent monophyletic groups (Murray & Stewart, 2002), this is not the case for the genus Brycinus. Based on morphological features, Paugy (1986) distinguished three groups within Brycinus. On the basis of osteological characters, Murray & Stewart (2002) recognised only two groups and proposed a new genus for some species. Subsequent to this writing, two studies have independently discovered evidence supporting non-monophyly of Brycinus and tribal re-assignment of a subset of the species. The results of both Zanata & Vari (2005) and Calcagnoto et al. (2005) placed the species of the 'longipinnis group' within a clade inclusive of taxa traditionally recognized as the Petersiini, with the former study advocating resurrection of the genus Bryconalestes Hoedeman, 1951 for that species assemblage. For the time being, pending the outcome of future phylogenetic studies, we retain here the genus Brycinus and distinguish three groups:

Key to genera

1   Premaxillary teeth triserial........................................................................ ..........Bryconaethiops

     Premaxillary teeth biserial..........................................................................................................2

2   An adipose eyelid covering at least a part of eye; a well developped fronto-parietal fontanel....Alestes

     No adipose eyelid covering eye; fronto-parietal fontanel narrow or absent............................Brycinus

Bibliography