New cyprinid genus

A new genus of cyprinids, Hongshuia was described in China recently to accommodate two new species, Hongshuia paoli and H. banmo, which have been described from the Pearl River system in Guangxi Province in South China.

Source: Practical Fishkeeping.

The real Corydoras aeneus

Ian Fuller has an interesting article about Corydoras aeneus online at Practical Fishkeeping. The species was first described by Gill from fish collected in Trinidad - consequently, Trinidadian populations of C. aeneus are most likely to be true representatives of that species. Given their proximity, Venezuelan C. aeneus should be closest to the Trinidadian form. However, Fuller points out that there are three distinct Venezuelan forms: the typical form, C. aeneus 'Black' and a third form that Fuller considers a distinct species, C. venezuelanus Ihering, 1911. There are several other varieties that Fuller believes should be maintained as separate species. Some of these have been described as distinct species in the past.

Fuller finds it dubious that such different forms are the same species, especially since they are found in such far-flung locations as Trinidad, Argentina and Peru, in river systems that have been unconnected for millions of years. I suppose a good molecular study might be able to shed some light on the relationship within this group - at the very least, whether they form a monophyletic group or whether other species are nested within the group. If they are sister taxa, then the matter of whether they are the same or different comes down to the opinions of lumpers and splitters.

Dedicated amateurs

The February issue of Tropical Fish Hobbyist includes a detailed article about recent changes in the systematics of Central American cichlids - what used to be the genus Cichlasoma. The author, Wayne Leibel, delves into the some pretty heavy-duty systematics papers and produces a very readable - and very detailed - synopsis of what's going on. For someone who appears to have no formal training in the field, he handles it amazingly well.

This is one of those things that fascinates me. While amateur botanists (and, for that matter, an awful lot of professional plant scientists and ecologists) tend to treat nomenclatural changes with disdain, fish keepers appear different - many seem happy to keep up with the "latest" names. Part of it may come from the fact that fish keepers are often on the leading edge of discovery of new species - newly discovered loricariid and corydorinid catfish are assigned L and C numbers while the hobbyists wait on systemtists to describe the species. But I suppose tropical fish keepers experience tropical diversity in a way that few other people in the temperature zone ever do. And it's a short step from "I want to know the name of my fish" to "I want to know the current name for my fish".