Molecular phylogeny of East African Synodontis

Post by **Silurus** » 08 Sep 2006, 09:02

Koblmuller S, C Sturmbauer, E Verheyen, A Meyer, W Salzburger, 2006. Mitochondrial phylogeny and phylogeography of East African squeaker catfishes (Siluriformes : Synodontis). BMC Evolutionary Biology 6, Art. 49.

Abstract

Background: Squeaker catfishes (Pisces, Mochokidae, Synodontis) are widely distributed throughout Africa and inhabit a biogeographic range similar to that of the exceptionally diverse cichlid fishes, including the three East African Great Lakes and their surrounding rivers. Since squeaker catfishes also prefer the same types of habitats as many of the cichlid species, we hypothesized that the East African Synodontis species provide an excellent model group for comparative evolutionary and phylogeographic analyses.

Results: Our analyses reveal the existence of six major lineages of Synodontis in East Africa that diversified about 20 MYA from a Central and/ or West African ancestor. The six lineages show a clear geographic patterning. Two lineages are endemic to Lake Tanganyika (plus one non-endemic representative), and these are the only two Synodontis lineages that diversified further into a small array of species. One of these species is the cuckoo catfish (S. multipunctatus), a unique brood parasite of mouthbrooding haplochromine cichlids, which seems to have evolved in parallel with the radiation of its cichlid host lineage, the Tropheini. We also detect an accelerated rate of molecular evolution in S. multipunctatus, which might be the consequence of co-evolutionary dynamics.

Conclusion: We conclude that the ancestral lineage of today's East African squeaker catfish fauna has colonized the area before the Great Lakes have formed. This ancestor diversified rapidly into at least six lineages that inhabit lakes and rivers in East Africa. Lake Tanganyika is the only lake harboring a small species flock of squeaker catfishes.

sidguppy · Post by **sidguppy** » 08 Sep 2006, 16:04

I'm very very very very very much interested in this article, HH!

a big THANK YOU if you can get me a PDF-copy or something.

lfinley58 · Post by **lfinley58** » 08 Sep 2006, 17:07

Sidguppy, and all - I think you, or anyone interested in Lake Tanganyikan Synodontis, will enjoy the paper. Once you get past the "heavy" molecular stuff there are lots of interesting tidbits. The authors divide the species into two clades. The first consists of S. multipunctatus and S. granulosus (but with a caveat on the latter species). There is also mention of a new species (but no details) in the clade number two which consists of S. petricola, S. polli and S. dhonti. It will be interesting to see what this new species is and where it fits in relation to the fishes that we see imported. One described species, S. tanganyicae, was not included in the study.

I have submitted an overview of the paper for my TFH column.

The paper is available on-line. If you search "BMC Evolutionary Biology" and Synodontis it should pop up. Sorry that I am lacking in the cut and paste techniques. I am trying to get it down.

Lee

sidguppy · Post by **sidguppy** » 09 Sep 2006, 08:26

And a big THANK YOU to HH
after I checked out my mailbox this morning