Friday, 27 May 2016

Tidying up the tenrecs

Dobson's shrew tenrec (Nesogale dobsoni)
Photo (C) Peter J. Stephenson
A fresh phylogenetic analysis (here) based on sequence data from all living tenrecs and one otter shrew allows a re-evaluation of tenrec systematics.

The study confirmed the web-footed tenrec (Limnogale mergulus) is nested in the genus Microgale and should henceforth be referred to as M. mergulus.

However, the authors also suggest resurrecting the generic name Nesogale for two species hitherto placed in Microgale. These are Dobson's shrew tenrec (N. dobsoni) and Talazaci's shrew tenrec (N. talazaci). Support for this included a 4-codon deletion shared only by these two species and a separate 9-codon deletion lacking in these species but found in the remaining Microgale. They concluded that this lineage had diverged from other shrew tenrecs in the Miocene.


Villous area of the placenta of Dobson's shrew
tenrec (Nesogale dobsoni) stained for cytokeratin (brown)
We included N. talazaci and N. dobsoni in our study of placentation in shrew tenrecs (here). As in Microgale and Oryzorictes there was both a central labyrinth and a more peripheral villous area. We did not notice any differences that would set Nesogale apart.

No comments:

Post a Comment