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New rodent family



Okay, so it's not dinosaurian, or even fossil, but I feel a discovery this
significant deserves a mention :-):

Paulina D. Jenkins, C. William Kilpatrick, Mark F. Robinson, Robert J.
Timmins. 2005 (dated 2004). Morphological and molecular investigations of a
new family, genus and species of rodent (Mammalia: Rodentia: Hystricognatha)
from Lao PDR. Systematics and Biodiversity 2 (4): 419-454.

"During biodiversity surveys in Khammouan Province, Lao Peoples Democratic
Republic, specimens of an unknown species of hystricognathous rodent were
discovered in local markets being sold for food; local hunters explaining
that these rock rats were trapped in the nearby limestone karst. These
specimens are described here on the basis of their unique combination of
external and craniodental features as members of a new family, genus and
species, using comparative morphological and molecular data. Phylogenetic
analyses of morphological data and of 12S rRNA and cytochrome b are
presented on selected taxa from all suborders of Rodentia. The results of
the molecular and morphological analyses are compared and provide the basis
for a discussion of relationships of the new taxon within the Rodentia and
Hystricognatha.

The disjunct distribution of hystricognaths is recognised as problematic,
with most families occurring in the main distributional area of South
America, several others in Africa and only one family distributed in Africa
and Asia. The presence of an additional hystricognath family in Southeast
Asia poses interesting questions and consideration is given to the way in
which this new taxon fits into the theories of the biogeographical and
evolutionary history of other hystricognaths. Features of possible
ecomorphological significance are briefly discussed, such as the apparent
adaptations to a rock dwelling existence evident in various features of the
external morphology and comparisons are made to the morphology of other
known saxicolous rodents."

    _Laonastes aenigmamus_ is the name of the beastie, placed in its own
family Laonastidae. Morphological phylogenetic analysis places _Laonastes_
basal to other hystricognaths except _Pedetes_ and Ctenodactylidae, while
molecular analysis nests it among other (mostly African) Old World
hystricognaths, such as _Petromus_, _Thryonomys_, _Heterocephalus_ and
_Hystrix_. Hystricidae are the only other hystricognath family found in
Asia.
    I can't recall when was the last time a recent family of mammals was
described, but I'm willing to bet it was some time ago. The part of the
world that had hidden from us until recently such marvels as _Pseudoryx_ and
_Megamuntiacus_ (though odds now seem in favour of _Pseudonovibos_ not being
a valid taxon) continues to surprise...

    Ka kite ano,

        Christopher Taylor