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This is a very "lousy"post, but bear with me...
As for previous phylogenetic analyses, the paper (Smith et al., 2011)
finds a sister clade relationship between the louse clades
Rhyncophthirina and Anoplura. The origins of both groups are shown
going back to the Cretaceous.
The Anoplura (sucking lice) radiated after the K-Pg extinction,
consistent with the evolutionary diversification of their mammal hosts
at the same time - today there are around 500 species of sucking lice.
By contrast, the Rhyncophthirina includes only a single extant genus
_Haematomyzus_, which contains three species of lice that are
parasites on warthogs and elephants.
_Haematomyzus_ feeds on blood, but it doesn't suck the blood from its
host: the strong, chewing mouthparts attached to the end of the long
proboscis are used to break through the host's skin, causing pools of
blood to form, which the louse then feeds on. The long, drill-like
mouthparts of these particular lice are specialized for penetrating
the thick skin of their hosts. The legs of _Haematomyzus_ are slender
and unable to cling to hairs - unlike the sucking lice (Anoplura),
which have stout legs ending in strong claws for grasping hair or fur.
So extant memers of Rhyncophthirina are ectoparasites of large,
thick-skinned, sparsely-haired mammals - and these lice have
adaptations to suit. But if the Rhyncophthirina have been around as
long as the Anoplura... what were their hosts during the Cretaceous?
On Thu, Apr 7, 2011 at 3:16 AM, Ian Paulsen <email@example.com> wrote:
> HI ALL:
> Ian Paulsen
> Bainbridge Island, WA, USA
> Visit my BIRDBOOKER REPORT blog here:
- From: Ian Paulsen <firstname.lastname@example.org>