I can off hand think of 2 others that should be looked at. Bearing in mind that
I don't consider myself as any kind of taxonomist, but it's always good to have
things looked at. A lot of what is below is from some notes, memory & also
photos.
Firstly the so-called Brown Thornbill Acanthiza pusilla of Tasmania (as opposed
to the Tasmanian Thornbill Acanthiza ewingi, which is more obviously a good
species), I do believe shows some genetic similarities with the Inland
Thornbill, rather than the SE subspecies of Brown Thornbill. I did detect some
differences between Tas Brown Thonbills and those of the mainland when I was
there last there in 2010. This included: a stouter, larger bill; paler
freckling on the forehead with less of a rufous tinge than the mainland ssp;
more greyish brown tinge overall on the upperparts, less richly olive-brown
upperparts; also perhaps less buffy on the flanks & undertail (not so certain
of this one). It would be also useful to investigate things like undertail
pattern. Many of these characters sound more on the Inland Thornbill side,
rather than Brown. If the Tas A. pusilla is more closely related genetically to
Inland Thornbills, then either all 3 should be split into distinct species,
or all lumped (since Brown Thornbill & Inland almost certainly interbreed in
some areas, for example I've seen some possible hybrids in the Kamarooka mallee
region of Bendigo & perhaps the Little Desert). I definitely think this one
deserves a good look.
The other is the Tas Grey Fantail. Given the great variation within Grey
Fantails in Aust., this one is probably a bit more tenuous, but it shares
something with the Boobook Owls. The Tas ssp albiscapa (which migrates to the
Aust mainland in large numbers in Autumn, Winter & Spring is darker almost
sooty grey compared to the mainland birds (subspecies alisteri), which are more
medium grey. Sometimes because of wear & age this is difficult to see in the
field, but these 2 subspecies can nearly always be separated by their undertail
patterns. Tas birds have only the very fringes of the outer tail feather edged
white, whereas mainland birds have white extending further into the feather,
about a centimetre. The reason this bird has something in common with Boobooks
is that in NZ they have a fantail (now regarded as a full species) which is
darker, although the very white tail pattern suggests that this bird is
probably correctly regarded as a full species now. Also in the mountai
ns of NE Qld there is a similar resident subspecies of Grey Fantail, which is
dark above (even darker than Tas birds!) & has narrow white fringes to the
outer tail feathers. In many ways this bird is similar to Tas albiscapa. Also
Boobooks have a small dark representative in NE Qld, which is the Red Boobook.
Whether this is all convergence, or relict populations needs to be tested with
genetics. But it is interesting from a taxanomic point of view, that there are
these similarities between Tas, NZ & SE Qld, in both Grey Fantail & Boobooks &
it needs to be ascertained whether they all have a common ancestor, or have
become as they are in isolation. Certainly worth questioning.
Look forward to the feedback-Kevin Bartram
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