(by g.read from niwa.co.nz)
Thu Sep 10 00:33:10 EST 2009
With 2000 specimens, some of which must be good, you should be able to make a determination, if one is indeed possible. Usually I get sent battered short ant. fragments from New Zealand harbours that I don't venture beyond placing as a Paradoneis. We also have deeper water Paradoneis - bits and pieces.
It was Andy Mackie (in Ophelia Suppl, 1991) who separated eliasoni off from lyra, and it (eliasoni) was found to be a deeper water species, with acicular posterior chaetae that are lacking in lyra. As yours are very shallow water and a different hemisphere the chances of your NZ worm (although also with acicular chaetae) being the same species is low. If that's the only known Paradoneis with acicular chaetae you probably have an unnamed taxon.
There is a published record of P. lyra for NZ - in Kirkegaard, 1996, from 610m off West Coast, South Island. P. lyra is also commonly reported from estuaries around the world, but this is likely to be only because it is the best known of the genus.
There are only 2 Paradoneis sequences in GenBank, & they not identified to a species. No help there yet. But that may be the best way these very morphologically uniform species can be worked out without agonising over natural variation, and whether my observed pointed branchiae are your blunt branchiae, etc. Words can only do so much.
Not much in the way of Paradoneis in neighbouring Antarctica is there? Not sure whether Paradoneis belgicae (Fauvel, 1936) still belongs in the genus, but haven't checked it out.
>>> On 10/09/2009 at 2:12 p.m., Brian Paavo <paavo from benthicscience.com> wrote:
> I seem to be confused. A Paradoneis is very important to some work in a
> southeast New Zealand intertidal inlet. I would normally have called it
> Paradoneis lyra (Southern 1914). I just read a paper (citation below)
> with new descriptions including a new Paradoneis eliasoni. While the
> paper is well illustrated it seems to be missing some discussion of the
> characters needed to resolve some splits (or I may be missing some
> convention). Paradoneis eliasoni appears to be described from 2
> anterior fragments and an 'almost complete' worm. I don't have a copy
> of the original Paradoneis lyra description. According to Table 3 in
> the publication, P. eliasoni has acicular neurochaetae in the far
> posterior segments. I grabbed some of our 2000+ specimens and they all
> have them. The table includes a strike rather than a question mark (no
> mention?) of these for P. lyra (Southern 1914). Both type localities
> are from the other side of the planet, P. lyra capensis (Day 1955) is
> from South Africa, but the pre-branchial notopodial lobes are present in
> our specimens, but Day may not have had specimens this large. Any thoughts?
> My diagnosis of our beast (made before seeing the paper): Conical
> prostomium slightly longer than wide, slit nuchal organs, branchiae
> start on chaetiger 4 and continue for 11-12 chaetigers [a little shorter
> than segment width), no eyes, no median antenna/scar, small notopodial
> lobes present on pre-branchial chaetigers larger in branchial chaetiger
> smaller in postbranchial chaetigers then very proporitionally large in
> extreme posterior, earliest observed forked chaetae on chaetiger 3 only
> one observed in each notopodium, posterior chaetigers with stout
> acicular chaetae (one each neuropodium) which is weakly hooked, 3
> pygidial cirri. [I didn't note the capillary numbers]
> Aguirrezabalaga, F. and Gil, J. (2009) Paraonidae (Polychaeta) from
> the Capbreton Canyon (Bay of Biscay, NE Atlantic) with the description
> of eight new species. Scientia Marina 73(4): 631-666.
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