>>Mmmmmm. Molecules and Invasions...interesting - though a bit confusing to one that is not part of the molecular illuminati, but definitely interesting. I am a little surprised at the apparent relatively recent separation of the two Oxyuranus scutellatus members...

Join the club - my first thought was that this was a sampling mix-up, so everything was redone - but the results stayed the same, also with additional samples.

> I think you should go over your data again or apply some other bit of molecular gymnastics because I have seen both scutellatus and canni - and I considered them to be parapatric species - and if my suspicion is correct, then I think they may have differentiated more than your present data indicates.

Quite possibly. Before we got those sequences back, I had rather assumed I would end writing about evidence in favour of canni being a separate species.

All the mtDNA sequences really tell us is that there has clearly been recent and extensive gene flow between the two. It is of course possible that the Aussie and NG populations have been in situ much longer, but that introgressive hybridization swamped out the mtDNA haplotypes of one of the two populations, while other alleles were retained - we can't tell, at least not from our current sampling, which is also why we did not sink canni formally. Other molecular methods (e.g., AFLPs) would certainly be of interest also.

> You alluded to the genus Oxyuranus also including microlepidotus as most others seem to believe, but I feel this should be revisited to - Parademansia has two quite different populations of microlepidotus within it, one in south-western New South Wales (Yes, the species is NOT EXTINCT within this State as is commonly believed) and the other in south-western Queensland and north-eastern South Australia.

I look forward to your package with samples from these localities

> Sure, they have some similarities, but I still believe that their similarity to Pseudonaja may indicate more than just convergence.

Basically, O. microlepidotus retains a more ancestral morphology, which would have been more similar to Pseudonaja, whereas O. scutelatus evolved its present much more derived morphology later. We do have sequence data for O. microlepidotus, and they show it to be the closest relative of O. scutellatus - in fact that relationship is one of the most strongly corroborated phylogenetic relationships among Aussie elapids, from a numebr of different marker systems. Obviously, whether one chooses to recognise Parademansia as a separate genus or not based on morphological differentiation is, at the end of the day, a purely personal and arbitrary decision.

> As for "Pseudechis" well as I have long maintained, the traditional use of this genus for that assemblage of species makes no ecological or morphological sense at all. I still hold the view that Pseudechis contains only the porphyriacus populations. The australis members (except the weigelli complex) should be placed within Cannia. The weigelli complex are so distinct that Ross Wellington and I almost placed them in a separate genus back when we described weigelli in 1987, but decided not to as "Cannia" seemed like an easier pill for others to swallow at the time (yes, we were being conservative!). Hoser's "Pailsus" may in fact be an available generic name for the weigelli complex, but this will have to be for others to determine with more certainty than I can.

For Pseudechis, we went with nomenclatural stability. I agree, P. porphyriacus is very distinct indeed genetically from the other species of the genus, but since our data did not provide clear evidence that it is NOT monophyletic, since there is some morphological evidence indicating monophyly of all Pseudechis, and since others are working on this, we left it in the traditional way. Nomenclature is, in the first instance, an informaion retrieval system, and nomenclatural changes are disruptive, if not for us taxonomists then for everyone else (just like I get p*ssed off when my local supermarket changes all the shelves around and it taes me twice as long to do my shopping). Consequently, when changes are proposed, I regard the onus of proof as resting on those proposing the change. Our data did not clearly show Pseudechis to be broken, so we didn't fix it. If later work does show Pseudechis to be non-monophyletc, ten I will be happy to cherr Cannia along for the other species of the genus. Heck, I could even countenance recognising Panacedechis for guttatus, colletti and papuanus if Pseudechis is going to be split at all. However, I don't see any reason to place the various weigeli, pailsi, rossignolii etc. into a separate genus from Cannia - they are similar enough to australis (which is why we regard them as different species), and the evidence for the monophyly of "Pailsus" is practically non-existent in any case.

Cheers,

Wolfgang
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