Male holotype of Dixonius taoi. Photo credit: Trung My Phung. — Male holotype of *Dixonius taoi*. Photo credit: Trung My Phung.

Friends, meet Dixonius taoi

November 18, 2015 by Ian Brennan

I'm pleased to introduce our newest contribution to gekkotan systematics, Dixonius taoi, a small (max 44mm SVL) island inhabitant of Vietnam. Tao's gecko, named in honor of Dr. Nguyen Thien Tao of the Vietnam National Museum of Nature in Hanoi, is restricted to Phu Quy Island, approximately 100km off the Vietnamese coast. Members of the genus Dixonius are small, nocturnal insectivores, with terminal toe-pads and the general gecko physique; making Dixonius taoi a real gecko's gecko. Recognition of this new species brings the genus up to six species, distributed across Vietnam, Laos, Cambodia, and Thailand. However, our molecular results suggest there may be additional cryptic lineages worthy of description, so keep your eyes out.

Perhaps more interesting than Dixonius alone is the relationship between Dixonius and their closest relatives Heteronotia and Nactus. Despite looking extremely similar at a quick glance, Dixonius and Heteronotia differ in one key characteristic: the presence (Dixonius) and absence (Heteronotia) of toe pads. Heteronotia, the sister taxon to Dixonius, is an Australian endemic lineage that has undergone an incredible radiation across that continent. Heteronotia binoei, which is commonly thought of as Australia's most common gecko, alone may harbour as many as 20+ species-level lineages as a result of varying chromosome ploidy levels, parthenogenetic (all female virgin-birth) populations, and severe geographic fracturing across the Australian landscape (Fujita et al., 2010). The disparity in species richness between the sister genera Dixonius and Heteronotia, and the geographic gap between them make these geckos particularly interesting to study.

Botov, A., Phung, M.T., Nguyen, T.Q., Bauer, A.M., Brennan, I.G., Ziegler, T. 2015. A new species of Dixonius (Squamata:Gekkonidae) from Phu Quy Island, Vietnam. Zootaxa 4040-1: 048-058. Download.

Fujita, M.K., McGuire, J.A., Donnellan, S.C., Moritz, C. 2010. Diversification and persistence at the arid-monsoonal interface: Australia-wide biogeography of the Bynoe's gecko (Heteronotia binoei; Gekkonidae). Evolution 64-8: 2293-2314. Download.

Saved by St. Patrick's Grace

September 22, 2015 by Ian Brennan

St. Patrick may have been able to expel all of the serpents from Ireland (not really, they just never made it there), but he missed a little lizard by the name of Zootoca vivipara, the Viviparous or Common Lizard. Although a few marine reptiles grace Ireland's shores, including Leatherback (Dermochelys coriacea), Hawksbill (Eretmochelys imbricata), Kemp's Ridley (Lepidochelys kempii), Loggerhead (Caretta caretta), and Green Sea turtles (Chelonia mydas), and the introduced European Slow-worm (Anguis fragilis) may remain hiding in the Burren of County Clare, Z.vivipara is the only native terrestrial reptile found in Ireland. Despite a broad distribution (see map below) across Ireland, this little lizard continues to be a surprising find, even for those who live, or have lived in Ireland (my dad included).

Distributional records of Z.vivipara from the Republic of Ireland and Northern Ireland. High concentrations of reports from the Wicklow Mountains in the East, Comeragh and Monavullagh Ranges in the South, and Galway Bay region in the West, highlight… — Distributional records of *Z.vivipara* from the Republic of Ireland and Northern Ireland. High concentrations of reports from the Wicklow Mountains in the East, Comeragh and Monavullagh Ranges in the South, and Galway Bay region in the West, highlight coastal heath and undisturbed habitats preferred by this species. Map credit Farren et al., 2010.

Ireland doesn't seem like a particularly hospitable place for a small lizard, but Z.vivipara manages to persist in much colder climates. The range of this species spreads from as far west as the Emerald Isle and as far east as Japan, crossing through Russia, Mongolia, and Kazakhstan. They extend down into the Iberian Peninsula, across the northern reaches of the Mediterranean, and north into the nordic countries of Sweden, Norway, and Finland. The amazing success of Z.vivipara, is likely due to their ability to frequently reinvent themselves. As an adaptation to a broad range of climes, the Viviparous lizard is both oviparous (egg laying: France, Spain, Italy, Austria, Slovenia), and viviparous (live birthing: rest of range, and some overlapping regions). Perhaps most interesting is that the switch from oviparity to viviparity has happened more than once (Surget-Groba et al., 2006).

We found Z.vivipara along the southern coast in coastal heath along the cliffs of Ballycotton. A nice sunny day brings these sluggish little guys out for a bit of basking, and wherever there was a break in the clouds, there were several Viviparous lizards piled up like solar panels. That's all for now, but maybe I'll return to talk a bit more about the biogeography of Ireland, and why its herpetofauna is so depauperate compared to the rest of the British Isles.

View from Ballycotton.

Z.vivipara found in coastal heath along the cliffs of Ballycotton.

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Sources:
Farren, A., Prodöhl, P.A., Laming, P., Reid, N. 2010. Distribution of the common lizard (Zootoca vivipara) and landscape favourability for the species in Northern Ireland. Amphibia-Reptilia 31: 387-394. Download.
Surget-Groba, Y., Heulin, B., Guillaume, C-P., Puky, M., Semenov, D., Orlova, V., Kupriyanova, L., Ghira, I., Smajda, B. 2006. Multiple origins of viviparity, or reversal from viviparity to oviparity? The European common lizard (Zootoca vivipara, Lacertidae) and the evolution of parity. Biological Journal of the Linnean Society 87: 1-11. Download.

a New Madagascan Gecko

June 30, 2015 by Ian Brennan

All the lab work from the past couple of years is finally paying off, and we've gotten another paper published in Zootaxa today. Download. We describe a new species of Blaesodactylus gecko from northern Madagascar, and estimate the phylogenetic relationships within the genus. Madagascar is an amazing place with plenty of species waiting to be discovered, so long as deforestation, overcollection, and invasive predators don't get to them first.

To balance the academic side of things, I've put together a few images of bizarre invertebrates from my recent trip to Borneo. Thanks again to Jackie and Ben for letting me use a few of their photos, find them below:

Myself, Jackie, Ben, and Adi on our way from Ba'kelalan to Merarap. photo credit: Jackie Childers — Myself, Jackie, Ben, and Adi on our way from Ba'kelalan to Merarap.
photo credit: Jackie Childers

Travels in Sarawak

June 27, 2015 by Ian Brennan

After spending the past 3.5 weeks in Sarawak, Malaysia, I'm back home in Canberra. Usually I'd be happy to be back home, but Sarawak is such an amazing place to visit, I can't say I was ready to leave. At the beginning of June, I joined up with my friends Ben and Jackie in Kuching, and we started a trip that spanned Sarawak, West to East, lowlands to highlands. I can't thank Ben enough for putting together such an awesome and successful trip, and Jackie for her fantastic photography skills. We spent as much time in the field as possible, sampling primary forest in National Parks all over, and you can find a brief storyboard of the trip here.

But maybe the best way to summarize the trip is via photos, I can't take credit for any of the photos below, so all praise is due to Jackie and Ben for their amazing photography skills. You can check out more of their work by clicking here.

diagnostic head scalation of Delma hebesa sp. nov. — diagnostic head scalation of *Delma hebesa* sp. nov.

Back from the Top End

April 28, 2015 by Ian Brennan

Just arriving back from a trip to the Top End surveying fauna in Nitmiluk National Park, and I've come home to a nice piece of news: one of the chapters of my Master's thesis has been published in Zootaxa (here). Nothing wild, but always nice to have a hand in a new species description

I'll update later this week with some more photos from my trip to Nitmiluk, but here are a few to start off.

river in the Brindabellas

Water dragon hanging in the Banks building courtyard.

sunset over Black Mountain, ANU campus.

Welcome to ANU

April 04, 2015 by Ian Brennan

Getting settled in here at the ANU, but happy to have such a great community of fellow scientists in the Evolution, Ecology & Genetics division, and particularly in the Keogh and Moritz labs. Make sure to check out the websites of other postgraduate students and friends:
Marta Vidal-Garcia
Dan Hoops
Mitzy Pepper
(Advisor) Scott Keogh
Josh Peñalba