Updates on Anolis lividus from Montserrat’s Volcanic Exclusion Zone

Image of the 1995 eruption of the Soufrière Hills volcano on Montserrat.

Image of the 1995 eruption of the Soufrière Hills volcano on Montserrat. Photo from Wikipedia.

On July 18, 1995 something big happened on a tiny little island in the Lesser Antilles. The Soufrière Hills volcano erupted on Montserrat, an island only about 40 square miles in size that is nestled between Nevis, Antigua, and Guadeloupe. The eruption buried the (then) capital city of Plymouth under several meters of ash and pyroclastic flow. More than a dozen nearby towns were also destroyed. Residents in the south of the island had to evacuate, leaving their homes and land behind. Since then, Montserrat has experienced considerable volcanic activity. In fact, when I was on the island in 2010, I witnessed a major dome collapse, an event that was magnificent to see on the ground, and was even observable from space. I’ve spent some time trying to find Anolis lividus, Montserrat’s endemic anole, across the island, with particular focus on finding it in the south, where volcanic impact has been greatest. Montserrat is basically divided in half by the Belham River Valley, a barren bed of ash that effectively separates the habitable north of the island from the more inhospitable south. I’ve spent many hours in the south of the island searching for A. lividus over a few years. In my experience, the lizards were not abundant (if to be found at all) south of the Belham. Granted, access to this region was very restricted, so I didn’t get to spend a whole lot of time there, but I only ever saw two lizards (a mating pair) on a tree in Richmond Hill, a part of the southern half that’s in Zone C. Towns in Zone C are close to the Belham River Valley and are occasionally opened up for visitors when the volcano has been quiet for a while. Currently, Zone C has ‘unrestricted access’, meaning people can visit day and night without an escort. There is also a relatively unexplored portion of Montserrat southeast of the volcano (the South Soufrière Hills) that has plenty of good habitat and is isolated by the rest of the island by the volcano. There have been a few focused expeditions to that part of the island (for example, to collect individuals of Leptodactylus fallax, the ‘mountain chicken’ frog, for a breeding program), but I haven’t been able to get there.

My interest in A. lividus lay mostly in understanding how recolonization works. Can the lizards cross the Belham River Valley, or is it too hot and inhospitable? As access to inner zones increases, will humans mediate transport into the south of the island? If they get there, will they persist? Although I haven’t been to the island in a few years, I remain very interested in the system. I recently received news on Anolis lividus from Nicolas Tirard, a new resident on the island. He had visited Zone C (which is currently open to daytime visitors) and found an individual of A. lividus. Nicolas informed me that he spotted the lizard (a male) on the terrace of an abandoned home in Richmond Hill, which is the same neighborhood where I found lizards almost six years earlier. Nicolas spent about 30 minutes canvassing this area and only found one lizard. For anyone with experience finding anoles in the Caribbean, particularly in the Lesser Antilles, we know that they are generally much more abundant than that. So I would reckon that lizards in Zone C are probably still pretty scant. I wonder if the lizard Nicolas did find descended from previous inhabitants in that area (for example, from the mating pair I observed earlier), or whether there have been more recent dispersal events. He went back on another occasion to St. George’s Hill, which he says is more densely forested than Richmond Hill, and saw three lizards there. When I visited St. George’s Hill a few years ago it was pretty barren, so clearly the habitat is recovering there.

Anolis lividus from Richmond Hill, Montserrat.

Anolis lividus from Richmond Hill, Montserrat. Photo by Nicolas Tirard.

I asked Nicolas if he thought that humans were transporting the lizards (accidentally or otherwise) to Zone C through increased transit. Nicolas reckons the lizards can get there on their own right now. He says, “I don’t think it is a human-mediated recolonization, even if there is traffic going back and forth, because the vegetation has grown again in the Belham river, and it is probable that anole can now cross it by themselves.” The finding that the Belham is vegetated is interesting – during my visits there it was a hot, barren bed of ash. The only herps I saw there were enterprising iguanas, boldly basking on piles of hot ash. I also saw an iguana on the roof of a house once in Richmond Hill. As the exclusion zone becomes more accessible, I hope that people will try to find A. lividus (and other organisms) there and, hopefully, share their observations with the Anole Annals.

Nicholas shares his observations on his blog. He has also seen a blind snake (Typhlops) and several iguanas in the exclusion zone. Check out his blog for more.

Another image of the male Anolis lividus spotted in Richmond Hill.

Another image of the male Anolis lividus spotted in Richmond Hill. Photo by Nicolas Tirard.

A Treasure Trove of Fossil Geckos

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amber geckosWho knew there were so many fossil geckoes? In the first review of fossil geckodom in more than three decades, Juan Daza, Aaron Bauer, and Eric Snively examine 28 fossil geckos, providing new insights into whether the specimens can be confidently attributed to taxa. Some times, they can placed into extant genera, other times, especially for the older ones, it’s hard to say for sure just where the belong.

If nothing else, the fossils are cool and sometimes quite old, the most ancient, Cretaceogecko, dating back to the early Cretaceous.

This paper was part of a special of the Anatomical Record published last year, “New Advances In Morphology and Evolution of Living and Extinct Squamates,” which was previously discussed in these pages.

Here’s the abstract:

Gekkota is often interpreted as sister to all remaining squamates, exclusive of dibamids, or as sister to Autarchoglossa. It is the only diverse lineage of primarily nocturnal lizards and includes some of the smallest amniotes. The skeleton of geckos has often been interpreted as paedomorphic and/or “primitive” but these lizards also display a wide range of structural specializations of the postcranium, including modifications associated with both scansorial locomotion and limb reduction. Although the concept of “Gekkota” has been variously applied by different authors, we here apply a rigorous apomorphy based definition, recent advances in gekkotan morphology and phylogenetics, and diverse comparative material to provide a comprehensive assessment of 28 known pre-Quaternary geckos, updating the last such review, published three decades ago. Fossils evaluated include both sedimentary fossils and amber-embedded specimens. Known Cretaceous geckos are exclusively Asian and exhibit character combinations not seen in any living forms. Cenozoic gekkotans derive from sites around the world, although Europe is especially well represented. Paleogene geckos are largely known from disarticulated remains and show similarities to Sphaerodactylidae and Diplodactylidae, although resemblances may be plesiomorphic in some cases. Many Neogene gekkotans are referable to living families or even genera, but their geographic occurrences are often extralimital to those of modern groups, as is consistent with paleoclimatic conditions. The phylogenetic placement of fossil gekkotans has important repercussions for timetree calibration, but at present only a small number of fossils can be confidently assigned to even family level groupings, limiting their utility in this regard.

More Examples of Different Dewlap Colors in Males and Females

dewlap dimorphism

In a recent post, we discussed the description of two new Costa Rican anoles, but didn’t draw attention to the fact that all members of the A. pachypus species complex exhibit dewlap dichromatism, with the dewlaps of males and females differing within a species. Shown here are differences in A. tropidolepis (top) and A. pachypus (bottom). The images on the right are females and the left and center are males.

In a previous post, we discussed this phenomenon, but its explanation still escapes us. Interestingly, it occurs almost exclusively in mainland anoles.

Which Anole Is That in the Addams Family Dollhouse?

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anole skeletonJoe Martinez of the Museum of Comparative Zoology writes in: “I was recently contacted by Samantha Grantham, the collections manager of the Wenham Museum in Wenham Massachusetts, who would appreciate learning the identification of a lizard skeleton that resides in the Coffin Room of their Addams Family dollhouse. The dollhouse was constructed locally, presumably with artifacts that were readily available.

It appears to be an anole and Anolis carolinensis would have been available through the pet trade at that time. Anolis sagrei may have begun showing up in the pet trade as well by then. Can anyone give an authoritative identification?”

And want to learn more about the Addams Family Dollhouse? There’s a whole blog devoted to it!

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New Book on the Anoles of Honduras

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johnsmeyersiMcCranie and Köhler have just published an authoritative account of the 39 species of Honduran anoles. Rich in detail and thorough in coverage, this volume will be of interest to anyone interested in neotropical herpetology.

Harvard University Press’s description says it all: Caribbean members of this group have been intensively studied and have become a model system for the study of ecology, evolution, and biogeography, but knowledge of the anoles of Central and South America has lagged behind. In this landmark volume, veteran herpetologists James R. McCranie and Gunther Köhler take a step toward rectifying this shortcoming by providing a detailed account of the rich anole fauna of Honduras. Generously illustrated with 157 photos and drawings, The Anoles of Honduras includes information on the evolutionary relationships, natural history, distribution, and conservation of all 39 Honduran anole species. The work is the result of decades of study both in the field and in museums and is the first synthetic discussion of the complete anole fauna of any Central or South American country. Each species is described in great detail with locality maps. Bilingual (English and Spanish), extensively illustrated identification keys are also included.

Distribution maps are provided for all species.

Distribution maps are provided for all species.

Like all publications of the Bulletin of the MCZ and Breviora, the book is freely available as a pdf on the journal’s website. But a pdf just doesn’t look right on a bookshelf, not to mention getting soggy in the field. For those who really  want to get the most out of this volume, why not consider purchasing it from Harvard University Press for only $24.95 (not bad for a 280 page volume jam-packed with color photos!)? And it’s even cheaper on Amazon (currently $20.48).

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A Lizard Whodunnit: Field Work Is Not Always about Answering the Question You Set Out to Study

On her own blog, Ambika Kamath explains that field work is often about surprises and unexpected mysteries. Check out A Macabre Start to My Time in Florida.

Help Identify Anole from Guyana

Photo by Thadaigh Baggallay

Thadaigh Baggallay writes: “I took this picture in Kaieteur National Park, Guyana. Anolis chrysolepis perhaps?”

Looks to me like whichever chrysolepis-type anole occurs in Guyana. Exactly a year ago today, we had a post on a new field guide to Guyanan herps by Cole et al. which probably would help. According to that guide, I believe the species would be A. planiceps. Any thoughts any one?

 

Neat Ditty About a Thermoregulating Lizard

Screen Shot 2015-02-22 at 10.26.03 PMHarry Bird and the Rubber Wellies is described as a nomadic folk band, and they’re based out of Dublin, Ireland and Bilbao, in the Basque Country of Spain. Maybe it’s the cold rainy climes of both those places that inspired these musicians to create a wistful song about a tropical lizard basking on a palm tree. It’s a catchy tune, so check it out.

Here are some of the lyrics from the song:

“When Sun come out / Out come the lizard / Lazing around / And a’flicking her tail/ When Sun go home / Home go the lizard / Till the Sun come out again.”

“See the way she slide / My, what a lizard! / She got so many beautiful scales / She the way she shine.”

“Oh she’s catching flies / That greedy lizard / Her long sticky tongue / Doesn’t make any sound / She gets pomegranate / Out of the cupboard / That’s the way to wash them down.”

 

Video of Anolis pentaprion Displaying

Little is known about the Central American twig anole, but it does have a beautiful dewlap! In recent years, what used to be known as A. pentaprion has been split into a large number of species, the most recently described of which is A. triumphalis. (Editor’s note: Gunther Kohler points out that this is one of the newly named species, A. charlesmyersi).

Here’s the backstory from the videographer who posted this on Youtube: Greetings Casa Alta Vista, Costa Rica. That video was shot about 15 feet above ground, on the guava wood handrail that goes up my stairs. Our house is a rustic style “pole” house, constructed from plantation grown gmelina and teak woods. We are located about 2 miles inland of the shores of Golfo Dulce , Costa Rica, at about 600 feet elev. in a mostly second growth seasonally dry rainforest. Dry season from Dec to April, then usually 300 inches of rain , a lot of which is in September-October usually. We are across the gulf from Corcovado National Park . Maybe 15 miles as the toucan flies. The area around the house was pasture up until about 20 years ago, but now pretty lush with second growth. Fairly undeveloped, and there is some primary growth surrounding us down in the “quebradas” or streams that are all around here. Down there we have stream anoles, and lots of snakes and critters. Saw a bushmaster down there once . Yikes. We also see slender anoles (I think) but they aren’t very “brown” and the yellow spot on the dewlap isn’t as prominent as the picture in my book . We also sometimes see the dry forest anole, which seems to trade off the territory of my deck railing system with the lichen anoles. We see green anoles down on some of the fruit trees we have planted as well. Amazing creatures all, they don’t seem fearful of us, and maintain eye contact . And will bite of course if they are provoked and can catch hold of you. I once had a full grown basilisk lizard that I was rescuing from some dogs bite me nicely on the hand. We have really a lot of all kinds of wildlife here. The birding is great, and we have a large troop of mono titi’s (squirrel monkeys) that occasionally traverse our back deck, peek in the windows, and move on to eat guabo beans in the trees surrounding our house. We’re built about 4 meters off the ground, not a treehouse , but kind of up in the trees .
My camera is new, and I will be posting other animal videos soon. And will try to get more anole videos.

Editor’s Update, 2/23/2015:

Here’s another clip of the same animal:

Anolis huilae Displaying

 

Photo by Cristian Castro Morales

Photo by Cristian Castro Morales

AA reader Cristian Castro Morales has sent in this photograph of the little known Anolis huilae. He says: Male of Anolis huilae display their dewlap to ward off a possible predator or rival from his perch. This species is reported in Colombia in the departaments of Huila and Tolima.

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