The following photos were sent to me by a colleague, and were taken during a trip to Costa Rica during December, 2011- January, 2012. We’ll start with the crocodiles of Rio Grande de Tarcoles, which are an attraction for both Costa Rican and foreign tourists, who gather at the highway bridge to see the many large crocodiles gathered there. I was told on one of my visits there that there used to be some sort of slaughterhouse or rendering plant, and that the offal was dumped in the river, which initially attracted the crocodiles. People now feed them, although I think this is officially discouraged.
She also saw crocodiles on a trip to Tortuguero.
Also at Tortuguero was this heron, a widespread species which is also found in the southeastern US, breeding at least as far north as New York.
A visit to the area of Fortuna revealed a couple of species of mammals. This is a normally colored Mantled Howler Monkey,
while this one is “blonde”; I’ve never seen a howler of this color myself.
There were also bats.
And last but not least, because they are practically honorary cats, a squirrel from Volcan Poas.
For the midpoint of Amphibian Week, Chris Petersen of Department of Defense Partners in Amphibian and Reptile Conservation sent me these amphibian facts.
Characteristics of Amphibians:
· Include frogs and toads, salamanders and caecilians (approximately 8,300 species worldwide)
· All are vertebrates (have a backbone)
· Are ectothermic (meaning they rely on external sources from the surrounding environment to maintain their body temperature)
· Most live part of their life in water and part on land (although there are many exceptions)
· Most have moist glandular skin through which they can respire (breathe) to various extents (some exclusively so, but most also through lungs or gills)
· Lay unshelled (jelly-like) eggs in moist to wet environments
· Most go through a process called metamorphosis to develop from a water-living life stage to a land-living stage
I then headed out to Greenquist Pond here at UW-Parkside to see what amphibians were about. You’ll recall that Chorus Frogs and American Toads have been calling on campus, but I hadn’t seen them at this pond. Here’s what I found.
I walked around three sides of the pond, and heard or briefly saw several Rana jump into the water, many emitting a little “yelp” as they dove in. I think both Green Frogs (Rana clamitans) and Bullfrogs (Rana catesbeiana) make that noise, so I wasn’t sure of the species. All were smallish, except for one that was bigger, but could have been either a large Green or a medium Bullfrog in size. I was heading back, reconciled to failure, when I spotted this medium-sized Bullfrog on the bank, which didn’t spook. I was able to get pretty close to get this shot, and even was using sticks to bend shadowing leaves out of the way, but it stayed put.
The Green Frogs and American Toads I showed in earlier Amphibian Week 2021 posts were also from this pond, but I’ve not seen them at the pond yet this year. (Some of the frogs today may have been Green Frogs.)
There were also turtles, so I’ll cheat a bit (they are reptiles, of course) and throw them in here. There were four five Painted Turtles (Chrysemys picta),
plus this Red-eared Slider (Trachemys scripta elegans), with another two Painted Turtles behind.
There were a total of four five Painted Turtles, all with the slider in this corner of the pond. The slider is the most popular turtle in the pet trade, and is not native to Wisconsin. Although we find them not infrequently, they all seem to be released or escaped– they don’t seem to breed up here, even though they can survive the winters. (I had my own “Spot the …” moment– I didn’t see the further back Painted Turtle in the above photo until I’d posted it here!)
Today’s diverse photos come from reader, anthropologist, and photographer Tony Eales from Queensland. You can enlarge his photos by clicking on them, and his captions are indented.
To answer the call for the readers’ wildlife segment and boost the tank I present some of the other critters and one plant that I photographed on my road trip to the tropical north of my state of Queensland.
First is Cosmophasis micarioides, a small jumping spider found throughout eastern Queensland, and highly variable. The mature males all look the same, with stripes of iridescent aquamarine, white and black; indeed all the male Cosmophasis in Australia are variations on that theme. The females are more colourful with patches of red, green, sometimes purple and golden brown. This one is a juvenile, which in the tropical north are the most colourful of all. In South East Asian species these spiders are often colourful wasp mimics. That may be what the juveniles are going for here, but I can’t think of a wasp model offhand.
Ethmostigmus rubripes is the Australian giant centipede. It’s not as big as the giant centipedes I encountered in Borneo, but they’re still very impressive beasts. This one was probably a shade over 160mm. It was very fast and darted about looking to hide from my light. I can imagine it would deliver a very painful bite if one attempted to handle it.
The Peppermint Stick insect (Megacrania batesii) likes to eat the leaves of the many Pandanus trees in north Qeensland. I had seen pictures of them and have always been struck by their odd colouration. They look more like a plastic toy version of green than one that would really help with camouflage.
I’m sad that I didn’t get a good shot of these prehistoric looking Orange-footed Scrub Fowl (Megapodius reinwardt). They were common enough around the gardens of Port Douglas where we were staying. From a distance you could watch them scratching the leaf litter, but they would slip off into the dense plants when approached.
It was great to see these relatively large Southern Spotted Velvet-Geckos (Oedura tryoni) around Eungella National Park. During my lifetime, my home town of Brisbane has been overrun by introduced Asian House Geckos (Hemidactylus frenatus,) displacing the shyer natives and patrolling every outdoor light. It’s hard to describe the happiness of seeing a gecko running around the walls and noticing that it wasn’t one of those intruders.
Real treat for me was to see my first Emperor Gum Moth (Opodiphthera eucalypti). Technically, I have seen the caterpillars, which are spectacular in their own way, but this was my first adult attracted to the lights at a lonely highway rest stop.
I kind of bombed out on my bucket list spiders for this trip, but one long-desired species that I did photograph was the Australian Lichen Huntsman (Pandercetes gracilis). The camouflage is so good I was only able to see it because of the eyeshine. Night hunting Wolf Spiders and Huntsmans have very strong reflective eyeshine, making them easy to find at light with a torch.
It was only because I had stopped to look at the Huntsman that I noticed this other master of camouflage nearby. This is the Northern Spiny Rainforest Katydid (Phricta spinosa). I was on a night walk with my wife and a friend, and this friend and I were exclaiming about how crazy this Katydid looked and my wife, who was standing with her face only a foot or so away from it, was saying “Where? What are you looking at?” When I pointed it out, she yelped and literally jumped back as it was hidden right under her nose.
I also found several of these strange Theridula sp., one of the comb-footed spiders. The photo suffered from my inability to see what I was focussed on because the humidity of the rainforest fogged up my camera viewfinder and my glasses all the time. I didn’t get a single shot that wasn’t focused on the leaf background instead of the spider.
Lastly, the classic shot tourist shot of the Daintree Rainforest includes these beautiful North Queensland Fan Palms (Licuala ramsayi). Sunlight shining through their leaves graces nearly every piece of tourism advertising for world heritage rainforest.
Today we have a contribution from physicist and origami master Robert Lang, presenting some photos called “Altadena: Squirrel Noms Edition” (Altadena, California is where he lives). His captions and descriptions are indented, and you can enlarge the photos by clicking on them:
Most of these photos were taken from my office out the window above my desk.
Naturally we need to start with a kitty. Our first pic is a Bobcat (Lynx rufus), a species I get regular visitation from, though more often at night than daytime. As you can see here, the meadow outside my studio is starting to come back to life, which brings out the ground squirrels and rabbits that keep the bobcats coming.
I live and work in Altadena, on the northern boundary of the freeway-and-housing metropolis of Los Angeles. Because the mountains rise so abruptly, the boundary between civilization and wilderness is pretty sharp, and so we get a lot of wildlife along the edges, both big and small. The Western Fence Lizard(Sceloporus occidentalis) is one of the smaller ones.
One of my favorite visitors is the Acorn Woodpecker (Melanerpes formicivorus). They’re distinctive and chatty, and the locals seem to have forgiven me for letting Edison replace the old telephone pole last year that had become on of their granaries over the years.
I rarely see the Gray Fox (Urocyon cinereoargenteus) during the day, but one is a common nighttime visitor who gets snapped by an IR camera I have set. Here’s video.
The Western Gray Squirrels (Sciurus griseus) regularly come down from the trees to root around for seeds and such. This time of year, there’s lots of empty acorn caps, but not many acorns left (last year was a bumper crop).
A different kind of squirrel is the California Ground Squirrel (Otospermophilus beecheyi), which, though superficially similar to the grays can be distinguished by a tinge of brown and speckling in the fur and a not nearly as fluffy tail. (As the name suggests, they live in burrows, not trees.) This morning I saw a behavior I’ve never seen before: one was climbing around on a patch of Prickly Pear Cactus (Opuntia sp.), which must have hurt! Or else he climbed very carefully.
What could be so attractive to induce one to brave the glochids (the short, incredibly nasty little spines that grow in the areoles)? Turns out he was eating the cochineal insects (Dactylopius coccus)—which produce and live under the white, waxy tufts that you see around the areoles.
He went from pad to pad, cleaning them off. I’d never known that squirrels were cochineal predators, but this explained why they slowly disappeared from the cactus over the summer. I’m sure the cactus appreciated the squirrels’ cleanings.
In this last photo, you can see some of the waxy tufts around the squirrel’s mouth and I think I see one of the cochineal insects stuck on the end of a whisker—they’re tiny dark red dots (and are the source of Red Dye #4, also know as carmine, and commonly used in foods and cosmetics).
In this last photo, he has his eyes closed, and I see him as savoring the flavor of this delicacy that made it worth the trip and the spines. (I imagine Jerry having the same expression after a particularly juicy slab of brisket.)
Today we have a contribution from Tony Eales of Queensland. His notes are indented, and you can enlarge his photos by clicking on them.
My wife and I did a road trip back up to tropical North Queensland to stay at Port Douglas and visit various places of natural beauty including the 40-million-year-old World Heritage Daintree Rainforest and the remnant isolated rainforest in the Clarke Range with its high degree of species endemism.
While bugs and spiders are my thing, I must say, though, that the vertebrates took a front seat on this trip with some truly fantastic sightings of mammals, birds and reptiles unique to these places, alongside some very interesting arthropods.
We were very lucky to come across two cassowaries (Casuarius casuarius) on our first day in north Queensland. We saw a third on our last day as well. These are wonderful birds to see, particularly because we were in the car rather than on foot. I’m not sure I’d like to come face to face with a cassowary without some barrier between it and me. They’re known as the most dangerous bird in the world and have killed at least two people that I am aware of. There are numerous videos of cassowary attacks on YouTube, this one is particularly alarming.
The absolute highlight of the trip and one of my best experiences with wildlife was finding this small family of Bennett’s Tree-kangaroos (Dendrolagus bennettianus) while on a night walk in the Daintree. These are a very rare animal: their ranges is only 70 km north-south and 50 km east-west. They are very quiet and stay high in the canopy. My wife noticed the red eyeshine but they were so far up in the dark it was difficult to determine at first what we were looking at. It was a long frustrating struggle to coax my camera that was set up for insects to focus on and capture an image of these animals. I am informed that this is the first photographic evidence of them living in small family groups. An unforgettable experience.
It was a good night for arthropods as well. I found this predatory katydid, the Pink-jawed Katydid (Emeraldagraecia munggarifrons), formally described only in 2012. It was just chilling out on a handrail waiting for something tasty to wander along.
Daytime was amazing too in the Daintree. We went to the Daintree Discovery Centre which had walking trails with lots of informative signage and displays. The best was a tower that took you up into the canopy. Right beside the tower was a huge Black Bean tree (Castanospermum australe) and while looking at the leaves I noticed this giant colourful bug, a Yellow-horned Giant Stinkbug (Oncomeris flavicornis). The bug was the size of a matchbox but only has a tiny head which is apparently typical of this family.
While leaning out over the edge of the railing to try and photograph the bug I noticed this large beautiful longicorn beetle Rosenbergia drouini. As soon as I put the picture up on Facebook, I was inundated with friend requests from beetle collectors asking if I had collected the specimen. This was apparently a very rare find and is not in many collections.
After our time up in the north we took our time coming home and spent a bit of time at Eungella National Park up in the Clarke Range. This rainforest is large but isolated and is recognised as a centre of endemism. I was able to find two of the key endemics while there. The Eungella Spiny Katydid (Phricta zwicka) and the Eungella Leaf-tailed Gecko (Phyllurus nepthys).
JAC: Look at that camouflage!
Also, on a night walk in the rainforest I snapped a photo of a pretty moth Ecnomophlebia argyrospila. It turns out that this is the only known live photo that the Australian moth experts I talked to have seen and it’s only known from a single specimen collected in 1927.
Two other notable endemics I photographed on the trip home were a land snail Pedinogyra cania that is restricted to a single locality called Cania Gorge and the cute Mareeba Rock-Wallaby (Petrogale mareeba) that lives only in the granite hills around the north Queensland town of Mareeba.
Today’s post features subterranean wildlife, but not of the fossorial kind. It has wildlife you can see in the New York subway, but it’s not “pizza rat” or his lateravatars: it’s the wildlife art of the 8th Avenue local (B and C trains) station at 81st-Museum of Natural History.
We’ll start with my favorite, what is clearly a hatchling Green Anole (Anolis carolinensis; the proportions, especially the large head, show it’s a hatchling). The Museum clearly had significant input on the designs, although it’s not always clear if the artists followed exact specifications for species identification, but in this case I’m confident. Important work on anoles was done by former curators James Oliver and G.K. Noble, and the latter’s anole work was mostly on this species.
We’ll continue with the rest of the lizards. The next is clearly a monitor lizard, and it’s bulk indicates it’s a Komodo Dragon (Varanus komodoensis).
Next up is a basilisk or Jesus Christ lizard (Basiliscus sp.), famed for their bipedal locomotion, which includes the ability to skitter Christ-like across the surface of bodies of water for short distances. This mosaic introduces an element common to the artwork, the depiction of extinct forms as grayed “ghost” silhouettes, often paired with an extant form. In this case we have two bipedal diapsids: the basilisk and the theropod dinosaur Deinonychus (note the ‘terrible claw’ and short snout); the latter is about life size, but the basilisk is greater than life size. (This is an estimate, but I think the white tiles are either 4″X4″ or 5″X5″; if anyone knows the size–or can measure!–put it in the comments.)
There’s a chameleon (Chamaeleo sp.). I’ve not attempted to determine the species. (It could be intended to be a species in another genus in the family Chamaeleontidae, but Chamaeleo is the type genus, and will do as at least approximately correct.) A nice detail is that the zygodactlous left front foot (‘hand’) can be seen grasping the black tiles, as though the latter constituted a tree branch. (The hind feet are curiously stubby-looking.)
Snakes are, of course, just glorified lizards. This one’s head and neck, and the fact that it hangs from the ‘branch’ make it look like a vine snake, but I’ll offer no more of a guess than that. Note how, as in the Chamaeleo above, the artwork can ‘overlay’ the regular wall design.
Next is a fairly nondescript snake, superimposed on the long tail of a long-necked sauropod dinosaur. The whole dinosaur looked like Diplodocus to me.
Having finished the order Squamata, we move on to the Tuatara (Sphenodon punctatus), not a lizard, but the sole living member of the order Rhynchocephalia. This is another of my favorites.
This broad-snouted crocodilian looks like an alligatorid, and is nicely paired with a Stegosaurus. Were it black, I would readily identify it as an American Alligator (Alligator mississippiensis), but the greenish-brown color makes me hesitate. The details of form in this one are not as satisfying as they are in most of the others. Note how the tail tip, which extends on to the dark paving tiles of the floor and trim, is rendered in a different type of tile.
Next is another favorite, an adult male Gharial (Gavialis gangeticus). The two things I like most about this one are the inclusion of the narial excrescence, a rarely depicted seasonally-present secondary sexual character of male gharials, and that the dark paving tile stones are treated as the ‘water’, from which the Gharial emerges. The dark stone is replaced with a lighter brown granite-like material to indicate the parts ‘underwater’. If you enlarge the image and look carefully, you can see that the outline of the Gharial is also continued into the glossy black enamel tiles. Although not visible in this photo, the body curls through the enamel tiles, and the Gharial’s tail re-enters the paving tiles, to again be represented by the granite-like stone.
Finishing up the reptiles we have a giant tortoise. The surviving species of giant tortoise are from Aldabra Atoll in the Indian Ocean and the Galapagos Islands in the Pacific. The somewhat high front opening of the carapace is more characteristic of some of the subspecies of the Galapagos Tortoise (Geochelone elephantopus) than of the Aldabra Tortoise, and so I will go with that as a species identification.
We’ll finish off our subway tour with the amphibians and a few fish tomorrow.
These photos were submitted by Leo Zaibert, who came across this turtle while out for a walk near his house in upstate New York, which is close to the Mohawk River. He was very impressed by its size and prehistoric demeanor, and surmised it was a snapping turtle (Chelydra serpentina), which indeed it was.
It was crossing the road, heading toward the Mohawk, which Leo estimated to be about 100 yards away. At this point along the Mohawk the river is bordered by wetlands, which is probably where snapping turtles in the river would spend most of their time. The turtle stopped as Leo approached, assuming a more defensive posture. In the water a snapper will run away, but on land they raise and direct their shell toward a threat, and will bite. There are good summaries of snapper biology available on the web by the Virginia Herpetological Society and the Savannah River Ecology Lab, and for the truly dedicated a monograph edited by Anthony Steyermark, Michael Finkler, and Ronald Brooks (2008).
This is a large adult. My guess is that it’s a female out looking for a nesting site. They need diggable soil in an area that won’t flood, so they need to be a few feet (at least) in elevation above the level of the water body they live in, and this can lead to them wandering along the roads, and even digging nests sometimes in the unpaved shoulders on the side of the road. In many turtles females are bigger than males, but in snappers males are larger. You can see a fairly luxuriant growth of algae on the snapper’s carapace, which is fairly typical. The algae has dried a bit, as the turtle has probably been wandering around on land for a bit.
Leo estimated its size at 40 inches, but I think this is an overestimate. The size of a wild animal, especially a bulky one like a snapper, is often overestimated, but this is not so much an error as a reaction to the unexpected appearance of an impressive beast. Snappers have big heads, long necks, and long tails, which adds to the impression of size: the tail is a bit shorter than the shell length, and the extended neck is quite long too, so that the total length of a snapper is well over twice the shell length.
My fairly large snapper (I went up to my lab and measured after getting Leo’s photos) is 10 3/8 inches straight line in the midline shell length, 8 inches tail length (the tip was infected and fell off many years ago, so would probably be about 8.5 inches), and the neck and head stretched out 7 inches toward my finger, but could probably reach a few inches more (I didn’t want my finger close enough to actually elicit a strike!), for a total length of 25+ inches, but less than 30 inches. A really big snapper would be about 14 inches in shell length, which would be about 35 inches total including neck and tail. (The record shell size for the species is 19 inches, which would make it over 40 inches in total length.)
Leo, who wished it to be recorded that he is a “noted expert on herpes or something”, is a philosopher, and reported that on a previous gallivant along the banks of the river that he miraculously emerged from the “treacherous quicksand of the Mohawk”, though I suspect it was deep mud, myself.
Steyermark, A.C., M.S. Finkler and R.J. Brooks. 2008. Biology of the Snapping Turtle(Chelydra serpentina). Johns Hopkins University Press, Baltimore. JHU Press
Please send in your photos. I will probably put this feature on hold while I’m in Texas, but, except when I’m gone, the tank is always emptying.
Today’s photos come from regular Tony Eales, an anthropologist in Queensland who loves natural history. Tony’s captions and IDs are indented, and you can enlarge his photos by clicking on them.
Tropical North Queensland part II (part I is here)
Here are a few of the other wonderful organisms I encountered on my brief trip up north to the jungles.
Australian Prismatic Slug (Atopos cf australis). I’m pretty sure there are several species of this slug around, but they all seem to be labelled A. australis. They are predatory slusg with curved teeth in the radula, and they spit acid onto snail shells to help rasp through to the snail inside.
The tracks at Speewah Conservation Park were empty of other humans, which was great for spotting wildlife. I got to approach this Northern Tree Snake (Dendrelaphis calligaster) quite closely without alarming it too much. It’s a slightly built rear-fanged colubrid and presents no danger to humans.
These beautiful Tropical Rockmasters (Diphlebia euphoeoides), a type of flat-wing damselfly, were common around Cairns and the surrounding area. I wish we had such beauties near me. This photo shows a male and female at Lake Eacham.
This is a lichen-mimicking caterpillar, Enispa prolectus. These caterpillars fasten small pieces of lichen to their backs with silk as a form of camouflage.
As the area is a tropical rainforest and it was actually raining while I was there, I was inevitably attacked by many, many leeches. However, I spotted this one (Haemadipsa sp.) on a railing at night actively questing, and I was struck by the bright colours. I have to wonder, are these colours signals to each other, warning, camouflage or just random?
One for Mark Sturtevant: a Pisuarid spider, related to the Dolomedes triton that he featured recently. This one is Hygropoda lineata. These were very common in the north. Rather than living by the water, these spiders make a simple web platform across the surface of broad leaves and sit on top of it, often looking like they are hovering in thin air.
Nephila pilipes, the Giant Golden Orbweaver. These are well named. We have Golden Orbweavers at home, which are big spiders, but these northern ones are mind bending. This one had a body length of about 50mm and was eating a cicada the size of my thumb. The span of the web was about 6 metres from attachment to attachment and the main orb about a metre and a half across.
They are only weakly venomous to humans and very reluctant to bite even when handled, preferring just to climb away.
There were a huge variety of amazing ant species to be found in the forests, but by far the most common were the Green Weaver Ants,Oecophylla smaragdina. I was always checking their trails for signs of the spiders that mimic them. Unfortunately, I didn’t find any. I did however observe their interesting behaviour of holding leaves together like living stitches. Inside the ball of leaves larvae are being hatched. The larvae are then taken by workers and produce silk to tie the leaves together more permanently.
In Speewah Conservation Park there were lots of climbing palms, Calamus caryotoides. The mature stems are festooned with black spines to ward off herbivores. However, these caterpillars, which I’ve yet to ID, use the spines to create a protective home as the crawl around and eat the leaves.
These long-jawed orbweavers, Tetragnatha rubriventris, were very common around Cairns. They have massive hinged chelicerae and the males have large clubbed pedipalps with complicated spiralled spines for placing a sperm packet into the female epigynum. all this weirdness makes them great photo subjects for a really alien look.
Also in Speewah Conservation Park I found this amazing fruiting bodies of the slime mould Tubifera microsperma.
Today’s lovely photos come from Tony Eales in Queensland, and are a potpourri of plants and animals. His captions are indented, and you can click on the photos to enlarge them.
I was recently in tropical north Queensland for work and decided to take a couple of days ‘time off in lieu’ that was owed me and visit the world heritage rainforests of the Atherton Tablelands.
Oh my ceiling cat! I managed to tick off three of my life-time bucket-list organisms in two days, along with many other amazing species which I’ll send in another email.
First the setting. I spent my days searching around the Lake Eacham National Park. The centrepiece of the park is a crater lake in an extinct volcanic caldera but I was told about an unsigned track down a closed road that went into the forest to some cascades on Wrights Creek that runs between Lake Eacham and Lake Barrine.
At night I went to Curtain Fig National Park, which is a small patch of primary forest just outside the little town of Yungaburra.
It was in this little forest that I saw my bucket-list creatures.
A Boyd’s Forest Dragon (Lophosaurus boydii). I was searching through hanging leaves at night looking for insects and spiders to photograph when I found myself almost eyeball to eyeball with this beautiful lizard.
Lucky too, for during the day they have a habit of moving around the tree trunk such that it is always between you and the lizard, thus you often pass them without ever knowing they are there.
The last night I was there I stayed in the forest on dusk, hoping to catch a glimpse of the Lumholtz’s Tree Kangaroos (Dendrolagus lumholtzi) that I knew lived there. I gave up and went back to town to sit by the Platypus viewing platform hoping I’d have better luck with the monotremes. There, right beside the main road in a tree next to the bridge, was a tree kangaroo.
And the most exciting for me though perhaps not for everyone, I saw my first Velvet Worm. I have a real thing for small phylum. These creatures have fascinated me ever since I learned of them in high school biology then later when they were featured in David Attenborough’s 2005 documentary Life in the Undergrowth. Now I have finally seen one I am not disappointed. They are amazing to watch move but I hope one day to see one take down prey.
This one is in the family Peripatopsidae or Southern Velvet Worms—the only Velvet Worm family in Australia.
I missed out on seeing the famous Stalk-eyed Flies in Borneo that are in the family Diopsidae. However, at Curtain Fig NP I was able to ‘next-best-thing’ it with Stalk-eyed Signal Flies (Achias sp.) in the family Platystomatidae. I was very pleased.
A new paper in Scientific Reports, which you can access below, describes the world’s smallest known reptile, a miniscule chameleon found in a small area of Madagascar, and named Brookesia nana. Indeed, it’s the smallest of all known amniotes, a group that includes reptiles, birds, and mammals. Two individuals of this species these were caught in 2012—a male and a female—and were just described as members of the new species.
First, a photo, just to show you how small it is. Below is an adult male, the “holotype” specimen (the one preserved individual used to characterize and represent the entire species). It sits comfortably atop a fingertip.
The size of this bad boy: its snout-to-vent length is 13.5 mm (0.53 inches!), and total length including the tail is 21.6 mm (0.85 inches). It’s about half an inch long: get out a ruler to see how small that really is! The female specimen, captured around the same time, is a bit bigger: 19.2 mm snout-vent length and 28.9 mm total (0.76 inches and 1.13 inches, respectively). Here are a few more pictures of both specimens (sadly, they killed both individuals to preserve them):
Click on the screenshot below to see the paper, or get the pdf here. The full reference is at the bottom, and there’s a short popular precis at IFL Science.
The species resides in a group (“clade”) of other miniature chameleons in the genus, with none longer than 30 mm total. The species name nana comes from the same Greek-Latin root that gives us “nano”, meaning “small.” The authors also did DNA analysis to place the species within its group, but we needn’t go into that, as the results are useful only to herpetologists.
The interesting thing about this species, as well as its relatives, is that they’re tiny and also extremely geographically restricted. They’re all found in montane (“mountainous”) rainforest. Here’s a distribution map of the related species in Madagascar, and you can see that no species was found outside of a range of about 100 km (60 miles). B. nana (yellow star) was found in only one place, and there may be very few individuals in the species. Most of the species are likely to be endangered: the authors note that the habitat of B. nana (now in a supposedly “protected area”) is being nibbled away by human depredation through slash-and-burn agriculture. If these things can breed in captivity, they might get a few in, for Madagascar is known for the loss of endemic species due to human disturbance.
All of the relatives of B. nana have females that are larger than the males, which is unusual for reptiles. B. nana, like its relatives, is an insect eater, and is probably arboreal (lives in trees), though the latter isn’t clear from the paper, for collecting information isn’t detailed.
A few other features of this group deserve mention. Unlike many chameleons, they lack head ornaments and spines or tubercules on their backs. Why? We don’t know. We also have no idea why individuals are so small, as their habitats don’t seem to particularly favor the evolution of miniaturization. It’s possible, but unlikely, that the two individuals they found happen to be extraordinarily small specimens, and not close to the species average. However, that would be a remarkable coincidence since they were found several days apart and were both sexually mature.
[Addendum by GCM:Brookesia nana may not be the world’s smallest lizard species, although it’s at least close. Reptiles have fairly indeterminate growth, so with a sample size of one of each sex, it’s hard to know what the maximum size is. I know a gecko species from the British Virgin Islands that has a maximum snout-vent length of 16 mm in males and 18 mm in females; I don’t know the species’ minimum size at sexual maturity. Body size in lizards is often reported as the maximum size known, which of course has problems as a statistic because it’s dependent on the outliers. To overcome this, Tom Schoener, in his studies of body size evolution and ecology of West Indian anoles, used to report the mean of the largest third of the sample as his body size statistic. With a sample of 1 per sex, this can’t yet be usefully done for the new species.]
One trait that may be comprehensible is the relatively large genitals of male B. nana. Like all lizards and snakes, males have a “hemipenis”, or bifurcated penis. Individuals mate by using only one of the two sides in each mating, alternating between matings. Because the female of this species is larger than the male by a substantial amount, nearly 50% (again, we don’t know why this disparity exists), the male has to have a relatively longer equipment to transfer sperm to the female. Here’s the male with the right hemipenis sticking out:
And closeups of the extruded left hemipenis, which is itself bifurcated. So we have the tiniest reptile known, one smaller than any other amniote, but also a well-endowed one. It’s ineffably cute (blunt snout, big eyes—all the traits that appeal to humans in baby animals), but also endangered. Right now we know very little about its ecology and behavior, though we know where it sits phylogenetically within its group of relatives. And we may not know a lot more before the species goes extinct.