Lizards with many tails, new research


This 2018 video is called Two tail lizard.

From Curtin University in Australia:

Double take: New study analyzes global, multiple-tailed lizards

July 7, 2020

Curtin research into abnormal regeneration events in lizards has led to the first published scientific review on the prevalence of lizards that have re-generated not just one, but two, or even up to six, tails.

PhD Candidate Mr James Barr, from Curtin University’s School of Molecular and Life Sciences, said while the phenomena of multiple-tailed lizards are widely known to occur, documented events were generally limited to opportunistic, single observations of one in its natural environment.

“This limited available research about multiple-tailed lizards has made it difficult for biologists to fully understand their ecological importance, and our study helps to highlight this knowledge gap,” Mr Barr said.

Many species of lizards have the ability to self-amputate a portion of their tail, an event known as caudal autotomy, as a defence mechanism when they are being attacked by a predator.

Most commonly the tail grows back as a single rod of cartilage, but Mr Barr explained that sometimes an anomaly occurs, resulting in the regeneration of more than just one tail.

“Sometimes following an incomplete autotomy event, when the lizard’s original tail does not fully separate from its body, a secondary tail regenerates, resulting in the lizard having two separate tails,” Mr Barr said.

“There have even been records of lizards re-generating up to six tails.

“Our study indicates that this phenomenon may actually be occurring more frequently in lizards than previously thought.

“We analysed the available two-tailed lizard data from more than 175 species across 22 families, from 63 different countries. Contrasting this data with all comparable lizard population numbers, our findings suggest an average of 2.75 per cent of all lizards within populations could have two tails or more at any one time.

“This is quite a surprisingly high number, and it really begins to make us wonder what ecological impacts this could have, especially noting that to the lizard, an extra tail represents a considerable increase in body mass to drag around.”

Co-researcher Curtin University Associate Professor Bill Bateman explained that while there is a significant lack of studies to understand these potential ecological impacts, his team believes that having two tails might affect the overall fitness and life history for individual lizards, and their overall populations.

“Shedding a tail to escape a predator and then regenerating it seems like a good tactic; however, when this regeneration goes awry and results in multiple abnormal tails, this is likely to have an effect on the lizard.

“It could affect a range of things, such as their kinetic movements, restrictions they might have when trying to escape a predator, their anti-predation tactics, and socially speaking, how other lizards might react to them,” Professor Bateman said.

“For example, could having two tails potentially affect their ability to find a mate, and therefore reduce opportunities for reproduction? Or on the contrary, could it potentially be of benefit?

“Behaviourally testing out these hypotheses would be an interesting and important future research direction, so biologists can learn more about the lifestyles of these multiple-tailed lizards.”

‘Extinct’ lizard rediscovered in Sumatra, Indonesia


This 4 June 2020 video, in Indonesian, is about the rediscovery after over a century of Modigliani’s lizard.

By Dyna Rochmyaningsih today:

A nose-horned dragon lizard lost to science for over 100 years has been found

Indonesia’s Modigliani’s lizards are bright green but can shift shades like a chameleon

Nearly 130 years ago, Italian explorer Elio Modigliani arrived at a natural history museum in Genoa with a lizard he’d reportedly collected from the forests of Indonesia.

Based on Modigliani’s specimen, the striking lizard — notable for a horn that protrudes from its nose — got its official taxonomic description and name, Harpesaurus modiglianii, in 1933. But no accounts of anyone finding another such lizard were ever recorded, until now.

In June 2018, Chairunas Adha Putra, an independent wildlife biologist conducting a bird survey in a mountainous region surrounding Lake Toba in Indonesia’s North Sumatra, called herpetologist Thasun Amarasinghe. Near the lake, which fills the caldera of a supervolcano, Putra had found “a dead lizard with interesting morphological features, but he wasn’t sure what it was,” says Amarasinghe, who later asked the biologist to send the specimen to Jakarta.

It took only a look at the lizard’s nose-horn for Amarasinghe to suspect that he was holding Modigliani’s lizard. “It is the only nose-horned lizard species found in North Sumatra,” he says.

Wooden arts and folktales of the Bataks — indigenous people native to the region — show that lizards have a special place in the people’s mythology. “But simply there was no report at all about this species” following Modigliani’s, says Amarasinghe, of the University of Indonesia in Depok.

He asked Putra to get back to the caldera to see if there was a living population. After five days, Putra found what he was looking for one evening, “lying on a low branch, probably sleeping,” according to the biologist. He took pictures of the lizard and measured the size and shape of its body parts, such as the length of its nose-horn and head. He also observed its behavior before finally releasing it the same night.

Using this data, Amarasinghe compared the lizard with the one described in 1933, and concluded that the living lizard and the dead one that Putra had stumbled across were in fact Modigliani’s nose-horned lizards. The Genoa museum’s dead specimen is pale blue due to preservation, but it’s now known that the lizard’s natural color is mostly luminous green. Its camouflage and tree-dwelling behavior are similar to African mountain chameleons, Amarasinghe, Putra and colleagues report in the May Taprobanica: The Journal of Asian Biodiversity.

The reptile belongs to the Agamidae family of lizards, which are commonly called dragon lizards and include species such as bearded dragons (SN: 6/14/17). Shai Meiri, a herpetologist at Tel Aviv University, has previously shown that many dragon lizards live in small, hard-to-access areas, making the reptiles difficult to study. There are 30 agamid species that have never been seen since they were first described, and 19 species which are known from just a single specimen, Meiri says.

While thrilled with their find, Amarasinghe and Putra are worried about the lizard’s future. “The living dragon was found outside a conservation area, and massive deforestation is happening nearby,” Amarasinghe says.

But the rediscovery offers a glimmer of hope for the lizard’s conservation, Meiri says. Before the reptile resurfaced, no one knew where exactly Modigliani’s lizard lived, or whether it had already gone extinct, he says. But now, “we can study it, understand its conservation needs and hopefully implement conservation measures.”

Amazing chameleons, video


This 1 June 2020 video says about itself:

Amazing chameleons! Colorful reptiles hunt, chameleon species from Africa, Madagascar, India!

Chameleons are amazing reptiles and among the most specialized lizards. They are great hunters with their rocket fast tongues, eyes moving independently, and great camouflage. Watch this video to learn the basic information about chameleons and see them in the wild. Enjoy the natural footage of hunting chameleons from Madagascar, beautiful three-horned chameleons, or tiny Namaqua Dwarf chameleon in the coastal desert of South Africa. Tiny chameleon – Brookesia, is also in this video! One of the biggest, Parson’s chameleon and one of the most famous, Panther chameleon, is there too!

Bermuda skink at empty Bermuda petrel nest


This video says about itself:

Bermuda Skink Visits Cahow Cam 1 Burrow – May 29, 2020

A Bermuda skink slinks into the recently fledged cahow chick‘s nesting burrow on the afternoon of May 29. Historically, these critically endangered skinks have a long-standing, important relationship with the cahows as they help keep the nests clean.

Greek islands lizards new love life


This 2018 video says about itself:

Erhard’s wall lizard (Podarcis erhardii), also called the Aegean wall lizard, is a species of lizard in the family Lacertidae. The species is endemic to Southeast Europe. Sithonia, Greece.

From Washington University in St. Louis in the USA:

Lizards develop new ‘love language’

Animal chemical signals shift after only four generations

April 21, 2020

Relocated in small groups to experimental islands, lizards rapidly and repeatedly developed new chemical signals for communicating with each other. Free from the risk of predators and intent to attract potential mates, male lizards produce a novel chemical calling card, according to new research from Washington University in St. Louis.

Studies of animal signal evolution usually focus on acoustic and visual signals — like the complex warbling in a bird’s song or the bright flashes of color on fish scales. Chemical signals between animals are less obvious to humans and more technically complex to parse. Much of the existing research on these signals has focused on insect pheromones relevant to certain agricultural applications.

But chemical signals are the oldest and most widespread communication mode, spanning bacteria to beavers. As such, they represent a valuable opportunity for decoding how animals communicate and perceive the world around them, researchers said.

“What we’ve discovered is that within species there is important variation in chemical signals depending on your context: Who’s trying to eat you, who wants to mate with you and who you’re trying to compete with,” said Colin Donihue, a postdoctoral fellow in biology in Arts & Sciences at Washington University in St. Louis and lead author of a new study published April 21 in the Journal of Animal Ecology.

Both lizards and snakes collect chemical cues from their surroundings by flicking out their slender forked tongues, then process those cues using a well-developed sensory organ in the roof of their mouths.

Lizards deposit their chemical messages encoded in secretions from specialized glands located on their inner thighs. The secretions are a waxy cocktail of lipid compounds that contains detailed information about the individual lizard that produced them.

In this study, researchers relocated groups of eight male and 12 female Aegean wall lizards (Podarcis erhardii) from a single source population in Naxos, Greece, to five small islets that lacked predators. Under normal conditions, these lizards would have to contend with a number of native and non-native predators — including snakes, birds and cats.

Free from predators on the small islets, the lizard populations grew rapidly and competition for resources was fierce.

Each of the relocated lizards was individually tagged so they could be identified when the researchers returned to check up on them. Over the next four years, the scientists revisited the populations, tracking the fates of the relocated lizards and their offspring.

What they found was striking: On each of the predator-free islands, lizards rapidly and repeatedly developed a new chemical “mix” that was distinct from that of lizards in the source population. The changes were apparent after only four generations.

For the first time, researchers believe that they have demonstrated solid evidence that lizards can “put on a new cologne” to suit their setting.

“Signals to attract mates are often conspicuous to predators,” said Simon Baeckens, a postdoctoral fellow at the University of Antwerp in Belgium and co-author of the new paper. “As such, sexual signals present a compromise between attractiveness and avoidance of detection. However, on these islets, there is no constraint on the evolution of highly conspicuous and attractive signals.

“In the experimental islands, we found that the ‘signal richness’ of the lizard secretions is the highest — meaning that the number of different compounds that we could detect in the secretion is the highest,” Baeckens added. “Our previous research suggests that this more elaborate signal might advertise the high quality of a male.”

Donihue continued: “Animals have spent over a billion years developing a complex chemical communication library. But we only invented the technology to identify many of those chemicals a century ago, and the experiments for understanding what those chemicals mean for the animals in nature have only just begun.

“We found that animal chemical cues can rapidly and flexibly change to suit new settings, but this is only the beginning for understanding what the lizards are saying to each other.”

New Caribbean black iguana species discovery


This 15 April 2020 video in Spanish is about the new discovery of a new Caribbean black iguana species.

From ScienceDaily:

A new species of black endemic iguanas in Caribbeans is proposed for urgent conservation

April 14, 2020

A newly discovered endemic species of melanistic black iguana (Iguana melanoderma), discovered in Saba and Montserrat islands, the Lesser Antilles (Eastern Caribbean), appears to be threatened by unsustainable harvesting (including pet trade) and both competition and hybridization from escaped or released invasive alien iguanas from South and Central America. International research group calls for urgent conservation measures in the article, recently published in the open-access journal ZooKeys.

So far, there have been three species of iguana known from The Lesser Antilles: the Lesser Antillean iguana (Iguana delicatissima), a species endemic to the northernmost islands of the Lesser Antilles; and two introduced ones: the common iguana (Iguana iguana iguana) from South America and the green iguana (Iguana rhinolopha) from Central America.

The newly described species is characterised with private microsatellite alleles, unique mitochondrial ND4 haplotypes and a distinctive black spot between the eye and the ear cavity (tympanum). Juveniles and young adults have a dorsal carpet pattern, the colouration is darkening with aging (except for the anterior part of the snout).

It has already occurred before in Guadeloupe that Common Green Iguana displaced the Lesser Antilles iguanas through competition and hybridization which is on the way also in the Lesser Antilles. Potentially invasive common iguanas from the Central and South American lineages are likely to invade other islands and need to be differentiated from the endemic melanistic iguanas of the area.

The IUCN Red List lists the green iguana to be of “Least Concern”, but failed to differentiate between populations, some of which are threatened by extinction. With the new taxonomic proposal, these endemic insular populations can be considered as a conservation unit with their own assessments.

“With the increase in trade and shipping in the Caribbean region and post-hurricane restoration activities, it is very likely that there will be new opportunities for invasive iguanas to colonize new islands inhabited by endemic lineages,” shares the lead researcher prof. Frédéric Grandjean from the University of Poitiers (France).

Scientists describe the common melanistic iguanas from the islands of Saba and Montserrat as a new taxon and aim to establish its relationships with other green iguanas. That can help conservationists to accurately differentiate this endemic lineage from invasive iguanas and investigate its ecology and biology population on these two very small islands that are subject to a range of environmental disturbances including hurricanes, earthquakes and volcanic eruptions.

“Priority actions for the conservation of the species Iguana melanoderma are biosecurity, minimization of hunting, and habitat conservation. The maritime and airport authorities of both islands must be vigilant about the movements of iguanas, or their sub-products, in either direction, even if the animals remain within the same nation’s territory. Capacity-building and awareness-raising should strengthen the islands’ biosecurity system and could enhance pride in this flagship species,” concludes Prof. Grandjean.

The key stakeholders in conservation efforts for the area are the Dutch Caribbean Nature Alliance (DCNA), the Saba Conservation Foundation (SCF), the Montserrat National Trust (MNT) and the UK Overseas Territories Conservation Forum (UKOTCF), which, the research team hope, could take measures in order to protect the flagship insular iguana species, mainly against alien iguanas.

New gecko species discovery in Cambodia


This October 2019 video says about itself:

Lizards of Peninsular Malaysia and Borneo. A complete list of all the species featured as well as their respective time stamps are as below: 0:04 Ornate Earless Agama (Aphaniotis fusca) 0:07 Great Anglehead Lizard (Gonocephalus grandis) 0:13 Frilled Gecko (Hemidactylus craspedotus)’s trophobiosis with Pyrops oculatus. 0:19 Green Crested Lizard (Bronchocela cristatella) 0:25 Beautiful Bent-toed Gecko (Cyrtodactylus elok) 0:34 Peters’ Bent-toed Gecko (Cyrtodactylus consobrinus) 0:37 Borneo Bent-toed Gecko (Cyrtodactylus malayanus) 0:44 Marbled Bent-toed Gecko (Cyrtodactylus quadrivirgatus) 0:46 Bell’s Anglehead Lizard (Gonocephalus bellii) 0:52 Tokay Gecko (Gekko gecko) 0:55 Viserion’s False Garden Lizard (Pseudocalotes viserion) 1:01 South Titiwangsa Bent-toed Gecko (Cytodactylus australotitiwangsaensis) 1:07 Brown’s Fringe Gecko (Luperosaurus browni) 1:13 Robinson’s Forest Dragon (Malayodracon robinsonii) 1:19 Kuhl’s Flying Gecko (Ptychozoon kuhli) 1:28 Sabah Flying Gecko (Ptychozoon rhacophorus) 1:34 Kinabalu Crested Dragon (Hypsicalotes kinabaluensis) 1:40 Smith’s Gecko (Gekko smithii) 1:47 Cat Gecko (Aeluroscalabotes felinus) 1:55 Blue-eyed Anglehead Lizard (Gonocephalus liogaster) 2:01 Peninsular Rock Gecko (Cnemaspis peninsularis) 2:04 Five-banded Flying Lizard (Draco quinquefasciatus) 2:10 Titiwangsa Horned Tree Lizard (Acanthosaura titiwangsaensis) 2:16 Doria’s Anglehead Lizard (Gonocephalus doriae)

From the North Carolina Museum of Natural Sciences in the USA:

Scientists discover bent-toed gecko species in Cambodia

April 13, 2020

A new species of bent-toed gecko (Cyrtodactylus phnomchiensis) has been described from Cambodia’s Prey Lang Wildlife Sanctuary by Wild Earth Allies Biologist Thy Neang in collaboration with North Carolina Museum of Natural Sciences’ Herpetologist Bryan Stuart. This new species is described in ZooKeys.

The species was discovered by Thy Neang during Wild Earth Allies field surveys in June-July 2019 on an isolated mountain named Phnom Chi in the Prey Lang Wildlife Sanctuary when he encountered an unusual species of bent-toed gecko. “It was an extremely unexpected discovery. No one thought there were undescribed species in Prey Lang,” said Neang.

The geckos were found to belong to the C. irregularis species complex that includes at least 19 species distributed in south¬ern and central Vietnam, eastern Cambodia, and southern Laos. This is the first member of the complex to be found west of the Mekong River, demonstrating how biogeographic barriers can lead to speciation. Additionally, the geckos were unique in morphological characters and mitochondrial DNA, and distinct from C. ziegleri to which they are most closely related. Researchers have named the species Cyrtodactylus phnomchiensis after Phnom Chi mountain where it was found.

Bent-toed geckos of the genus Cyrtodactylus are one of the most species-diverse genera of gekkonid lizards, with 292 recognized species. Much of the diversity within Cyrtodactylus has been described only during the past decade and from mainland Southeast Asia, and many of these newly recognized species are thought to have extremely narrow geographic ranges. As such, Cyrtodactylus phnomchiensis is likely endemic to Phnom Chi, which consists of an isolated small mountain of rocky outcrops (peak of 652 m elevation) and a few associated smaller hills, altogether encompassing an area of approximately 4,464 hectares in Kampong Thom and Kratie Provinces within the Prey Lang Wildlife Sanctuary, Cambodia.

The forest habitat in Phnom Chi remains in relatively good condition, but small-scale illegal gold extraction around its base threatens the newly discovered species. A second species of lizard, the scincid Sphenomorphus preylangensis, was also recently described from Phnom Chi by a team of researchers including Neang. These new discoveries underscore the importance of Prey Lang Wildlife Sanctuary for biodiversity conservation and the critical need to strengthen its management.

Further, an assessment of C. phnomchiensis is urgently warranted by the IUCN Red List of Threatened Species (IUCN 2020) because of its small area of occupancy, status as relatively uncommon, and ongoing threats to its habitat.

“This exciting discovery adds another reptile species to science for Cambodia and the world. It also highlights the global importance of Cambodia’s biodiversity and illustrates the need for future exploration and biological research in Prey Lang,” said Neang.

“When [Neang] first returned from fieldwork and told me that he had found a species in the C. irregularis group so far west of the Mekong River in Cambodia, I did not believe it. His discovery underscores how much unknown biodiversity remains out there in unexpected places. Clearly, Prey Lang Wildlife Sanctuary is important for biodiversity and deserves attention,” said Neang’s co-author Stuart of the North Carolina Museum of Natural Sciences.

New Smaug lizard species discovery in Africa


This February 2019 video from South Africa is called SAVING OUR “DRAGONS”. It is about sungazer lizards, the biggest species in the Smaug genus.

From the Florida Museum of Natural History in the USA:

Here be dragons: Analysis reveals new species in ‘Smaug’ lizard group

March 25, 2020

Smaug, the deadly dragon in J.R.R Tolkien‘s “The Hobbit“, has a few living relatives. With dense, alligator-like armor, these small, real-life dragon lizards are rock-crevice recluses mostly confined to mountaintops in southern Africa.

Now, herpetologists Michael Bates, a curator at South Africa’s National Museum in Bloemfontein, and Edward Stanley of the Florida Museum of Natural History have discovered a ninth species of dragon lizard in the genus Smaug, previously mistaken for a similar-looking species, S. barbertonensis.

The new species, a heavily plated dark brown lizard with pale yellow bands, has been named Smaug swazicus, or the Swazi dragon lizard, in honor of the country of Eswatini, where most of the species’ range is located. Up to 13 inches from snout to tail tip, S. swazicus is an unusually big lizard for the region.

“In terms of bulk and actual recorded total length, Smaug swazicus may be the largest southern African lizard species described since the western giant plated lizard, Matobosaurus maltzahni, 82 years ago,” Bates said.

While species in the Smaug genus, also known as girdled lizards, may have scaled-down versions of their fearsome namesake’s shield-like scales and sword-like teeth, they have gentle dispositions, Stanley said.

“They’re just little tanks,” said Stanley, who is also the director of the Florida Museum’s Digital Discovery and Dissemination Laboratory. “They hide in rock cracks and put a lot of their energy and effort into simply being spiky and inedible, so they don’t have to put up a big fight.”

Stanley led a group of scientists that named the Smaug genus in 2011, and he has been instrumental in parsing out its species. “Smaug”, he explained, comes from the German word “smugan,” which means “to squeeze through a hole.” These lizards are also found near South Africa’s Drakensberg Mountains, Afrikaans for “dragon mountains.”

While Africa has an enormous diversity of lizards, girdled lizards are the only family exclusive to mainland Africa and, because of their crevice-dwelling lifestyle, are often restricted to specific habitats. As a result, Stanley said more stringent conservation strategies may be needed for certain Smaug species.

“S. barbertonensis already had a relatively restricted range, but that’s obviously before it was split in half when S. swazicus was discovered,” Stanley said. “So, although barbertonensis wasn’t of concern before, it now has a range of only around 200 square miles,” an area less than the size of Chicago.

Tethered to high-elevation boulder-filled habitats, dragon lizards could already be feeling the effects of a warming climate, Stanley said. Securing rock crevices in which to hide could become challenging as dragon lizards creep to higher elevations in search of lower temperatures.

“These creatures are brilliantly evolved for their environment. If things aren’t done to protect them, we could lose 20 million years of evolution in 50 years,” he said. “The important thing is that you need to characterize and identify animals before you can protect them. You need to know what you have before you can make a plan to protect it.”

But finding lizards in southern Africa can be daunting: Stanley and his fellow researchers had to dodge everything from mambas to undetonated explosives. When team members expanded their search to well-shaded boulders on a military base, they were accused of being gold prospectors, thieves and pet trade dealers.

“We had to spend all morning explaining, ‘No, we’re not here for any of that — we’re really here just to try and find some lizards on your army base,'” Stanley said. “And in fact, because the range was so unpopulated, the lizards we found there were quite friendly. It was a weird experience having spent such a long time looking for them and then going into this sort of garden where they’d run on your lap and jump into your arms.”

Stanley’s next run-in with the new species wasn’t deep in the South African escarpment. He said he recognized the species from his time at the American Museum of Natural History, where there was a jar of unidentified pet trade specimens from the early 1980s in the herpetology collection.

“That’s the nice thing about museums, isn’t it? It’s not like these animals are sitting underground, never before seen. A lot of times they’re just hiding in plain sight,” he said.

To differentiate similar-looking species, Stanley and Bates relied on traditional approaches based on physical features, CT scanning and DNA analysis, a process he compared to sorting candy.

“Say you have different kinds of candies that you need to sort by type,” Stanley said. “You start by visually sorting all your M&M’s into one pile and your Mike and Ike’s in another.”

Then comes the DNA analysis — in other words, the taste test.

“So, you sample your candies, and you find that there are a proportion of M&M’s you’ve sorted that are actually Skittles, and then you notice that instead of an ‘M,’ they actually have a tiny ‘S’ on them,” Stanley said. “You can now pull these out and say, ‘Oh, I actually have three candies.'”

The new species of dragon lizard can be compared to the Skittles, Stanley said — similar in appearance to S. barbertonensis, but with slight genetic differences that show it’s more closely related to another species of dragon lizard, S. warreni. The analysis also allowed Stanley and Bates to parse minor physical differences that other researchers originally attributed to individual variation and helped explain why Bates’s previous examination of museum specimens had revealed three distinct color patterns in dragon lizards.

Stanley said he can’t rule out the possibility that more species in the group await discovery.

“Even now, in this well-worked group in these very populated countries of South Africa and Eswatini, that have had a lot of herpetologists working for hundreds of years, there are still some cool discoveries to be made,” he said. “That’s the biggest part of the story for me, is that there are some awesome animals out there just undescribed.”

Blue iguanas fight against extinction


This 14 March 2020 video from the Cayman Islands says about itself:

Blue Iguana Fights Extinction and Wins!

On this episode of On Location, Mark and the crew are in one of the most remote parts of Grand Cayman Island to meet a lizard that was brought back from the brink of extinction! The Blue Iguana is one of the most beautiful and rarest iguanas on the planet. Meet Peter, a true ambassador for his species!

Get ready, you’re about to see a blue iguana that fought extinction and WON!