Yahoo News 6 Apr 10;
PARIS (AFP) – Biologists on Wednesday reported the spectacular discovery of a species of giant lizard, a reptile as long as a full-grown man is tall, and endowed with a double penis.
The secretive but brightly-coloured beast, a monitor lizard, is a close cousin of the Komodo Dragon of Indonesia.
But unlike the fearsone Dragon, it is not a carnivore, nor does it feast on rotting meat. Instead, it is entirely peaceable and tucks into fruit.
Dubbed Varanus bitatawa, the lizard measures two metres (6.5 feet) in length, according to the account, published by Britain's Royal Society.
It was found in a river valley on northern Luzon Island in the Philippines, surviving loss of habitat and hunting by local people who use it for food.
How many of the lizards have survived is unclear.
The species is almost certainly critically endangered, and might well have disappeared entirely without ever being catalogued had a large male specimen not been rescued alive from a hunter last June.
Finding such a distinctive species in a heavily populated, highly deforested location "comes as an unprecedented surprise," note the authors, writing in the journal Biology Letters.
The only finds of comparable importance in recent decades are the Kipunji monkey, which inhabits a tiny range of forest in Tanzania, and the Saola, a forest-dwelling bovine found only in Vietnam and Laos.
V. bitatawa has unique markings and an unusual sexual anatomy, according to the study.
Its scaly body and legs are a blue-black mottled with pale yellow-green dots, while its tail is marked in alternating segments of black and green.
Males have a double penis, called hemipenes, also found in some snakes and other lizards.
The two penises are often used in alternation, and sometimes contain spines or hooks that serve to anchor the male within the female during intercourse.
V. bitatawa has a relative in southern Luzon, V. olivaceus, but the species are separated by three river valleys and a gap of 150 kilometers (95 miles) and may never have met up.
One reason that the new lizard has gone undetected, the researchers speculate, is that it never leaves the forests of its native Sierra Madre mountains to traverse open spaces.
The discovery "adds to the recognition of the Philippines as a global conservation hotspot and a regional superpower of biodiversity," the authors conclude.
The giant lizard should become a "flagship species" for conservation efforts aimed at preserving the remaining forests of northern Luzon, which are rapidly disappearing under the pressure of expanding human population and deforestation.
Philippines dragon-sized lizard is a new species
Deborah Zabarenko Reuters 6 Apr 10;
WASHINGTON (Reuters) - A dragon-sized, fruit-eating lizard that lives in the trees on the northern Philippines island of Luzon has been confirmed as a new species, scientists reported on Tuesday.
Hunted for its tasty flesh, the brightly colored forest monitor lizard can grow to more than six feet in length but weighs only about 22 pounds (10 kg), said Rafe Brown of the University of Kansas, whose team confirmed the find.
"It lives up in trees, so it can't get as massive as the Komodo dragon, a huge thing that eats large amounts of fresh meat," Brown said by telephone. "This thing is a fruit-eater and it's only the third fruit-eating lizard in the world."
Discovering such a large vertebrate species is extremely rare, Brown said. The lizard, a new species of the genus Varanus, is skittish and able to hide from humans, its primary predators, which could explain why it has gone undetected by scientists for so long.
Biologists first saw photographs of the big, skinny lizard in 2001, when those surveying the area passed hunters carrying the lizards' colorful carcasses, but the species at that point had never been given a scientific identification.
In the next few years, Brown said, ethnobiologists kept hearing stories "about these two kinds of lizard that everyone liked to eat because their flesh tasted better than the ones that lived on the ground; this thing was described as bigger and more brightly colored."
The two kinds of lizard described by the local people were two names for the same animal, Brown said.
CLAW SCRATCHES ON TREES
In 2009, graduate students at the end of a two-month expedition kept seeing signs of the big lizard. There were claw-scratches on trees and clumps of pandanus trees, whose fruit the lizard prefers.
The clumps indicated that the lizards had eaten pandanus fruit and then excreted the seeds in clusters.
"It was literally in the last couple days of the expedition, we were running out of money and food and this was the payoff: they finally got this gigantic animal," Brown said.
Hunters who had heard of the team's interest brought a barely-alive adult male lizard to their camp. The team euthanized the animal and did genetic tests that confirmed it as a unique species, Brown said.
DNA analysis showed there was a deep genetic divergence between the new lizard and its closest relative, Gray's monitor lizard, which is also a fruit-eater but lives on the southern end of Luzon, rather than the northern end where the forest monitor lizard lives.
"They are extremely secretive," Brown said of the new species. "I think that centuries of humans hunting them have made the existing populations ... very skittish and wary and we never see them. They see and hear us before we have a chance to see them, they scamper up trees before we have a chance to come around."
These findings were published in the Royal Society Journal Biology Letters, with additional work by scientists in the Philippines and the Netherlands.
(Editing by Sandra Maler)
Giant Lizard Eluded Science, Until Now
Charles Q. Choi, livescience.com 7 Apr 10;
A giant, spectacularly colored new species of monitor lizard has just been revealed to scientists in the Philippines.
The reptile, which is roughly 6 feet long (1.8 meters), is kin to Komodo dragons, the world's largest lizards. Named Varanus bitatawa, this newly discovered species, decorated in stripes of gold flecks and armed with huge, curved claws for climbing trees, is one of only three fruit-eating monitor species in the world.
New to science, not residents
As humans continue to explore the last uncharted regions of the planet, discoveries of previously unknown species of large vertebrates have become rare. It remains doubly surprising this reptile managed to escape the attention of the many biologists that work on the heavily populated island of Luzon.
"I am most impressed that such a large, conspicuous, brightly colored species of monitor lizard escaped the notice of biologists for the past 150 years," said researcher Rafe Brown, a field herpetologist at the University of Kansas.
Still, remarkably few surveys have explored the reptile diversity of the island's northern forests. The reptile also seems highly secretive and dislikes traversing open areas.
"At the same time, we are humbled because the species is not really new - it is only new to us as Western scientists," Brown said. "In fact, resident indigenous communities - the Agta and Ilongot tribes - have known about it for many generations. If only scientists had listened to them earlier!"
Discovering the giant
Rumors of the lizard's existence floated among biologists for the past 10 years, Brown explained.
"People had taken photographs of hunters from the resident tribespeople as they were carrying the reptiles back to their homes to feed their families in 2001," Brown said.
In 2005, two different groups procured juvenile specimens. "However, both of those efforts didn't collect genetic samples, so we couldn't yet prove that it was genetically distinct and didn't just look different," Brown said. "Also, we wanted a full-sized adult to see how big it got in life."
Last summer, the researchers set out on a two-month expedition to scour the forests for the animal. "We began in July, and the rainy season began early that year, so we were just working in a deluge the whole time," Brown recalled. "Getting up those mountains with a big team of 20 people and all their equipment and gear in those muddy conditions was difficult."
"We knew it was there in the forests around us," he added. "We had seen its scratch marks on trees, we had seen its footprints along stream banks, and we had found its scat."
Near the very end of their complicated, exhausting trip, when they were low on food and out of money, they got a large adult male specimen, captured by the snares of a tribal hunter. "It was like a prize at the end of a marathon," Brown said.
The Agta and Ilongot tribes call the reptile "bitatawa," which the new scientific name for it reflects, and rely on the animal for its meat.
"I have not tasted it myself - the specimen we caught was too important for us to just try," Brown said. "I only know the hunters report it as better tasting and less smelly than the other monitor lizard in the area, a scavenger."
Science of the lizard
Although closely related to the slightly smaller Gray's monitor lizard (Varanus olivaceus), it remains separated from its cousin by a more than 90-mile (145 km) stretch that includes at least three river valley barriers. Genetic analysis confirms V. bitatawa is a new species, as do its coloration, scales, body size, and reproductive anatomy.
"Lizards keep their male reproductive organs inverted inside their bodies like a sock turned inside out, and when it's time to use them, they evert them, flipping them out of their body and filling them with fluid so they can rigidly protrude for reproduction," Brown said. "We call this a hemipenis, and lizards have two of them. They have elaborate structures that we assume are unique to each species - we think they have to fit like a lock and key, preventing hybridization between species."
Both males and females seem to possess golden stripes. "In general, reptiles are very visual, so the different coloration may serve as a signal to other members of its own species," Brown said. "Bright coloration often helps reptiles find and attract mates."
The new species is a keystone in its environment. It eats the fruit of the palm-like Pandanus trees, "and as the seeds travel through its gut, it helps remove their coats so they germinate faster, thus promoting forest growth," Brown said. "You see these trees growing in little circles like fairy rings, evidence that this lizard came by, spreading the seeds around the forest by dropping a bunch of scat."
The researchers expect the lizard to instantly become a flagship species for conservation.
"Given that rapid deforestation in the major threat to many Philippine species, especially the ones restricted to areas with tree cover, we suspect that the new species is a major conservation priority," Brown said. "We need to know the size of its home range, exactly what it eats, how long it takes to mature, how often it breeds, and details of its ecology and population structure."
Efforts to defend the lizard's forested habitat could help protect many hundreds to thousands of unrelated animals and plants as well, they added.
"It is a Philippine national treasure," Brown said.
Brown and his colleagues detailed their findings online March 7 in the journal Biology Letters.
Spectacular discovery
Angel Alcala Malaya 6 May 10;
THE newspaper announcement that the giant 2-meter golden-spotted monitor lizard discovered in the Sierra Madre Mountains in northern Luzon in 2004 is a new species is indeed great news for the Philippines. The unexpected discovery once more gives evidence for the recognition of the Philippines as a megabiodiversity country.
We should be thankful to the local people for bringing to the attention of field workers the occurrence of the species in the Sierra Madre Mountains. We should also congratulate the University of Kansas herpetologists led by Dr. Rafe Brown and the Filipino herpetologist Arvin Diesmos of the Philippine National Museum for their genetic study proving that the species is new to science.
I wish that the discovery was published in a refereed Philippine journal such as the Philippine Journal of Science, where the discovery would have conferred prestige to our own publications. It was instead published in the Royal Society journal Biology Letters. I think that the Philippine science authorities should urge scientists working on Philippine biodiversity to also publish new discoveries in Philippine journals.
The new lizard species, scientifically named Varanus bitatawa, found in northern Luzon, is the second species of the genus Varanus reported from the island of Luzon, the Philippines. The other species on Luzon is Varanus olivaceus, long known in the Bicol region and, like the new species, is also arboreal occurring in rainforests. This gives rise to the question, how are these two species related. One can expect that in the past these two species probably overlapped in distributional range and therefore were likely to exchange genes.
Other species of the genus include Varanus mabitang (in northwest Panay) and the widespread Varanus salvator group, which has been split into several distinct species locally known as "bayawak" or "halo." As of this time, my German colleague, Dr. Maren Gaulke, tells me that the three populations of V. salvator earlier referred to as subspecies are now recognized as full species. Therefore, there are now at least six known species of Varanus in the Philippines. The expectation is that there are more species of this genus to be discovered in Philippine tropical rain forests such as those on Mindanao and Samar, if only a careful search is mounted using native observers.
The three species (V. olivaceus, V. bitatawa, V. mabitang) appear to inhabit trees in original forests and presumed to be primarily vegetarian in food habits. The salvator group are all carnivorous, like the famous Komodo Dragon of Indonesia. All six species should be conserved by preserving their habitats.
It must be pointed out, however, that the new species (V. bitatawa) is not related closely to the Komodo Dragon, according to my German colleague Maren Gaulke, contrary to the claim in the press release published in the Internet.
The fact that it took a long time to discover this species in its natural habitat is not surprising at all. Walter Brown and I discovered at least three species (one frog and two lizards), all new species in areas frequented by herpetologists and other natural history workers by using intensive search methods and in the case of frogs, by the sounds made by males (as female frogs are largely silent).
There are implications of the discovery of the new species of Varanus. First, the Philippine government through DENR should strengthen the management of the Sierra Madre Mountains as well as other original rain forests to prevent the destruction of the only habitats of the new lizard and other forest species of Varanus, the tropical rain forests. This is the opportunity to show that we are serious in our pronouncements to conserve our endemic, charismatic and flagship species by concrete action. It is a challenge to the DENR and the PAWB to appropriate funds to conserve the habitats of the many species of biodiversity in our tropical rain forests.
Secondly, the government should mobilize a team of Filipino biologists known for their works on reptiles and amphibians (not just anybody) to fully explore the Sierra Madre and other wilderness areas of the country for new species and see to it that the reports are published in our science journals or in a book specifically dealing with the vertebrate species in the area. I recommend Dr. Arvin Diesmos as part of the team.
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