NewCritters.com

Here’s some BIG dino news for you! Fossils of a new giant carnivore have been found in Argentina. Interestingly, a group of the animals were found together leading researchers to believe they may have hunted in packs.

Paleontologists Rodolfo Coria and Philip Currie recently published their discovery of Mapusaurus roseae in Geodiversitas, A new carcharodontosaurid (Dinosauria,Theropoda) from the Upper Cretaceous of Argentina. [pdf]

Now the question is, who was bigger - Mapusaurus, Giganotosaurus, or Spinosaurus?

The genus name, Mapusaurus, means “Earth Reptile”. It comes from the Mapuche word for earth, mapu. The Mapuches are an indigenous people of Patagonia.

The species name, roseae refers to the rose colored rocks that surround the site where the fossils were found, and to Rose Letwin who sponsored expeditions that lead to the discovery.

(photo by Rodolfo Coria)

There are many sites reporting on this discovery. Here are links to a few.

CTV.ca News: Dig finds largest known carnivorous dinosaur.
NewScientist Giant dino-predators may have hunted in packs
Express News, Uni of Alberta: Huge meat-eating dinosaur uncovered

Lastly, here’s some Mapusaurus inspired Art at DeviantArt

Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Saurischia
Suborder: Theropoda
Infraorder: Carnosauria
Family: Carcharodontosauridae
Subfamily: Giganotosaurinae
Genus: Mapusaurus

A new species of freshwater stingray has been discovered in a river in western Thailand, but its chances for long-term survival are slim, warns WWF.

The new species of stingray, measuring 60 centimeters (23.6 inches) in width, was first observed two years ago but has only now been confirmed in detail as a new species by researchers from WWF-Thailand and the US-based Smithsonian Institute.

WWF Thailand’s Senior Freshwater Biologist, Dr Chavalit Vidthayanon along with Smithsonian Research Associate, Dr Tyson Roberts, have described in detail the new freshwater stingray, known as Himantura kittipongi, found in the Mekong Basin of western Thailand.

Thai rivers, including the Mekong River where the ray is found, have been plagued by serious pollution, overfishing and dam building which have taken a deadly toll on Thailand’s once diverse and abundant river life. The ray is believed to exist in only small numbers.

The new species was named Himantura kittipong after prominent Thai fish expert Kittipong Jaruthanin who first observed the ray in 2004. *

The researcher’s described their discovery in the Natural History Bullitin of the Siam Society, however, no recent information about the publication is available online.

Also see The Nation’s article, New ray discovered in Kanchanaburi.

Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Rajiformes
Family: Dasyatidae
Genus: Himantura

* text used with permission © 13 Apr 2006 WWF - the environmental conservation organisation . Some rights reserved.

In two related articles highlighted on the April 6 cover of the journal Nature, Dr. Ted Daeschler of The Academy of Natural Sciences in Philadelphia, co-leader of an expedition 600 miles north of the Arctic Circle, and his colleagues announced the discovery of 375-million-year-old fossils with numerous features that place them squarely at the evolutionary transition from fish to limbed animals. The new species has a skull, neck, ribs and part of a fin like the earliest limbed animals, but also has fins and scales like a fish. For about a century, scientists have been able to trace the broad outline of the millions-of-years-long transition of lobe-finned fish to limbed animals (tetrapods). The new species, named Tiktaalik roseae, however, is the most compelling evidence yet of an animal that was on the verge of the transition from water to land. It shows that the evolution from life in water to life on land happened gradually in fish living in shallow water.

T. roseae was a predator with sharp teeth, a crocodile-like head, and a flattened body that lived in what was then a subtropical climate. The quality of the fossils allowed the team to examine the joint surfaces on many of the fin bones and figure out that shoulder, elbow and wrist joints were capable of supporting the body like limbed animals. “Tiktaalik blurs the boundary between fish and land animals,” said Dr. Neil Shubin of the University of Chicago, the other co-leader. “This animal is both fish and tetrapod; we jokingly call it a fishapod.”

The fossils were recovered from the layered rock of the so-called Fram Formation, the deposits of meandering stream systems formed some 375 million years ago when North America was part of a supercontinent straddling the equator. These fossils and previously known fossil relatives suggest the evolution from fish to tetrapod occurred on this landmass. “This kind of shallow stream system seems to be the place where many features of land living animals first arose,” said Daeschler.

The skeletal structure of T. roseae and the nature of the deposits where it was found suggest an animal that lived on the bottom of shallow waters and perhaps even out of the water for short periods. “The skeleton of Tiktaalik indicates that it could support its body under the force of gravity whether in very shallow water or on land,” said Dr. Farish A. Jenkins of Harvard University, another collaborator. “This represents a very critical early phase in the evolution of all limbed animals, including us.”

Instead of using the traditional Latin or Greek to name the fossil, the team consulted Nunavut residents, who suggested Tiktaalik (tic-TA-lick), the Inuktikuk word for large, shallow water fish. The second part of the name, roseae, honors an anonymous supporter.

Tiktaalik has a flattened, triangular-shaped skull reminiscent of the earliest tetrapods. Although the lower jaws and snout have fish-like features, the rear portion of the skull looks more like a limbed animal. The skull is significantly shortened behind the eye sockets and has deep notches in its rear margin. The bones that connect the skull to the shoulders in fishes are not found in Tiktaalik, also hinting at its tetrapod-like nature. An intermediate stage in the transition from fin to limb is also seen in the bones of the pectoral fins, which show robust skeletal elements indicative of powerful and mobile appendages, flexible at shoulder, elbow and wrist, while retaining a reduced set of the thin rods found in fish fins. The wide, flattened body of Tiktaalik is also tetrapod-like but is covered by scales as in fish.

Photo of fossil by Daeschler
Illustration by Kalliope Monoyios

T. roseae has already inspired artists, check out TrollArt for some funky drawings! There’s also an entire website dedicated to Tiktaalik roseae over at the University of Chicago. There’s a video interview and more information about the expedition that lead to the discovery.

A new species of woolly lemur first spotted in 1990 by researchers was officially announced this past November.

The animals are known locally as Dadintsifaka which means ‘grandparent of sifakas’ (Propithecus deckeni) because they are smaller and greyer than the white sifaka lemur. The species was given the scientific name Avahi cleesei after the famous comedian and actor John Cleese.

Read the fascinating story [pdf] of researcher Urs Thulmann to learn more about this discovery as well as other lemurs and creatures of Madagascar. It details what happened over the 15 years between his initial sighting and the report giving the critters their zoological name.

You can also read the short scientific report published in the American Journal of Primatology [pdf] as well as hear audio clips of the new lemurs.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Indriidae
Genus: Avahi

Scientists from the University of Utah and the Utah Museum of Natural History have discovered the remains of a new bird-like, meat-eating dinosaur in Grand Staircase-Escalante National Monument, southern Utah.

The new dinosaur was formally named Hagryphus giganteus, which means “giant four-footed, bird-like god of the western desert” in reference to the animal’s outward resemblance to a large land bird, its giant stature, and its discovery in the Utah desert.

Only the hands and feet of Hagryphus were found, but the scientists were able to use the animal’s close relatives in Asia to estimate it to be around 7 feet tall! It is a member of the oviraptorosaurs, a group of bird-like feathered dinosaurs with toothless beaks, powerful arms and formidable claws. They are thought by some paleontologists to have been omnivorous, feeding on a mixture of meat and plants.

The scientific paper naming and describing this critter was published in the latest issue of the Journal of Vertebrate Paleontology, A new Oviraptorosaur (Theropoda, Maniraptora) from the Late Cretaceous (Campanian) of Utah (abstract only).

CNN also has a video interview with the paleontologists available online.

(Illustration by Michael W. Skrepnick)

Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Infraorder: Coelurosauria
Maniraptora
Oviraptoriformes
Oviraptorosauria

Juravenator starki is a small carnivorous theropod dinosaur from the Late Jurassic discovered in what is now Germany. What’s interesting about this little critter is that it doesn’t show signs of feathers.

Many sites are reporting on this newly announced dinosaur discovery, including:

National Geographic, Scaly New Dinosaur Creates Flap Over Feathers’ Evolution
The Age (AU), New dinosaur fossil ruffles a few feathers
Scientific American, Scaly Dino Find Complicates Feather Evolution

The researchers published their findings in Nature. You can read the first paragraph of A new carnivorous dinosaur from the Late Jurassic Solnhofen archipelago and see the pictures/figures. Of course, for full access check your library!

The name Juravenator refers to the Jura Mountains of Bavaria where the fossil was found, and starki refers to the Stark family that owns the fossil-bearing limestone quarry. It was discovered about 10 years ago, but took many years to prepare because of the extremely hard limestone encasing the fossil. It had been nicknamed Borsti in German, a name commonly given to bristle-haired dogs, on the assumption the creature was endowed with bristly protofeathers.

Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Saurischia
Infraorder: Coelurosauria
Family: Coeluridae
Genus: Juravenator

A new species of fish called Paedocypris progenetica, has been discovered in highly acidic peat swamps on the Indonesian island of Sumatra. The new species belongs to the carp family and is possibly the world’s smallest vertebrate animal with females maturing at 7.9 mm.

‘This is one of the strangest fish that I’ve seen in my whole career’, said Ralf Britz, zoologist at the Natural History Museum in London who helped analyze the skeleton and pelvic fin structure of the fish. ‘It’s tiny, it lives in acid and it has these bizarre grasping fins. I hope we’ll have time to find out more about them before their habitat disappears completely.’

The new fish was discovered by fish experts Maurice Kottelat (from Switzerland) and Tan Heok Hui from the Raffles Museum of Biodiversity Research in Singapore, while working with their colleagues from Indonesia and with Kai-Erik Witte from the Max Planck Institute in Germany.

P. progenetica is so tiny that researchers initially thought they were baby fish until someone noticed the females were carrying eggs. The tiny, see-through fish also has a reduced head skeleton, which leaves the brain unprotected by bone. They live in dark tea-colored waters with an acidity of pH3, which is at least 100 times more acidic than rainwater. These swamps were once thought to harbour very few animals, but recent research has revealed that they are highly diverse and home to many species that occur nowhere else. The peat swamps were damaged by large forest fires in 1997 and are threatened by logging, urbanization and agriculture. Several populations of Paedocypris have already been lost.

Although announcement of this new species claims it to be the world’s smallest fish, the Australian Museum Fish Site has a fun article that tells of 2 other contenders to the title of ‘World’s Smallest Fish’.

Hungry for more information? Check out budak’s Blog with lots more pictures and discussion. Also, the researchers’ report was published in the British journal, Proceedings of the Royal Society B. You can read the abstract but for full access you’ll need to check it out from a library that subscribes to the journal: Paedocypris, a new genus of Southeast Asian cyprinid fish with a remarkable sexual dimorphism, comprises the world’s smallest vertebrate.

Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae