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| Shuvuuia: what's so great about a pair of arms? |
Meaning: desert bird
Time: Late Cretaceous, c 75 million years ago
Place: Mongolia
Size: about 60 centimetres (23.6 inches) long
Type of Dinosaur: parvicursorine alvarezsaurid (single-clawed bird-like dinosaur)
Shuvuuia is an odd little dinosaur, part of a group initially thought to be flightless birds. These fuzzy creatures had long, narrow snouts and tiny teeth and a single claw on their extremely shortened arms. A common idea is that they would have used their claws to open insect nests and then snarfed them up; sort of dinosaurian anteaters. Here, one Shuvuuia is preening another.
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| Deinocheirus: why stop at just a pair of arms? |
Meaning: peculiar terrible hand
Time: Late Cretaceous, c 72 million years ago
Place: Mongolia
Size: about 11 metres (36 feet) long and 6.3 tonnes (6.9 tons)
Type of Dinosaur: deinocheirid ornithomimosaur (weirdo ostrich dinosaur)
For many years, Deinocheirus was one of the great mysteries of palaeontology. A pair of powerfully-clawed forelimbs, 2.4 metres (7.9 feet) long, and nothing else. What were they from? Was it a carnosaur far larger than any other, opening up sauropods like tins of sardines? Was it one of those odd ground sloth-like therizinosaurs? The arms are actually very much like the ostrich dinosaurs' - perhaps it's one of those?
Turns out that the last one was right, but Deinocheirus wasn't just a big and bulky Struthiomimus, not at all. In 2014, complete skeletons of this mysterious monster finally were revealed to the world, and Deinocheirus was more bizarre than anyone imagined. Huge and bulky, with a towering hump on its back, a spoonbill, and a very deep lower jaw. Stomach contents preserve fish and gastroliths, showing an omnivorous diet. Wild, wild stuff.
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| A fine feathery face on a small forest herbivore. |
Meaning: [geologist George] Louderback's agile reptile
Time: Middle Jurassic, c 168 million years ago
Place: southwest China
Size: about 1.2 metres (3.9 feet) long, but the known specimen may be a juvenile
Type of Dinosaur: neornithischian genasaur (primitive-advanced beaked dinosaur)
Agilisaurus louderbacki, like many dinosaurs, is only known from a single specimen. Fortunately, though, it's a very good one with virtually all the bones represented. It's a small beaked herbivore, and remains from Russia show that at least some of these dinosaurs had feathery coverings on their bodies, so I've restored Agilisaurus with such integument here.
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| Desert sky, dream beneath a desert sky, rivers run but soon run dry... |
Meaning: San Juan [County, New Mexico, where it was discovered] Ojo Alamo [Formation] reptile
Time: Late Cretaceous, c 66 million years ago
Place: Texas, New Mexico, Utah; probably Wyoming and Mexico as well
Size: complete specimens about 20 metres long (66 feet) and 16 tonnes (17.6 tons) are subadult; fragmentary remains generally considered to be from Alamosaurus suggest sizes of 30 metres (98 feet) and more than 50 tonnes (55 tons)
Type of Dinosaur: opisthocoelocaudiine saltasaurid (column-handed advanced armoured long-necked dinosaur)
The only sauropod currently known from Late Cretaceous North America, Alamosaurus is undoubtedly one of the best animals ever. It lived right at the end of the Age of Reptiles, alongside T. rex, and grew to be one of the biggest land animals. More and more remains of this giant seem to be cropping up in recent years, and hopefully more will reveal what their growth and lifestyle was like.
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| There's something FISHY about little Liaoningosaurus... |
Meaning: paradoxical Liaoning [Province, where it was discovered] reptile
Time: Early Cretaceous, c 122 million years ago
Place: northeast China
Size: 34 centimetres (13.4 inches) long; whether the described specimen is an adult or not is debated
Type of Dinosaur: ankylosaurid ankylosaur (armoured dinosaur)
Recently, Liaoningosaurus has gotten some attention as a new study suggests it was semiaquatic and fed on fish, as evidenced by fish remains in its stomach, and that the described specimen (apparently, many, many other ones are known) is actually a grown adult! These claims have understandably drawn criticism, and apparently the paper does not do a terrific job of making its case. However, I don't think we should readily dismiss these claims - it honestly seems like a very plausible niche for an ankylosaur to occupy, and as more fossils are described they'll help us understand just what the natural history of this odd little armoured dinosaur was...
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