Hațeg Island Residents

At the end of the Cretaceous period, Hațeg Island in modern Romania was home to one of the strangest animal communities known to science: With a few exceptions (including one very big one), most of the animals here were miniature versions of creatures from the mainland. I had long wanted to visit this island through my art, as well as do another two-page, multi-species spread like my Niobrara Aquarium piece (see the last post of September 2015). Here, then, is the result:

1) Rhabdodon priscus
2) Struthiosaurus transylvanicus
3) Telmatosaurus transsylvanicus (note the extra "s"; don't ask me why)
4) Allodaposuchus precedens
5) Bradycmene draculae (yup)
6) Magyarosaurus dacus
7) "Hatzegopteryx" thambena (I use the parentheses because some scientists regard the genus as synonymous with Quetzalcoatlus)
8) Zalmoxes robustus
9) Balaur bondoc

The two smallest animals here, Struthiosaurus and Bradycmene, were both about two meters (six and a half feet) long.

Choosing color schemes for the three largest dwarf dinosaurs (the largest of which was 20 feet long) was a challenge, but I ultimately opted to give both rhabdodonts spots (based on an earlier hand drawing I did of Muttaburrasaurus, now classified as a rhabdodont by some) and to give Telmatosaurus a striped tail, just as skin impressions of North American hadrosaurs seem to suggest. So as not obscure Magyarosaurus' osteoderms, I made the animal a solid, bluish-green.

Balaur is reconstructed according to the hypothesis that it was a flightless, paravian theropod rather than a dromaeosaur, hence the shorter skull (the real one still hasn't been found). As for the star of this spread, Hatzegopteryx, I worked off the idea that azhdarchid pterosaurs were more like storks than vultures, opting for river game over carrion. With that in mind, I based loosely based its body colors on the saddle-billed stork of sub-Saharan Africa, while I based the crest and beak coloration off of the wrinkled hornbill of Southeast Asia.

I'm hoping that image of a giant pterosaur towering over much smaller dinosaurs (plus Allodaposuchus) will take people who view this piece off-guard and that their eyes will linger on this beast. The other eight, I'll admit, are drawn rather small and perhaps under-rendered, but given their size in life and the crudeness of some of their fossils, that's sort of the point.

Backyard Endangered Species

The bulk of the endangered mammals I've been drawing in the past year come from Africa or Asia, while chances are that most the people who read this blog will come from either the United States or Europe. These latter regions, however, do have their own imperiled species as well.

Black-footed ferret (Mustela nigripes)
Current Range: Pockets of Canada, Mexico, and the western United States
Conservation Status: Endangered (c. 1,200 as of Fall 2013)

This mustelid used to be the primary predator of prairie dogs, but went into severe decline during the 1800s and 1900s due to fur-trapping and the culling of their main prey.

Mediterranean monk seal (Monachus monachus)
Current Range: Pockets of the Mediterranean and mid-Atlantic, including Madeira, the coast of Croatia, and the Aegean Sea
Conservation Status: Endangered (less than 700 as of 2015)

The world's rarest seal, this backyard beast was hunted extensively as early as the days of the Roman Empire, and in more recent times has been killed by fishermen who regard them as pests.

Baird's tapir (Tapirus bairdii)
Current Range: Central and South America, from the Yucatán Peninsula to western Colombia)
Conservation Status: Endangered (less than 5,000 as of 2008)

While much further from American or European readers than the other two species in this post (outside of zoos, of course), the Baird's tapir still inhabits a wide though sparsely-populated area. And though much smaller than an elephant or even the smallest rhino species, this bizarre animal is the largest mammal indigenous to Central America.

Season of the Titanosaur

 
While Brontosaurus, Diplodocus, and Brachiosaurus were the dominant sauropods in the dinosaur books I grew up reading (along with Supersaurus and the more dubious Seismosaurus and Ultrasauros) titanosaurs have gradually been eclipsing these Jurassic giants in both size estimates and public exposure. They prove that sauropods were still going strong during the Late Cretaceous and that the largest species were by no means limited to the Morrison Formation.

This sea change began in 1993 with the description of Argentinosaurus. Though known only from a handful of bones, they clearly hinted at a truly awe-inspiring sauropod. Expeditions in Patagonia continued to churn out titanosaurs weighing around or above 50 tons and approaching 100 feet in length: Puertasaurus, Futalognkosaurus, Dreadnoughtus, and most recently, Notocolossus. These giants weren't limited to Argentina either: In 2001, American paleontologists described Paralititan, a titanosaur around the same size as Argentinosaurus and which lived alongside Spinosaurus and Carcharodontosaurus, two of the largest-known meat-eating dinosaurs. Other giants of lesser renown include Bruhathkayosaurus from India, Ruyangosaurus from China, Sauroposeidon and Alamosaurus from the southwestern United States (the former initially believed to be a brachiosaur and the latter originally believed to have been smaller), "Angloposeidon" from England, and an unnamed titanosaur from Australia known unofficially as "Cooper".

Last month not only saw the debut of Notocolossus, but also the mounting of a titanosaur skeletal mount at the American Museum of Natural History in New York. Yet another Argentine animal, this one measures over 120 feet long and is estimated to have weighed around 70 tons, making it the current leading candidate for the largest dinosaur. This display will be up until January of 2020, and as a new exhibit in the country's leading natural history museum, seems to me like a crowning moment for titanosaurs.

While I'm much happier with this titanosaur drawing than the one I did of Futalognkosaurus a year and a half ago (see top of the post), I still had trouble capturing the (rear) right leg, which still looks a bit out-of-place. Like "Cooper", this titanosaur still lacks a proper name, though I've seen the name "Flechasaurus" applied to it given the bones' proximity to the town of La Flecha in Chubut. This dinosaur probably wasn't synonymous with any of the aforementioned Patagonian titanosaurs, due to differences in sediment age and its discovery in a different province from the others.

Africa's Jurassic Park

Though Spinosaurus has a superstar among dinosaurs (thanks, in part to Jurassic Park III and Paul Sereno's aquatic restoration of this animal proposed in 2014), few other dinosaurs from this continent receive half as much exposure. About a decade before Ernst Stromer described this bizarre theropod, however, other German paleontologists like Eberhard Fraas and Werner Janensch uncovered a host of amazing new dinosaurs from the Tendaguru Formation in Tanzania (then the colony of German East Africa). The largest of these was Giraffatitan, known as "Brachiosaurus brancai" until the 2000s. Its skeleton at the Museum fur Natürkunde in Berlin stands over 40 feet high and remains the most complete of any large brachiosaur.

Despite the sheer size of this sauropod, Kentrosaurus is easily the Tendaguru Formation's stand-out dinosaur. It was smaller but thornier cousin of Stegosaurus, and according to a 2011 study by Heinrich Mallison, a single swipe of the tail would have been more than enough to crack open a human skull. Like many other dinosaurs, Kentrosaurus is believed to have had a much thicker tail than previously thought (thanks to a 2010 paper by Phil Currie and W. Scott Parsons). In addition to the animal's rear anatomy as a whole, this drawing is intended to reflect that idea, as well as the discovery of small osteoderms in other stegosaurs.

One of Kentrosaurus' contemporaries was Dicraeosaurus, an oddity among Late Jurassic sauropods in that A) it was less than 50 feet long, B) it had an unusually short neck and C) an strangely high spine. To emphasize this latter feature, I gave my Dicraeosaurus bright markings along its back, drawing inspiration from the Malagasy rainbow frog (albeit without the blue). Since the skull of the Berlin mount is quite obviously a plastic cast based on Diplodocus, I chose to draw this copy rather than reconstruct the actual head.

Theropods are also known from the Tendaguru Formation, including the early spinosaur Ostafrikasaurus and the carcharodontosaur Veterupristisaurus. Since neither is known from a good skeleton yet, however, I chose to portray an equally mysterious theropod from the site.

Like Dicraeosaurus, Elaphrosaurus is also mounted at the Museum für Naturkunde as a half-bone, half-cast skeleton. Growing up, it was also portrayed as an early, carnivorous ancestor to the toothless ornithomimosaurs. In recent years, however, paleontologists have come to regard it as a ceratosaur -- possibly a large relative of the short-armed, ostrich-like Limusaurus. which was running around China about this time. My sketch of Elaphrosaurus is meant to wed this idea with the museum's current mount, implying that the animal was a long-legged herbivorous theropod rather than the dinosaur equivalent of the cheetah. 

Crazy Arms

When I was boy, one of the greatest mysteries about dinosaurs for me was "who owned the biggest arms of all time?". This question revolved around not one, but two theropod dinosaurs from Late Cretaceous Mongolia: Deinocheirus and Therizinosaurus. For decades, both were known from nothing but a pair of menacing arms, each measuring about eight feet long. Each seemed to belong to jumbo-sized killer theropod, dwarfing and capable of ripping a T. rex to pieces.

Then, in 2001, the Discovery Channel program When Dinosaurs Roamed America aired, and I (along with countless other paleofans, I'm sure) was introduced to a therizinosaur for the first time in the form of Nothronychus. It was a herbivore North American predecessor to its family's namesake that, in the words of narrator John Goodman, "[looked] like a half-plucked turkey and [walked] like a potbellied bear". While it mostly used its arms pull down high branches, Nothronychus at one point used them to smack down an attacking dromaeosaur. Though we have few Therizinosaurus fossils outside of its arms, the image of these dinosaurs as the archosaur version of ground sloths has been cemented by the discovery of other therizinosaurs (particularly the much earlier Beipiaosaurus and Alxasaurus), as well as the portrayal of these animals in subsequent paleo docudramas like Chasing by Dinosaurs: The Giant Claw (featuring Therizinosaurus meeting Nigel Marven) and Planet Dinosaur (featuring Nothronychus again).

And what about Deinocheirus? This contemporary of Therizinosaurus turned out to be stranger still: Paleontologists had long suspected that it was an overgrown ornithomimosaur, based on the similar arms and claws (which were too blunt to be instruments of death). Based on two headless specimens in storage at a Mongolian museum and a skull smuggled into Europe, Deinocheirus a bulky, hump-backed herbivore with a head more like a hadrosaur than an ornithomimosaur. Like Therizinosaurus, it too was a colossal plant-eating theropod that was probably covered in feathers.

While both probably confronted Tarbosaurus, a close cousin to T. rex known from the same bone bed as each, I do wonder if they ever competed for same leaves and branches with one another, indirectly as a species or directly (and perhaps violently) as individuals.

Tylosaurus' Troublesome Tummy

While non-avian dinosaurs were my gateway to science and remain my favorite prehistoric creatures, I've developed an appreciation for other extinct animal groups, including ichthyosaurs, mammoths, terror birds, and notosuchians. Lately, I've been fascinated by mosasaurs, and not just thanks to Jurassic World. While I grew up with images of green, ridge-backed leviathans that tussled with serpentine plesiosaurs and snatched pterosaurs from the sky, I'm much more intrigued with mosasaurs as depicted now, in light of recent discoveries about their tail anatomy (which now includes a sickle-shaped tail), skin color (which in some was black on top and white on bottom), and birthing methods (live underwater birth, like ichthyosaurs, plesiosaurs, and cetaceans).

With that in mind, I set out to depict the largest, most famous -- er, the most famous mosasaur after Mosasaurus, Tylosaurus.

While sketching the beasts' skull was no cakewalk, the thing that gave me the most trouble was capturing the underside of the mosasaur in the flesh. The skeletal mount I used looked fantastic, peering down on visitors like Smaug over Bilbo Baggins in the second Hobbit film; in retrospect, however, Tylosaurus may not have been flexible enough to assume this undulating pose. This made capturing the animal's tummy a nightmare, with constant erasures and redrawing of borders.

In the end, I settled with the boundaries established in the draft on the left, and tried to make the proximity of each body segment as clear as possible with different degrees of shading, but I still feel the drawing could have been much better if I had gotten the underside right.

2015 in Mesozoic Paleontology

To cap off the year, I recently did another paneled, less serious drawing, this time celebrating the new (and old, in one case) Mesozoic fauna described this year:

January: Nundasuchus, a Early Triassic archosaur from Tanzania (hence the safari sign).

February: Ichthyosaurus anningae, a new species of Ichthyosaurus. Uncovered by Mary Anning, but was long mistaken for a plaster cast.

March: Metoposaurus algarvensis, a new species of the amphibian Metoposaurus from Early Triassic Portugal.

April: Brontosaurus, a re-established genus long considered synonymous with Apatosaurus.
May: Yi, a bat-winged, feathered theropod from Late Jurassic China.

June: Regaliceratops, a chasmosaurine ceratopsian from Late Cretaceous Alberta.

July: Wendiceratops, a centrosaurine ceratopsian from Late Cretaceous Alberta.

August: Gueragama, a mid-Cretaceous lizard from Brazil closely related to modern iguanas.

September: Ugrunaaluk, a Late Cretaceous hadrosaur from Alaska. The northmost non-avian dinosaur ever discovered.

October: Spinolestes, an Early Cretaceous mammal from Spain preserved with quill-like hair imprints.

November: Dakotaraptor, a Late Cretaceous dromaeosaur from South Dakota. Lived alongside Tyrannosaurus and Triceratops.
 
December: Kunbarrasaurus, an Early Cretaceous ankylosaur from Australia (hence the aurora australis).