Niobrara Aquarium

Lately I've taken a break from drawing dinosaurs and have focused more on modern animals as well as what naturalist Nigel Marven dubbed "the co-stars" of the prehistoric world. This two-page spread focuses on large fish known from Kansas' Niobrara Formation, which 87 to 82 million years ago was submerged beneath a shallow sea. The fish here were drawn to scale with one another, with one inch used for one meter. To give you an idea of their size, the smallest -- Enchodus -- was 1.5 meters (5 feet) long.

1) Cretoxyrhina mantelli

2) Xiphactinus audax

3) Scapanorhynchus rhaphiodon

4) Pachyrhizodus caninus 

5) Enchodus petrosus

6) Bonnerichthys gladius

7) Saurodon leanus

8) Protosphyraena perniciosa

9) Ptychodus mortoni

Ironically, I found Cretoxyrhina the hardest to re-create. Sharks are not only deceptively difficult to draw and while this particular species belonged to the same order of sharks as the great white, I didn't want it to be a Jaws clone. Add to that the fact that only shark teeth fossilize (as the rest of their skeletons are made of cartilage) and many clashing artistic depictions for comparison, and you have a very hard creature to capture on the page.

Choosing color schemes for these animals was also quite difficult, since none of these species were likely reef-dwellers, yet I didn't want them all to be blue or gray. Both Scapanorhynchus and Ptychodus I made brown -- the former to stay obscured in the deep waters where it may have hunted, the latter for camouflaging itself along the seafloor in order to avoid mosasaurs. Enchodus is actually related to modern salmon, so I gave it similar markings (though with goldenrod and reddish brown instead of olive green and bright pink). Bonnerichthys has no close living relatives, but since it was a filter-feeder I based its colors on a photo of basking shark with marbled markings.