#gillicus

[ildarotyrannus]

Reconstruction of Xiphactinus audax from 2021. Yes, that was the time when I drew a fish. This large (up to 5-6 meters) actinopterygian fish was previously known as Porteus molossus. Its characteristic feature is the forward-thrust lower jaw, which gives a resemblance to a bulldog. Several Xiphactinus specimens have been preserved with the ingested prey inside (in one case 4,2 m. individual swallowed 1,9 m. Gillicus). They could have died because of the resistance of the victims, which led to ruptures of internal organs. Done with ballpoint pen, colored pencils and watercolors.

[veloci-raptor]

A Day in Niobrara

1. Hesperornis regalis 2. Nyctosaurus gracilis 3. Pteranodon longiceps 4. Claosaurus agilis 5. Niobrarasaurus coleii 6. Gillicus arcuantus 7. Enchodus petrosus 8. Platecarpus tympaniticus 9. Dolichorhynchops osborni 10. Protostega gigas 11. Clidastes prophython 12. Tylosaurus proriger 13. Bonnerichthys gladius 14. Ptychodus mortoni 15. Styxosaurus snowii 16. Xiphactinus audax 17. Cretoxyrhina mantelli

[actual-haise]

The recently described mosasaur Gnathomortis shortly before using it's eponymous jaws to chomp down on a Gillicus.

[palaeopedia]

The Gillicus (1875)

Phylum : Chordata Class : Actinopterygii Superorder : Osteoglossomorpha Order : Ichthyodectiformes Family : Ichthyodectidae Subfamily : Ichthyodectinae Genus : Gillicus Species : G. arcuatus

Late Cretaceous (100 - 66 Ma)

2 m long and 100 kg (size)

Western interior seaway, North America (map)

Gillicus arcuatus was a relatively small, 2-metre long ichthyodectid fish that lived in the Western Interior Seaway, in what is now central North America, during the Late Cretaceous. Like its larger relative, Ichthyodectes ctenodon, G. arcuatus had numerous small teeth lining its jaws, and ate smaller fish by sucking them into its mouth. Gillicus would also filter feed and were also eaten by their own relative, Xiphactinus. In particular, one 4.0 m fossil specimen was collected by George F. Sternberg with another, nearly perfectly preserved 1.8 m long ichthyodectid Gillicus arcuatus, inside of it. The larger fish apparently died soon after eating its prey, most likely due to the smaller fish prey struggling and rupturing an organ as it was being swallowed. This fossil can be seen at the Sternberg Museum of Natural History in Hays, Kansas.