Coniacian genus first appearances

Ichthyodectes is an extinct genus of ichthyodectid ray-finned fish which lived during the Late Cretaceous. Fossils of the species included have been found from Canada to Texas.

Tusoteuthis is an extinct genus of large enchoteuthine cephalopod that lived during the Cretaceous. Although often called a squid, it is now thought to be more closely related to modern octopuses. Although many specimens from the Western Interior Seaway of North America were described, at 2019, only one, poorly preserved specimen from Kansas is recognized as Tusoteuthis. One species, T. longa, is traditionally recognized. In 2019, due to the poor preservation of the holotype specimen, Tusoteuthis was considered likely to be a nomen dubium, and it was proposed that later described species are b

Madtsoia is an extinct genus of madtsoiid snakes. It is known from the Eocene of Argentina (M. bai), the Paleocene of Brazil (M. camposi), the Late Cretaceous (Maastrichtian) of India (M. pisdurensis), and the Late Cretaceous (Maastrichtian) of Madagascar (M. madagascariensis). The type species (M. bai) was the largest with an estimated length of , and the other three species were smaller. A long M. madagascariensis would have weighed , but an isolated specimen suggests that this species reached in maximum length. Juvenile Madtsoia madagascariensis may have eaten a wide array of small vertebra

Bonnerichthys is a genus of fossil fishes within the family Pachycormidae that lived during the Coniacian to Maastrichtian stage of the Late Cretaceous. Fossil remains of this taxon were first described from the Smoky Hill Member of the Niobrara Chalk Formation of Kansas (Late Coniacian-Early Campanian), and additional material was later reported from the Pierre Shale, Mooreville Chalk, Demopolis Chalk, Wenonah Formation, and Moreno Formation, among other localities. It has also been reported in European Russia, specifically from the Rybushka Formation of the Saratov Region. It grew to at leas

Plesioplatecarpus is an extinct genus of plioplatecarpine mosasaur known from the Late Cretaceous (middle Coniacian to middle Santonian stage) of the northern Gulf of Mexico and the Western Interior Basin of North America.