Middle Jurassic genus first appearances

Hypsocormus (from , 'height' and 'timber log') is an extinct genus of pachycormid fish from the Middle to Late Jurassic of Europe. Fossils have been found in Germany, France and the UK.

Hsisosuchus is an extinct genus of crocodyliform from China. Currently there are three species within this genus: H. dashanpuensis is from the Middle Jurassic, while H. chungkingensis and H. chowi are from the Late Jurassic. It is likely to have been a medium-sized (~ long) predator. thumb|left|Skull and [[vertebrae of H. chungkingensis at the Hong Kong Science Museum]] Fossils of H. chungkingensis were found in the Shangshaximiao Formation (near Chongqing city). The holotype consists of the cranial skeleton and caudal osteoderms. A more complete specimen was found and des

Kosmoceras is a moderately evolute ammonite genus from the upper Callovian (Middle Jurassic) of Europe with a simple aperture and irregular ribbing interrupted by an irregular row of lateral tubercles. Strong ventral tubercles are separated by a smooth depression running along the rim.

Hemicidaris is an extinct genus of echinoids that lived from the Middle Jurassic to the Early Cretaceous. Its remains have been found in Africa, Asia, and Europe.

left|thumb|Holotype of G. leedsi, NHMUK PV R3540 thumb Gracilineustes is an extinct genus of marine crocodyliform that lived in the oceans during the Middle to Late Jurassic. Gracilineustes was a carnivore that spent much, if not all, its life out at sea. It was a small reptile, with G. leedsi measuring long and G. acutus measuring long. thumb|Skull and limb of G. leedsi ==Discovery and species== Fossil specimens referrable to Gracilineustes are known from Middle-Late Jurassic deposits of England and France.

Belemnotheutis is an extinct coleoid cephalopod genus from the middle and upper Jurassic, related to but morphologically distinct from belemnites. Belemnotheutis fossils are some of the best preserved among coleoids. Remains of soft tissue are well-documented in some specimens, even down to microscopic muscle tissue. In 2008, a group of paleontologists even recovered viable ink from ink sacs found in several specimens.

Betelgeusia is an extinct genus of sea stars in the family Radiasteridae. It was described by Blake and Reid, in 1998, and existed in what is now the Netherlands, Texas, United States, Morocco, and India, during the Middle Jurassic through the Cretaceous period. It contains the species B. brezinai, B. exposita, B. riedi, and B. orientalis.