Early Cretaceous genus extinctions

Machimosaurus is an extinct genus of machimosaurid crocodyliform from the Late Jurassic (Kimmeridgian and Tithonian) and Early Cretaceous. The type species, Machimosaurus hugii, was found in Switzerland. Other fossils have been found in England, France, Germany, Portugal, Switzerland and Tunisia. Machimosaurus rex is the largest named teleosauroid and thalattosuchian, with an estimated length of up to (skull length ). Machimosaurus is the largest known crocodyliform of the Jurassic.

Saccocoma is an extinct genus of crinoids that lived from the Late Jurassic to the Early Cretaceous in Europe and North America. It contains at least two species.

thumb|250 px|Abrytusites julianyi (Honnorat-Bastide), Upper Hauterivian, [[Palilula, Bulgaria, (Coll. G. Mandov) at the Sofia University Museum of Paleontology and Historical Geology]]

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.

Pentasteria is an extinct genus of sea star that lived from the Early Jurassic to the Early Cretaceous. Its fossils have been found in Europe.

Aspidoceras is an extinct ammonoid cephalopod genus belonging to the family Aspidoceratidae.

Paramacellodus is an extinct genus of scincomorph lizards from the Early Cretaceous of England and France, and the Late Jurassic of Portugal and the western United States. The type species, Paramacellodus oweni, was named in 1967 from the earliest Cretaceous (Berriasian) Purbeck Group in Dorset, England. Additional material referable to a species of Paramacellodus, possibly P. oweni, has been described from the Morrison Formation, specifically in Como Bluff, Wyoming, and Dinosaur National Monument, Utah. An indeterminate species is known from the Berriasian aged Angeac-Charente bonebed in Fran

Berriasella is a discoidal evolute perisphinctacean ammonite, and type genus for the neocomitid subfamily Berriasellinae. Its ribbing is distinct, consisting of both simple and bifurcated ribs that extend from the umbilical seam across the venter; its whorl section generally compressed, the venter more or less narrowly rounded. The species Berriasella jacobi traditionally has been regarded an index fossil defining the base of the Cretaceous, however since 2016 this had been replaced by the first occurrence of Calpionella alpina. Some authors regard B. jacobi as instead belonging to the genus S

Plegiocidaris is an extinct genus of echinoids that lived from the Triassic to the Early Cretaceous. Its remains have been found in Asia and Europe. It was named by the paleontologist Auguste Pomel.

Lisboasaurus is a small (400 mm length) genus of Mesozoic crocodylomorph that lived in fresh water. It is known from fossilized tooth and jaw fragments of Late Jurassic and Early Cretaceous age. Two species have been described. In the past Lisboasaurus has been interpreted as an avialan, troodontid, or an anguimorph lizard. Both species are currently assigned to Crocodylomorpha, one is reassigned to the genus Lusitanisuchus.

Cylindroteuthis is a genus of belemnite that lived from the Early Jurassic to the Early Cretaceous. Its fossils have been found in Asia, Europe, North America, and New Zealand.