A skeleton of Alligatorellus has also been found in the Solnhofen Limestone of Kelheim, Germany. The limestone was deposited in a marine environment and the individual may have washed into a lagoon where it was fossilized. Remains of four crinoids that lived in the lagoon are found in the same block as the skeleton. The skeleton includes osteoderms and limb bones, which are three-dimensionally preserved. The German skeleton shows more details of atoposaurid anatomy than most fossils, as other atoposaurid remains are compressed flat.
Temporal range: Late Jurassic
|Alligatorellus beaumonti in the Royal Belgian Institute of Natural Sciences.|
Aegyptosuchidae is an extinct family of eusuchian crocodyliforms from the Cretaceous period of Africa. They are characterized by their large size and flat heads. The family includes two genera, Aegyptosuchus and Aegisuchus.Alligatorium
Alligatorium is an extinct genus of atoposaurid crocodylomorph from Late Jurassic marine deposits in France.Amphicotylus
Amphicotylus is an extinct genus of goniopholidid mesoeucrocodylian from the Tithonian of Colorado and Oklahoma.Anthracosuchus
Anthracosuchus (meaning "coal crocodile" in Greek) is an extinct genus of dyrosaurid crocodyliform from the Paleocene of Colombia. Remains of Anthracosuchus balrogus, the only known species, come from the Cerrejón Formation in the Cerrejón mine, and include four fossil specimens with partial skulls. Anthracosuchus differs from other dyrosaurids in having an extremely short (brevirostrine) snout, widely spaced eye sockets with bony protuberances around them, and osteoderms that are smooth and thick. It is one of the most basal dyrosaurids along with Chenanisuchus and Cerrejonisuchus. The species name is a reference to the Balrog, a creature in J. R. R. Tolkien's fantasy novel The Lord of the Rings that could, like the remains of Anthracosuchus, be found in a mine.Atoposauridae
Atoposauridae is a family of crocodile-line archosaurs belonging to Neosuchia. The majority of the family are known from Late Jurassic to Early Cretaceous marine deposits in France, Portugal, and Bavaria in southern Germany. The discovery of the genus Aprosuchus, however, extends the duration of the lineage to the end of the Cretaceous in Romania.Atoposaurus
Atoposaurus is an extinct genus of crocodylomorph. It is the type genus of the family Atoposauridae. Fossils have been found that were Late Jurassic in age from two distinct species in France and Germany.
One interesting feature of Atoposaurus is that it lacked dorsal scutes, a common characteristic of atoposaurids as well as most crurotarsans. The absence of scutes, along with its relatively small size (specimens reach lengths of up to 17 cm), narrow supratemporal fossae, wide occipital region, thin postorbital bar, and smooth ornamentation, has led some paleontologists to believe that it is perhaps a juvenile form of another genus within Atoposauridae, most likely Alligatorellus.Brillanceausuchus
Brillanceausuchus is an extinct genus of atoposaurid crocodylomorph. Fossils have been found in Early Cretaceous–age rocks of Cameroon. The genus is notable for the position of the secondary choana within its palate. Parts of the pterygoid bones make up the rostral margin of the choana and thus separate it from the palatines, a feature also seen in the more advanced neosuchian suborder Eusuchia. This characteristic was once thought to be characteristic of Eusuchia, but its presence in Brillanceausuchus suggests that the trait is homoplasic, thus making the evolution of the position of the choana within crocodilians more complex than previously thought.Coelosuchus
Coelosuchus is an extinct genus of goniopholidid mesoeucrocodylian. Fossils have been found from the Graneros Shale of the Benton Group in Wyoming, and are of Cenomanian age. It was slightly over 1 meter in length.Eusuchia
The Eusuchia ("true crocodiles") are a clade of crocodylomorphs that first appears in the Early Cretaceous with Hylaeochampsa. Along with Dyrosauridae and Sebecosuchia, they were the only crocodyliformes who survived the K-T extinction. Since the other two clades died out 35 and 11 million years ago, all living crocodilian species are eusuchians, as are many extinct forms.Karatausuchus
Karatausuchus is an extinct genus of atoposaurid crocodylomorph. It is known from a single specimen discovered in the Late Jurassic (Oxfordian - Kimmeridgian) Karabastau Svita from the vicinity of Mikhailovka in the Karatau Mountains of southern Kazakhstan. The type specimen is PIN 25858/1, a complete but poorly preserved juvenile skeleton with some possible soft tissue preservation. It is notable for having over 90 teeth, but its other anatomical details are difficult to discern. The length of this individual is estimated at 160 millimetres (6.3 in). Karatausuchus was described in 1976 by Mikhail Efimov, and the type species is K. sharovi.Khoratosuchus
Khoratosuchus is an extinct genus of neosuchian crocodylomorph which existed in northeast Thailand during the early Cretaceous period. Its type species is Khoratosuchus jintasakuli. Khoratosuchus is the youngest and most advanced Mesozoic crocodyliform yet known from Thailand. It possesses several distinctive features that help determine its phylogenetic position among crocodylomorphs, including secondary choanae relatively posterior and almost encircled by the pterygoid bones on the palate and a smooth dorsal surface of the skull.Laganosuchus
Laganosuchus is an extinct genus of stomatosuchid crocodyliform. Fossils have been found from Niger and Morocco and date back to the Upper Cretaceous.Montsecosuchus
Montsecosuchus is an extinct genus of atoposaurid crocodylomorphs. It is the replacement generic name for Alligatorium depereti, which was described in 1915 from the Montsec Lithographic Limestone quarry of Spain. Fossils found from this locality are from the Early Cretaceous, being Upper Berriasian-Lower Valanginian in age. While many publications concerning atoposaurids after 1915 have included mentions of A. depereti, none has offered a redescription or revision of the species, though some recognized that great differences existed between it and other members of the genus. In these publications, the skull of A. depereti was shorter in relation to body length than any other species of Alligatorium (being less than half of the presacral length), and this may have been evidence for the genetic distinction of the species, although no replacement name was proposed. However, better preparation of the holotype specimen MGB 512, a nearly complete articulated skeleton embedded in a limestone matrix now housed in the Museu de Ciències Naturals de Barcelona, allowed for a revision of the species in 1990 in which the name Montsecosuchus was first used.
Montsecosuchus differs in several ways from other atoposaurids such as Alligatorium, Alligatorellus, and Theriosuchus. Several characteristics of the skull including the presence of an ungrooved parietal-squamosal suture and a caudally projecting retroarticular process distinguish Montsecosuchus from these genera. Both Montsecosuchus and Alligatorellus possess three sacral vertebrae; this may be a shared synapomorphy of the two genera. The shortness of the radius is an autapomorphy of the genus that is not seen in any other atoposaurid, although it is common in more derived crocodylomorphs.Nannosuchus
Nannosuchus (meaning "dwarf crocodile") is an extinct genus of goniopholidid mesoeucrocodylian from the Berriasian of England.Neosuchia
Neosuchia is a clade within Mesoeucrocodylia that includes all modern extant crocodilians and their closest fossil relatives. It is defined as the most inclusive clade containing all crocodylomorphs more closely related to Crocodylus niloticus (the Nile Crocodile) than to Notosuchus terrestris. Neosuchia is very diverse and may be polyphyletic, as the clade has undergone many revisions since it was first named in 1988. Neosuchians first appear in the Early Jurassic with the earliest known goniopholid Calsoyasuchus, which lived during the Sinemurian and Pliensbachian stages.Shamosuchus
Shamosuchus is an extinct genus of neosuchian crocodile that lived during the Late Cretaceous (Santonian-Campanian) period in what is now the Gobi desert of Mongolia, approximately 85 to 74 million years ago.Symptosuchus
Symptosuchus is an extinct genus of goniopholidid mesoeucrocodylian. It is known from the Late Cretaceous of Argentina. Argentine paleontologist Florentino Ameghino named the genus in 1899, along with the type species S. contortidens. It was formally described by Carlos Rusconi in 1934.Wahasuchus
Wahasuchus is a genus of extinct mesoeucrocodylian of the Middle Campanian age found in the Quseir Formation, Egypt. The generic name derives from the Arabic word واحة (waha), which means "oasis", and souchos from the Greek in honor of crocodile-headed god of ancient Egypt. The specific egyptensis (Lat.) means from Egypt.Fossils of skull and jaw fragments, dorsal vertebrae, and fragmentary appendicular remains have been recovered.