Genera considered junior synonyms of
Geosaurus include
Brachytaenius and
Halilimnosaurus . Numerous species had been assigned to this genus since the 19th Century. However,
phylogenetic analyses begun in 2005 did not support the
monophyly of
Geosaurus. Although some traditional species, such as
G. suevicus and
G. araucanensis formed a
natural group,
Enaliosuchus is also within that group. This, as well as further study showing that traditional metriorhynchid genera were not grouped based on actual relationships, necessitated almost all traditional species being removed from
Geosaurus and reclassified elsewhere, as well as several species previously placed in other genera to be reclassified as species of
Geosaurus. •
Geosaurus grandis, first described by Wagner in 1858, was formerly considered a species of
Cricosaurus. It is known from a complete skull. •
Geosaurus lapparenti is known from south-east France and dates to the early Cretaceous period (
Valanginian). It was named in honour of
French palaeontologist
Albert-Félix de Lapparent, and is based upon isolated skull and post-cranial bones (neck and tail vertebrae and a partial pelvic girdle) from the Early Cretaceous (Valanginian) of France. It was originally classified as a species of
Dakosaurus. A large species of
Geosaurus is known only from a single tooth from the
Nusplingen Plattenkalk of
Germany. }}
Reclassified species In 2009, Young and de Andrade published a re-description of
Geosaurus, examining its relationships and the validity of species lumped into the genus. After performing a phylogenetic analysis of metriorhynchids, they found that many species were grouped in a
paraphyletic manner or with the wrong genera. Specifically, they found that several species formerly classified as
Geosaurus, including
G. suevicus,
G. saltillense,
G. vignaudi, and
G. araucanensis were actually examples of the related
Cricosaurus.
Geosaurus carpenteri, also formerly referred to
Dakosaurus, is known from a partial skull. Teeth identical to the known teeth of this species are also known from
Yorkshire, UK. It was assigned to its own genus,
Torvoneustes by Andrade
et al., 2010. An unnamed specimen classified as
Geosaurus was found in the
Oxfordian Jagua Formation of Cuba, though further study has shown this species to be more closely related to
Cricosaurus as well. == Palaeobiology ==