Atychodracon

Post author:Adam S. Smith
Post published:22/07/2018
Post category:Genus page Plesiosauria Pliosauroidea Rhomaleosauridae

Holotype specimen of Atychodracon megacephalus in the Bristol City Museum and Art Gallery (from Swinton, 1948). The specimen was destroyed during the Second World War.

The genus Atychodracon was erected by Smith (2015) to accommodate 'Rhomaleosaurus' megacephalus, because it is generically separarate from Rhomaleosaurus sensu stricto (Smith and Dyke 2008). A. megacephalus is closely related to Eurycleidus and some authors have regarded A. megacephalus as a distinct species of Eurycleidus. Three dimensional scan with texture (colour) removed…

Attenborosaurus

Post author:Adam S. Smith
Post published:22/07/2018
Post category:Attenborosaurus Genus page Plesiosauria Pliosauridae Pliosauroidea

Photograph of the holotype of Attenborosaurus, before it was destroyed. The skeleton was mounted in a block together with a cast of the opposite side of the body and the opposite side of the head (from Swinton, 1949)

Attenborosaurus is an unusual plesiosaur because it combines a long neck with a relatively large head. It is classified as a pliosaur in some classifications, but some phylogenies place it in a more basal position. The genus was introduced for 'Plesiosaurus' conybeari, a species originally described by Sollas (1881). Bob Bakker coined…

Aristonectes

Post author:Adam S. Smith
Post published:22/07/2018
Post category:Aristonectinae Elasmosauridae Genus page Plesiosauria Plesiosauroidea

Skull of Aristonectes in various aspects. From Gasparini et al. (2003).

The mysterious plesiosaur Aristonectes is notable for its mouthful of pin-like teeth. A special feeding guild, the 'trap guild', has been proposed to accommodate Aristonectes and other plesiosaurs with similar dentition (Chatterjee and Small 1989) such as Cryptoclidus, Kimmerosaurus, and Kaiwhekea. These plesiosaurs may have fed in a similar manner to the…

Apractocleidus

Post author:Adam S. Smith
Post published:22/07/2018
Post category:Cryptoclididae Genus page Plesiosauria Plesiosauroidea

Cryptoclidus (the type specimen of 'Apractocleidus', V.1091, with the tail of V.1104 and a replica head) in the Hunterian Museum, Glasgow, Scotland. Photo by Adam S. Smith. 2007.

The genus and species 'Apractocleidus teretipes' was erected by Smellie (1916). Smellie (1915) provided a preliminary account of the specimen before he named it. The specimen is now regarded as an old-adult individual of Cryptoclidus. The taxon 'Apractocleidus' is therefore considered a junior synonym of Cryptoclidus. The specimen was collected by Alfred…

Albertonectes

Post author:Adam S. Smith
Post published:22/07/2018
Post category:Elasmosauridae Genus page Plesiosauria Plesiosauroidea

Albertonectes is a very long-necked elasmosaurid from the Late Cretaceous of Alberta, Canada. The holotype specimen (TMP 2007.0110001) consists of an almost complete skeleton lacking a skull (Kubo et al. 2012). The neck contains 76 cervical vertebrae, which is a unique character of Albertonectes vanderveldei and the highest number of neck vertebrae…

Archaeonectrus

Post author:Adam S. Smith
Post published:21/07/2018
Post category:Genus page Plesiosauria Pliosauroidea Rhomaleosauridae

Archaeonectrus illustration (From Novozhilov 1964)

The genus Archaeonectrus was proposed by Novozhilov (1964) for 'Plesiosaurus' rostratus, a species named by Owen (1865). By modern standards, Owen's (1865) original description is rather inadequate. One notable characteristic of Archaeonectrus rostratus is the relatively small size of the limbs relative to its body. It has been classified as a pliosauroid,…