Opallionectes is a large, around 5 m long, derived cryptoclidid plesiosauroid from the Early Cretaceous of South Australia. It is known from a partial opalised skeleton, which is mounted for display in the South Australian Museum. The holotype specimen lacks a skull. It is diagnosed by the following unique combination of characters:…
Umoonasaurus is a small (~2.5 m long) leptocleidid that lived during the Early Cretaceous in Southern Australia. The holotype specimen (AM F99374), a spectacular opalised skeleton including the skull, is nicknamed 'Eric'. It is the most complete opalised plesiosaur skeleton (and fossil vertebrate) known. It was originally described briefly as Leptocleidus sp.…
In summer 2023 a plesiosaur skeleton was offered at auction by Sotheby's that may have looked familiar. This notable specimen is the 'Blockley Plesiosaur', originally offered at auction by Sotheby's in 2010. This is a potentially significant specimen so I'm flagging it up to briefly discuss the provenance, history, and taxonomic identity…
Nakonanectes is a small elasmosaurid plesiosaur from the Bearpaw Shale of Montana, USA. It is known from a single moderately complete specimen including a particularly fine skull. It has a relatively short neck for an elasmosaur consisting of 'only' 39-42 neck vertebrae. However, 16–19 of the neck vertebrae were lost in a…
Sachs (2004) regarded 'Woolungasaurus' as a junior synonym of Styxosaurus and assigned the type species ('W. glendowerensis') to that genus under the new combination 'Styxosaurus glendoweresnis'. However, this placement was unsupported by unambiguous apomorphic characters (Kear 2007). Since 'Woolungasaurus' has no unique diagnostic characters, Kear (2005) reassigned all specimens of it to…
The name Vectocleidus was erected by Benson et al. (2012b) for a leptocleidid from the Early Cretaceous of the Isle of Wight, UK. The type specimen was previously referred to Leptocleidus sp. Vectocleidus can be confidently identified as a leptocleidid but its position within the clade is unstable (Benson et al. (2012b).…
