Genus Avalonnectes Benson, Evans & Druckenmiller, 2012
Type species: Avalonnectes arturi Benson, Evans & Druckenmiller, 2012
Diagnosis: Small-bodied basal rhomaleosaurid (trunk length =735 mm) with 18–19 dorsal vertebrae, a low, autapomorphic number (from Benson et al. 2012).
Distribution: Lower Jurassic, Hettangian, Europe (United Kingdom).
Avalonnectes arturi Benson, Evans & Druckenmiller, 2012
Holotype: NHMUK 14550, posterior portion of the skull, and incomplete articulated postcranial skeleton.
Referred specimen: AGT uncatalogued, incomplete postcranial skeleton.
Stratum typicum: Blue Lias Formation, Pre-planorbis beds, earliest Hettangian, Lower Jurassic.
Locus typicus: Street, Somerset, England.
Diagnosis: As for the genus.
Comments: Avalonnectes arturi is one of the earliest known rhomaleosaurids. The postcranial skeleton of the holotype specimen (NHMUK 14550) is exhibited in the Marine Reptiles Gallery of the Natural History Museum in London. The holotype preserves 23 cervical vertebrae, but the atlas-axis complex is missing. Thus, the minimum cervical vertebral count is 25. To date, only a brief osteological description, provided by Benson et al. (2012), is available.
Systematic palaeontology (sensu Benson & Druckenmiller 2014)
Plesiosauria de Blainville, 1835
Rhomaleosauridae Kuhn, 1961
Institutional abbreviations
AGT – Alfred Gillett Trust, Street, United Kingdom
NHMUK – Natural History Museum, London, United Kingdom
Image courtesy
The image of the skull and the interpretations of the skull and postcranium are taken from Benson et al. (2012). They are distributed under a Creative Commons Attribution 2.5 Generic license.
Cited literature
de Blainville, H. M. D. (1835) Description de quelques espèces de reptiles de la Californie, précédée de l’analyse d’une système générale d’Erpetologie et d’Amphibiologie. Nouvelles Archives du Muséum d’Histoire Naturelle. 4, 233–296.
Kuhn, O. (1961) Die Familien der Rezenten und fossilen Amphibien und Reptilien. Verlagshaus Meisenbach, Bamberg. 79 pp.
