Rhinocarcinosoma

Rhinocarcinosoma
Temporal range: Late Silurian, 427.4–419.2 Ma
Fossil carapace and portions of the abdomen of R. vaningeni
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Order: Eurypterida
Superfamily: Carcinosomatoidea
Family: Carcinosomatidae
Genus: Rhinocarcinosoma
Novojilov, 1962
Type species
Rhinocarcinosoma vaningeni
(Clarke & Ruedemann, 1912)
Species
  • R. cicerops (Clarke, 1907)
  • R. dosonensis Braddy, Selden & Doan Nhat, 2002
  • R. vaningeni (Clarke & Ruedemann, 1912)
Synonyms
  • Eurypterus? cicerops Clarke, 1907
  • Eusarcus? cicerops (Clarke, 1907)
  • Eusarcus vaningeni Clarke & Ruedemann, 1912

Rhinocarcinosoma is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of Rhinocarcinosoma have been discovered in deposits ranging of Late Silurian age in the United States, Canada and Vietnam. The genus contains three species, the American R. cicerops and R. vaningeni and the Vietnamese R. dosonensis. The generic name is derived from the related genus Carcinosoma, and the Greek ῥινός (rhinós, "nose"), referring to the unusual shovel-shaped protrusion on the front of the carapace (head plate) of Rhinocarcinosoma, its most distinctive feature.

Other than the protrusion, Rhinocarcinosoma was anatomically very similar to its close relative, Eusarcana, though it lacked the scorpion-like telson (the posteriormost division of the body) of that genus. Further distinguishing features include more slender appendages and slightly different ornamentation of scales. In terms of size, Rhinocarcinosoma was a medium-sized carcinosomatid eurypterid, with the largest species, R. vaningeni, reaching lengths of 39 centimetres (15.4 in).

In contrast to other carcinosomatids, Rhinocarcinosoma is not known only from marine settings, but also from deposits that were once lakes or rivers. It was adapted to a bottom-dwelling lifestyle, as either a burrowing or digging scavenger or top predator, feeding on other invertebrates and small fish.