Hydrocephalus (trilobite)

Hydrocephalus Temporal range: Middle Cambrian PreЄ Є O S D C P T J K Pg N
Hydrocephalus carens at the National Museum (Prague)
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Trilobita
Order:	Redlichiida
Suborder:	Redlichiina
Family:	Paradoxididae
Genus:	Hydrocephalus Barrande, 1846
species
H. carens Barrande, 1846 (type) H. lyelli (Barrande, 1852) = Rejkocephalus lyelli H. mandiki Kordule, 1990 H. minor (Boeck, 1827) = Trilobites minor H. paradoxum (Hawle et Corda, 1847) = Paradoxides paradoxum H. rotundatus (Barrande, 1846) = Paradoxides rotundatus, Rejkocephalus rotundatus H. vikensis Rushton & Weidner, 2007[1]
Synonyms
Phlysacium Hawle et Corda, 1847 Rejkocephalus Kordule, 1990

Hydrocephalus ("water head") is an extinct genus of redlichiid trilobite that was very common during the Middle Cambrian of Eurasia and North America, which lasted from 508 to 497 million years ago. This trilobite is up to 20 cm long and more widely built than others of the time. In comparison to other members of its family, its glabella appears swollen.

Gallery

• 
  Hydrocephalus minor from Jince (Czech Republic)
• 
  Free cheek of H. carens, 33mm between the tips

References

1. Rushton, A.W.A.; Weidner, T. (2007). "The Middle Cambrian paradoxidid trilobite Hydrocephalus from Jämtland, central Sweden" (PDF). Acta Geologica Polonica. 57 (4): 391–401. Retrieved 30 March 2013.