Eoagnostus

Eoagnostus is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the terminal Lower Cambrian (Toyonian), until the earliest Middle Cambrian (earliest Kounamkites-zone, part of the lower Amgaian).[1]

Eoagnostus
Temporal range: terminal Toyonian to early Amgaian (Nephrolenellus multinodus-zone, Ovatoryctocara granulata-zone, earliest Kounamkites-zone)
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Scientific classification
Kingdom:
Animalia
Phylum:
Arthropoda
Class:
Trilobita
Order:
Agnostida
Suborder:
Agnostina
Superfamily:
Agnostoidea
Family:
Peronopsidae
Genus:
Eoagnostus

Resser and Howell, 1938
species
  • E. roddyi Resser and Howell, 1938 (Type)
  • E. acrorhachis Rasetti and Theokritoff, 1967[1]

Distribution
  • E. roddyi terminal Lower Cambrian of the United States (Bonnia-zone, Kinzers Shale, Lancaster, New York; Pennsylvania; Vermont)[2] and the early Middle Cambrian of Newfoundland, and Greenland (around the boundary of Ovatoryctocara-zone, Henson Gletscher Formation).[1]
  • E. acrorhachis occurs in the terminal Lower Cambrian of the United States (Bonnia-zone, Hatch Hill, New York).[2]

Description

Almost identical to Archaeagnostus, but the frontal lobe of the central raised area of the cephalon (or glabella) is effaced, while the back of glabella is inflated.[1]

References
  1. Naimark, E.B. (2012). "Hundred species of the Genus Peronopsis Hawle et Corda, 1847". Paleontological Journal. 46 (9): 945–1057. doi:10.1134/S0031030112090018. S2CID 85130465.
  2. Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997


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