Eoagnostus

Eoagnostus Temporal range: terminal Toyonian to early Amgaian (Nephrolenellus multinodus-zone, Ovatoryctocara granulata-zone, earliest Kounamkites-zone) PreꞒ Ꞓ O S D C P T J K Pg N ↓
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	†Trilobita (?)
Order:	†Agnostida
Family:	†Peronopsidae
Genus:	†Eoagnostus Resser and Howell, 1938
Species[1]
Eoagnostus roddyi Resser and Howell, 1938 (type) Eoagnostus acrorhachis Rasetti and Theokritoff, 1967

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]

Distribution

• Eoagnostus 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]
• Eoagnostus 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. Bibcode:2012PalJ...46..945N. 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