Biology:Eoagnostus

Short description: Extinct genus of trilobites

Eoagnostus Temporal range: terminal Toyonian to early Amgaian (Nephrolenellus multinodus-zone, Ovatoryctocara granulata-zone, earliest Kounamkites-zone) PreЄ Є O S D C P T J K Pg N ↓
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

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).

Distribution

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

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.

References

Wikidata ☰ Q5381577 entry