Tetrameroceras is a genus of short, essentially straight, breviconic, nautiloid cephalopods from the middle and Upper Silurian of Europe and North America included in the oncocerid family Hemiphragmoceraidae.

Tetrameroceras
Temporal range: Middle -Late Silurian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloidea
Order: Oncocerida
Family: Hemiphragmoceratidae
Genus: Tetrameroceras
Hyatt, 1884

The body chamber is inflated, dorsal and ventral profiles both convex. Aperture contracted and visored with a long ventral hyponomic sinus, 2 pairs of shorter dorsolateral sinuses, and a short dorsal salient branching from the peristome. The siphuncle has continuous actinosiphonate deposits.

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