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
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Scientific 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.
References
edit- Walter C. Sweet, 1964. Nautiloidea -Oncocerida; Treatise on Invertebrate Paleontology, Part K. (K295). Geological Society of America and University of Kansas Press.