Triarthrus is a genus of Upper Ordovician ptychopariid trilobite found in New York, Ohio, Kentucky, and Indiana, eastern and northern Canada, China and Scandinavia. It is the last of the Olenid trilobites, a group which flourished in the Cambrian period. The specimens of T. eatoni that are found in the Beecher's Trilobite Bed, Rome, New York area are exquisitely preserved showing soft body parts in iron pyrite. Pyrite preservation has given scientists a rare opportunity to examine the gills, walking legs, antennae, digestive systems, and eggs of trilobites, which are rarely preserved. Triarthr
Triarthrus is a genus of Upper Ordovician ptychopariid trilobite found in New York, Ohio, Kentucky, and Indiana, eastern and northern Canada, China and Scandinavia. It is the last of the Olenid trilobites, a group which flourished in the Cambrian period. The specimens of T. eatoni that are found in the Beecher's Trilobite Bed, Rome, New York area are exquisitely preserved showing soft body parts in iron pyrite. Pyrite preservation has given scientists a rare opportunity to examine the gills, walking legs, antennae, digestive systems, and eggs of trilobites, which are rarely preserved. Triarthrus is therefore commonly used in science texts to illustrate trilobite anatomy and physiology.
== Distribution == T. beckii Upper Caradoc and Ashgill, Snake Hill Formation, Cohoes, New York State; and Kentucky. T. billingsi Ashgill?, Quebec T. canadensis is known from the Upper Ordovician of Canada (Katian, lower Member of the Whitby Formation, Craigleith vicinity, Georgian Bay area; middle Member of the Whitby Formation, Whitby, Rogue River and Pickering, all Lake Simcoe area, Ontario) T. eatoni Upper Caradoc-Ashgill, N.Y., is known from the Upper Ordovician of Canada (Ashgill, lower Member of the Whitby Formation, Craigleith vicinity, Georgian Bay area, Lake Simcoe area, Ontario; and Quebec) and the United States (New York) T. glaber Ashgill, Quebec T. huguesensis Ashgill, Quebec T. latissimus Sweden T. linnarssoni Norway and Sweden T. rougensis Ashgill, Ontario T. sichuansis China T. spinosus is known from the Upper Ordovician of Canada (Katian, middle Member of the Whitby Formation, Rogue River and Pickering, both Lake Simcoe area, Ontario and Quebec), and the United States (New York). T. novoaustralis is known from Upper Ordovician of Australia (middle Katian, Malachis Hill Formation)
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).