Abstract. Articulated holaspid specimens of Placoparia Hawle and Corda, 1847 Eoharpes Raymond, 1905 entombed inside cephalopod conchs under the remains large illaenid, asaphid, cyclopygid dalmanitid trilobites from Middle Ordovician Šárka Formation Prague Basin (Czech Republic) are described discussed. Two such samples were also found in overlying Dobrotivá Middle/Late age. Four articulated juv...

Abstract Zygocycloides ? foerstei n. sp. is described from the Llandovery (Aeronian) Brassfield Formation of southwestern Ohio. This among oldest reported Silurian cyclocystoids North America and only American cyclocystoid that preserved with a complete rim marginal ossicles. Smith Paul, 1982 most similar to Nicholsodiscus Glass et al., 2003 (Katian) Perforocycloides Ewin 2019 (Llandovery, Tely...