Rugosans immured in Silurian Paleofavosites; Brassfield Formation (Llandovery) of Ohio

摘要: The occurrence of a solitary rugose coral, Streptelasma sp., anchored within colonial skeleton the tabulate coral Paleofavosites prolificus is here reported. Numerous specimens were found three coralla this species among 55 collected from uppermost 30 cm Lower Silurian (Llandovery) Brassfield Formation at Fairborn, Ohio. These rugosans are largely immured in favositid coralla, and, as bioclaustrations, reveal important information on paleobiology both species. However, immuring some was not complete during life rugosan, calice openings these present corallum surface. Complete immuration (or total overgrowth) indicates that rugosan no longer competed successfully for space; whether entombment occurred after death or cause its unknown. Streptelasma, assuming an epibiotic lifestyle probably benefited secure attachment to larger, stable form and able exist particular facies interpreted have been vigorous, current-swept environment. high energy environments would inimical small, light-weight living isolated corallites. successful settling growth colonies reflects their higher status aggression hierarchy. This interspecies interaction early Paleozoic development hierarchy corals belonging Rugosa Tabulata (Phylum Cnidaria).