Ellisites, an Upper Ordovician Heliolitid coral intermediate between Coccoserids and Proporids

The Upper Ordovician heliolitid corals Ellisites labechioides gen. et sp. nov. and E. astomata (Flower) combine vesicular skeletal plates with zones of strongly dilated vertical trabeculae. In these characters they provide the first evidence of a phylogenetic link between the Coccoseridicae and Proporicae. They are referred to a new family, the Ellisitidae, and included in the Coccoseridicae, which necessitates taxonomic modification of the latter to include genera with vesicular skeletal plates. They show features most related to Coccoseris Eichwald, 1855, and to two of three species considered to have been erroneously referred to the stromatoporoid Dermatostroma Parks, 1910. Their substantially vesicular skeletal development can lead them to be mistaken for strongly cystose labechiid stromatoporoids.