The Mesozoic families Microsolenidae, Latomeandridae, Synastreidae and Cunnolitidae basically differ from the Recent fungiids, with which they had traditionally been classified due to their having synapticulae and porous septa. We propose a new suborder Microsolenina for these families because their members possess collar-like structures (pennulae of Gill 1967) spaced along the trabeculae, tending to merge into more or less continuous flanges parallel to the septal distal margin, distributed on each face of the septa. The fungiids, having trabeculae with granulations set off from the trabecular axis towards interseptal space (vepreculae of Jell 1974), are closest to the faviids from which they probably derived.

Key words: Anthozoa, Scleractinia, Fungiina, Microsolenina, microstructure, pennulae, Mesozoic, Eocene, Recent.