NEW ACTINOPTERYGIAN FISH FROM THE NAMURIAN MANSE BURN FORMATION OF BEARSDEN, SCOTLAND

Four new species of actinopterygians are described from the Manse Burn Formation (Namurian) of Bearsden, Glasgow, Scotland. Two fusiform spe cies are members of, and a third is questionably assigned to, Mesopoma : M. carricki, M. ? smithsoni, and M. pancheni. A new gibbose species is assigned to a new genus, Frederichthys musadentatus. Mesopoma is re viewed and rediagnosed, and its relationships to Frederichtys are exam ined with regard to a recent analysis of early actinopterygian (palaeo niscid) phylogeny, Mesopoma is a member of a probably paraphyletic gro up within a polytomous stem-group actinopteran radiation. An alternati ve phylogeny places Mesopoma on the common stem-group of the Haplolepi dae, Aeduellidae, and Redfieldiformes. Frederichthys is closely relate d to the platysomids. Otoliths preserved within the mesopomid material are described and compared with those of other osteichthyans; the pre sence of three pairs of otoliths as a teleostome characteristic is que stioned.