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.