Akanthomyces ampullifer, A. aranearum, A. novoguineensis and a new spe
cies A. ovalongatus are described from dead spiders in Taiwan. Akantho
myces ovalongatus is characterized by its globose to subglobose conidi
ogenous cells that have an abruptly narrowed neck, and obovoid, oblong
to ellipsoidal conidia. In these features, A. ovalongatus resembles A
. aranearum, A. arachnophilus and A. novoguineensis, but it can be rea
dily separated from these species either by roughness of conidiogenous
cells, or by morphological characters of conidia. A key to the thirte
en known species of Akanthomyces is provided.