Two species of Barychelidae, Psalisto s venadensis and Trichopelma laselva, are described from Costa Rica . These are the first records Of this mygalomorph family from this country . Both species were associated with tropical wet forests .
Four new species are described from Costa Rica and Panama. Metriopelma zebrata Banks is redescribed, its female being new to science. Cyclosternum fasciatus, new combination, is discussed. M. morosus Banks is reduced to synonymy of M. zebrata. An English Appendiz with keys, diagnosis and explaination to figures is included.
Seven species of Sericopelma and 3 of Brachypelma are described as
new and Brachypelma mesomelas (O.P. Cambridge), is redescribed and
discussed. All diagnosis and key in English.
Thirteen species of theraphosid spiders ("tarantulas") are described as
new. Sphaerobothria hoffmani and Aphonopelma seemannz are redescribed and the
male 01" S. seemanni is described for the first time . It is argued that the genera
discussed here, which are traditionally placed in separa te subfamilies (Grammostolinae
and Isehnocolinae) should be grouped . Common features to these
genera are the shape of the bulb (distally atenuated and curved ventrally),
spermatheea divided in two portions by a deep noteh, and coxa 1 with anterior
side covered by conic spinules. The feature formerly used to separa te the two
groups is not consistent within genera.
Keys, diagnosis and explanations to figures are included in an English
Aphonopelma burica, Aphonopelma crinirufum, Aphonopelma sclerothrix, Aphonopelma xanthochromum, Brachypelma albopilosum, Sericopelma angustum, Brachypelma fossorium, Lasiodora brevibulba, Lasiodora carinata, Lasiodora icecu, Lasiodora rubitarsa, Lasiodora puriscal, Stichoplastoris denticulatus, Stichoplastoris elusinus, Stichoplastoris obelix