Three new monospecific genera are described from montane areas of Cost
a Rica. Like the other three known Costa Rican rhytidochrotine genera
(Hylopedetes Rehn, 1929, Scirtopaon Descamps & Rowell, 1984 and Microp
aon Descamps & Rowell, 1984) they belong to the atympanate and apterou
s division of the subfamily. All are apparently confined to small geog
raphical areas. Exerythracris is volcanica n.sp. is a fern eater from
the light, gaps and edges of montane forest, and resembles in gross mo
rphology the similarly specialised Hylopedetes. It is the most norther
ly representative of the subfamily so far described, extending almost
to the Costa Rican/Nicaraguan border. Brackeracris varablancensis n.sp
. is found in successional areas (landslips, anthropogenically altered
habitats) in montane forest; its diet is unknown, but does not appare
ntly include ferns; morphologically it is closest to Scirtopaon. Talam
ancacris palustris n.sp. is confined to a few relict subalpine swamps
and appears to eat Asteraceae preferentially; it is not obviously clos
ely allied to the other genera. Additionally, new morphological, ecolo
gical and biogeographic data are given for the three previously descri
bed genera.