1980] 
Young — Ecology of Cicadas 
183 
cicadas having very soft calls. Zammara tympanum adults are heard 
throughout most of the year and sometimes during the dry season 
and they call from the moss and other epiphyte-covered trunks of 
forest trees primarily along the river-edge. This cicada is mottled 
green and brown and has brown spots on the wings, immediately 
distinguishing it from the others. The call is a “winding up-like 
pulsating buzz. Adults when calling occur at one per tree, and there 
are usually no more than two or three calling males present within 
approximately 800m 2 parcels of river-edge forest during an optimal 
calling period. Males call throughout the day, including overcast 
and light drizzle conditions. Males are bright green with brown 
markings while females are drab olive green and brown. 
Fidicina sericans, both sexes, are black with green markings on 
the thorax and smoky wings. The call is a steady rather high-pitched 
buzz most frequently heard during sunny weather and during the 
dry season. Sometimes several males congregate in the same tree, 
particularly if it is along an edge of forest, and sometimes, under 
these conditions, several adjacent exposed trees may have males 
calling at the same time. The calling males are seen perched on the 
upper portions of the trunk and on branches, and they are easily 
spotted on light-colored bark species such as Pourouma and 
Cecropia. Adult densities, as indicated by calling males, probably 
are about 1-20 cicadas per 800m 2 of forest during a period of peak 
calling, although this may be an underestimate since only a fraction 
of males may chorus at any one time. Calling males are heard 
primarily on the forest slope and less so at the bottom of the ravine 
and at the very top. 
Fidicina n.sp., both sexes, possesses a green head and thorax and 
black and orange-banded abdomen, sometimes with patches of 
silvery hairs laterally. Of all of the cicadas in Costa Rica, this species 
is the most difficult one to catch because of their habit to perch very 
high in trees and to change trees after one call. Based on compari- 
sons with type materials and other specimens, this is most likely a 
new species. It has a very distinctive two-part call: the first part is a 
series of pulsating chirps followed by a longer period of siren-like 
and pulsating calls. Unlike this species, both Z. tympanum and F. 
sericans, as well as the other species to be discussed, often make 
repeated complete calls from the same perch, even if interspersed 
with periods of silence lasting several minutes or an hour or two. F. 
n.sp. is heard during the dry season and it occurs in the ravine and 
