Bioacoustics of Copiphora brevicauda

Note: A comparison of the type specimens of C. brevicauda , along with a series of specimens from Venezuela and Ecuador , with those collected in Costa Rica , reveals small but consistent difference between the two populations. The differences relate mostly to the size of the stridulatory file and the number of stridulatory teeth, along with minor differences in the shape of the fastigium of vertex and coloration. Because I have sound recordings of only the Costa Rican individuals of the species, it is impossible to say to what extent these morphological differences are reflected in the acoustic properties of the calling behavior, and whether the two populations are reproductively isolated (although, based purely on the fact that physical properties of the stridulatory file in Tettigoniidae are strongly correlated with the physical properties of the sound, such differences undoubtedly exist). Therefore, it seems more advisable at this time to acknowledge these differences by giving the Costa Rican population a subspecific status, instead of elevating them to a full species.

Diagnostic description.— Body of medium size as for the genus, with wings in both sexes extending well beyond apex of abdomen. Fastigium of vertex forming relatively small horn, usually conical, but sometimes with ventral keel slightly expanded and not narrowing gradually towards apex; fastigium 2.5 times as long as eye diameter; dorsal part of fastigium granulose. Face convex; genal carinae of head well developed, granulose. Pronotum smooth, flat dorsally; anterior dorsal margin straight, posterior one straight to weakly convex; lateral lobe of pronotum 1.8 times longer than high. Male stridulatory file nearly straight, 1.7-2.7 mm long, 150-200 μm wide, with 154-214 teeth ( Figs. 42 D-E); mirror approximately rectangular; vein AA 1 very thick, small, parallel vein next to AA 1 present. Ventral spines of femora relatively short and thin; all genicular lobes armed with sharp spines, sometimes spine on anterior lobes of fore femora obtuse. Male cercus thick, blunt, and somewhat incurved, distinctly constricted below apex; ventral, subapical spine of cercus long and thin; apex of cercus with sharply triangular lobe underneath ( Fig. 7 I). Male subgenital plate narrowed toward apex, apex weakly emarginated; styli short, about 2.5 times as long as wide. Female subgenital plate approximately triangular, with distinct, triangular apical incision. Ovipositor long, straight, 1.6-2.1 times as long as hind femur. Coloration .— General coloration light green. Fastigium of vertex yellow; face bright yellow, sometimes with 2, 4 or 6 small black dots; clypeus, labrum and mandibles black; occiput and genae green. Pronotum green; tegmina green, occasionally mottled with few, small brownish dots; male stridulatory file green; legs green, with blue femoral spines (green or yellow in poorly preserved specimens); hind femora usually with well developed reticulate pattern on their outer surfaces. Abdominal terga green, sterna yellow; in live individuals abdominal spiracles surrounded by blue circles.

Diagnostic description.— Fastigium of vertex forming relatively small horn, with well developed ventral keel, keel often slightly expanded subapically ( Fig. 8 F). Stridulatory file 2.7 mm long, with 154 teeth, teeth in distal half of file distinctly thicker and less densely distributed ( Fig. 42 F). Ovipositor relatively short compared to other members of the genus, ratio ovipositor/hind femur 1.9-2.1 ( Fig. 8 H). Tegmina never mottled with brown dots. Measurements .— Table 4 . Bioacoustics.— C. brevicauda costaricensis produce low duty, relatively high Q calls, consisting of irregular series of long chirps. Individual series of chirps last about 2.6 s (at 25°C) and are produced after intervals of several minutes of silence. Each series has 5-7 chirps, with each chirp lasting 185.3-269.1 ms (n=7), and consisting of 8-13 individual pulses. Most energy of the call is allocated between 9.2 and 11.8 kHz.