Bioacoustics of Eulioptera atypica

Diagnosis . A small Eulioptera , characterized by atypical opaque tegmina, as in Phaneroptera ; however, the stridulatory file is typical for the genus Eulioptera . Male description . Color. Yellow-green, with brown spots on pronotum, legs and abdominal tergites. Cerci dark tipped. Small species. Head typical of the genus, eyes round prominent, fastigium of vertex compressed, just raised at the apex, narrower than scapus, not contiguous with fastigium of frons. Antennae long. Pronotum without lateral carinae, anteriorly just incurved, posteriorly widely rounded, longer than high. Both pairs of wings well-developed. Tegmina about 5.7 times longer than broad, rounded at tips. Veins and veinlets not much contrasting to remaining parts of tegmina. Hind wings with green archedictyon, extending beyond tegmina by a bit less than one third of latter. Stridulatory area on the left tegmen long and reticulate, mirror on the right tegmen oval ( Fig. 25 ). Stridulatory file under the left tegmen arched, about 1.2 mm long, consisting of many small teeth very close ( Fig. 26 ). Legs. Fore coxae armed, fore femora unarmed, fore tibiae furrowed dorsally, with 4 spines + 1 apical inner and outer spur on ventral margins and 1 apical spur on dorsal outer margin, open tympana on both sides. Mid femora unarmed, mid tibiae with 6-7 spines on both ventral margins + 1 spur on each ventral side and on inner dorsal side. Hind femora unarmed, hind tibiae with sparse hairs and 8-9 rows of spines on ventral margins, many spines on dorsal margins + 3 spurs on each apical side. Abdomen. Supra-anal plate transverse with a little rounded posterior margin. Cerci longer than the subgenital plate, apically much incurved with a pointed brown concave tip ( Fig. 27 ). Subgenital plate triangular, basally larger than apically, narrowing about in the middle, with a v-shaped apex, two rounded short lobes, and a central longitudinal carina; styli absent ( Fig. 27 ). Female . Unknown.

Discussion . The present specimen was found within a series of Phaneroptera sparsa , a very common species in tropical Africa, but it appeared different mainly by the structure of its subgenital plate (see Fig. 27 ). Its tegmina are opaque, as in Phaneroptera species; however, when the specimen was mounted with the left tegmen open, it was possible to inspect also the stridulatory file under the tegmen, which resulted very atypical for the genus Phaneroptera ( Fig. 26 ). The subgenital plate is apically bilobed, as in some species of the genus Eulioptera , but also of Phaneroptera (see above P. abdita n. sp. ). In all examined species of Phaneroptera the male stridulatory file has a double bending in the middle or the distal part, and the stridulatory teeth have their steep side pointing basally, indicating sound production during wing opening. The lack of this steep side may result in a completely different kind of song during wing opening. Thus, it seems justified to describe this new taxon within the genus Eulioptera . Among the species of this genus, only E. flexilima Ragge, 1980 from South Africa , Mozambique and Zimbabwe has a similar subgenital plate, but their cerci and the stridulatory file are differently shaped (cf. Ragge 1980 ); in addition, E. atypica n. sp. has opaque tegmina, while E. flexilima has shiny, translucent tegmina.