. Bulletin of the British Museum (Natural History) Entomology. THEREVINE STILETTO-FLIES OF THE ETHIOPIAN REGION 305 lobe well-developed. Hypandrium present as a narrow sclerite between the ventral basal part of gonocoxites. Aedeagus simple; phallic part comparatively long, narrow and curved in lateral view; in dorsal view several times wider proximally than distally. Dorsal apodeme in dorsal view never narrower than proximal part of phallus. Ejaculatory apodeme simple. Tergite 8 constricted in middle, but less so in the turneri-group. Sternite 8 of rather variable shape. Remarks. Eleven specie
. Bulletin of the British Museum (Natural History) Entomology. THEREVINE STILETTO-FLIES OF THE ETHIOPIAN REGION 305 lobe well-developed. Hypandrium present as a narrow sclerite between the ventral basal part of gonocoxites. Aedeagus simple; phallic part comparatively long, narrow and curved in lateral view; in dorsal view several times wider proximally than distally. Dorsal apodeme in dorsal view never narrower than proximal part of phallus. Ejaculatory apodeme simple. Tergite 8 constricted in middle, but less so in the turneri-group. Sternite 8 of rather variable shape. Remarks. Eleven species of Thereva are known to occur in Africa south of the Sahara. The genus seems to be restricted to the continental part of the Ethiopian region, as no representatives are so far known from Madagascar or from other islands belonging to the region. This fact indicates either that the genus is a relatively recent evolutionary group, or that it has penetrated into the Ethiopian region from a comparatively recent date, or both. A great many species from all zoogeographical regions have been described into Thereva, but future research will certainly show that Thereva in a strictly mono- phyletic sense is primarily a Holarctic group, with many species in the Nearctic and Palaearctic regions. Based on a study of the type spi • ies, plebeja, and of many other European species, the following synapomorphic characters can be listed: face always strongly pilose; head low and wide, the distance between lower corner of eyes usually longer than height of head; female frons usually with one or two polished black calli, the callus rarely secondarily covered with tomentum; a relatively high number (4-5) of notopleural setae; pile present on all the pleura,. 360 358 Figs 357-360. Thereva turneri-group, 357, 358, female heads in frontal view; 359-360, antennae. 357, T. curticornis; 358, T. globulicornis; 359, T. curticornis, Q; 360, T. globulicornis, <$ holotype. Scale: 0-5 Please no
Size: 1920px × 1302px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbritishmuseumnaturalhistory, bookcentury1900, bookcoll
