Oedosphenella Frey 1936

Field: Agricultural and Biological Sciences (Life Sciences)

Oedosphenella Frey 1936: 93 Frey 1936: 93; Munro 1957: 47; Merz 1992: 226; Norrbom et al. 1999: 177. Type species: Tephritis canariensis Macquart 1843 (by monotypy). Bevismyia Munro 1957: 48; Cogan & Munro 1980: 544; Norrbom et al. 1999: 105, new synonym. Type species: Bevismyia basuto Munro 1957 (by original designation). Diagnosis. The genus Oedosphenella can be separated from other genera of Tephritidae by the following combination of characters. Head with two pairs of frontal setae and two pairs of reclinate orbital setae, the anterior acuminate, the posterior lanceolate. Postocular setae a mixture of black reclinate and white lanceolate. Frons with some white setulae in the middle. Two pairs of well-developed scutellar setae present. Scutellum either strongly convex and shiny or at most slightly convex and dull. Posterior notopleural setae black. Katepisternal setae black. Lower calypter as wide as upper. Wing with a short but broad extension of cell cup, vein R 4+5 bare or at most with 1–3 setae on the node. Hind femur anteroventrally with a row of strong setae, as long as the width of the femur. Surstyli each with two prensisetae and an apical prong or spur. Within the Sphenella group of genera, the genus Oedosphenella is characterized by the following combination of characters: Hind femur with a row of strong setae anteroventrally, vein R 4+5 bare or with 1–3 setae at the node at most, scutellum slightly convex and dull brown to strongly convex and shiny, never flat and yellow, surstyli each with two prensisetae and with a posterior prong. All four known species are easily identified by their wing pattern (Fig. 1A–D) and the male genitalia that are species-specific (Munro 1957; fig. 3C). Remarks. The genus Oedosphenella was erected as a subgenus of Sphenella Robineau-Desvoidy by Frey (1936) for the sole species Tephritis canariensis Macquart. The main characters separating it from the latter being the strongly convex and shiny scutellum, the shorter proboscis and the stronger wing pattern. Munro (1957) redefined the genus and gave the following characters to separate it from Sphenella: vein R 4+5 bare, at most 1–3 setae on the node, male with the surstyli with two prensisetae each and a posterior prong, stating that neither the strong wing pattern nor the shorter proboscis are of generic value. He also hesitatingly described Bevismyia Munro as a new genus separate from Oedosphenella partly due to the wide geographical disjunction of the two known species, B. basuto Munro and O. canariensis, respectively from Lesotho and the Canary Islands. Other characters pointed out by Munro (1957) to differentiate the genera are the more angular head in Bevismyia and the only slightly convex scutellum, which is not shiny. However, he noted that it was not his intention to postulate that widely separated species could not belong to the same genus and that the difference in the shape of the head may not prove of generic value (Munro 1957). In fact, his argument of the large geographical distance to separate congeners was rendered invalid by the transfer of Oedaspis auriella (Munro 1939) from South Africa to Oedosphenella by Freidberg & Kaplan (1992), thus creating a genus with a largely fragmented distribution. The remaining differences between the two genera are the shape and pilosity of the scutellum (convex and strongly shining in Oedosphenella and at most slightly convex and dull in Bevismyia) and the slightly more angular shape of the head in the latter (Freidberg 1987). These characters seem rather poor for separating genera, and (as suggested by Freidberg & Kaplan 1992) we consider Bevismyia to be a subjective junior synonym (syn. nov.) of Oedosphenella.