Ganaspis Foerster , 1869
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|Ganaspis Foerster , 1869|
Taxon classification Animalia Hymenoptera Figitidae
Common in Africa as elsewhere, yet only recorded in the key to genera in Quinlan (1986). The genus is very difficult to circumscribe, not always certainly distinguished from Aganaspis , Didyctium and Hexacola . At the same time, many smaller genera of the Ganaspini may actually be ingroups in the genus as currently conceived. Thus, a thorough analysis of the boundaries of this genus will most likely highlight the need to either synonymise a number of apomorphic small genera back into Ganaspis , or to recognise species groups of Ganaspis as separate genera. However, the difficulty to circumscribe the latter and to delineate them from the other major genera of Ganaspini suggests that this cannot be done without a thorough phylogenetic analysis. Of the several genera that Lin (1988) described in his revision of Taiwanese eucoilines, we have recognised Gastraspis (easily recognisable at least in females), but we have not been able to establish whether the plentiful African Ganaspis with very wide scutellar plates could be assigned to his Epochresta , and thus we have not treated the latter as an African genus.
Ganaspis is a vast and rather morphologically heterogenous genus, and can be regarded as currently comprising all of the typical Ganaspini that are not “different” enough to warrant a genus of their own. Typical Ganaspis are small, somewhat pale, compactly built eucoilines. Other characteristics include: a deep, more or less globular, head; a rather elongate mesosoma; more or less long hairlines on meso- and metacoxae; scutellum with a foveolate dorsal surface; a large, flat or convex scutellar plate; smooth lateral bars; a posterior metapleural margin with a circular or elongate excision; a narrow but distinct petiolar rim; broad wings with a rather truncate or faintly excised apex; and a deep fore wing marginal cell with curved sides - but most or all of these characters may vary within the genus. The typical Ganaspis are very often superficially similar to Leptopilina (also common parasitoids of Drosophilidae ), but usually rather easily separated from them by having a modifed F1 in male antennae, and a distinct hair tuft on the metapleural corner. In order to facilitate recognition and sorting of Ganaspis in the Afrotropical region, we recognise the following morphological types of Ganaspis as characteristic within the Afrotropical fauna.
The apparently most common appearance of Ganaspis is one rather close to the European type, with long coxal hairlines, a circular or elongate excision of posterior pronotal margin, a wide scutellar plate not reaching the posterior end of scutellum, rather pale colour (middle brown body and yellow or pale brown legs). In some species, including most of the African taxa there are distinct patches of dense white pubescence on the pronotum and axillulae; marginal cells of wings are relatively homogenous with stong dominance for a short deep closed type with curved sides; some forms have a striking tooth on the metapleural edge, distinctly bi- or tricolored antennae, or large scutellar foveae.
A similar morphological type can also be seen in forms with an even larger scutellar plate, that is distinctly convex, but with a posterior depression and often an elongate-oval glandular release pit. These species are often relatively large in size. They may coincide with Lin’s (1988) genus Epochresta (but types in TARI have not been available for loan).
Occasional specimens, usually of small size, lack the coxal hairlines and have only short hair tufts.
Many undescribed species, especially from Madagascar, are rather large and remarkably slender-elongate in build and pale in color, somewhat approaching the habitus of Chrestosema and related genera. Occasionally these may have very unusual features such as an elongated petiolar rim. Some of these are similar in appearance to the characteristic Neotropical Ganaspis " neotropica -group".
Other morphological types conform to the most common type in most respects, but differ, for example, in scutellar morphology. Some tiny specimens resemble Endecameris or Didyctium , others Hexacola , many Aganaspis .
Worldwide. Afrotropical records: Seychelles, Tanzania (Kieffer 1911, 1913), Rwanda ( Benoit 1956a), Burkina Faso, Cameroon, Cape Verde, Central African Republic, Democratic Republic of Congo, Gabon, Gambia, Ivory Coast, Kenya, Madagascar, Mauritius, Nigeria, Sierra Leone, South Africa, Uganda, Zambia, Zimbabwe, Yemen (here).
Usually attacking Drosophilidae in various habitats, but sometimes also fruit-infesting Tephritidae or other flies ( Nordlander and Grijpma 1991, Melk and Govind 1999, Vass and Nappi 2000). None of the host records are from Africa.
Ganaspis mahensis Kieffer, 1911c (Seychelles)
Several species remain to be described in Africa.
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