Robber Fly Trichardis cribrata (Loew, 1858)*
Family: Asilidae Subfamily: Laphriinae
* ID by Dr. Torsten Dikow
Genus Trichardis
Trichardis (Hermann, 1906) is primarily an Afrotropical genus. It is also recorded for the Palaearctic Region where four species, including one also found in the Afrotropics, were catalogued by Lehr (1988).
There are 25 Afrotropical species. Of the 25 Afrotropical species, eight (32%) are found only in Southern Africa (
apicalis, cribrata, effrena, picta, spicata, terminalis, testacea, turneri). Nine (36 %) are known only from Eastern Africa, three of these being confined to the small Yemenese islands of Socotra and Abd el Kuri. Three (12 %) species are known only from Western Africa. Two species (8 %) are widespread between East and West Africa, one (4 %) is distributed between East and Central Africa, and another is found in both East and Southern Africa.
(While this genus had not been previously recorded from any other region, this author found an undescribed species from India (Oriental Region) and described it in this paper- see link below).
Habitat
Trichardis appears to be a genus largely restricted to grassland and savannah biomes. It is absent from tropical and subtropical areas where forests dominate, and from the winter-rainfall area of the south-western parts of South Africa, which is dominated by succulents and fynbos.
Biology
Nothing is known about the immature stages of any
Trichardis species and biological data relating to the adults are fragmentary. It appears that all species are normally encountered resting on the ground (on sand or peddles) in savannah or woodland biomes (Londt 1994). Only six prey records are known to me. Except for a single dipteran (Tachinidae), all prey items are hymenopterans (4 Halictidae, 1 Masaridae, 1 Pompilidae). The possible predilection for Hymenoptera, and Halictidae in particular, is interesting, but probably not significant as these insects are also commonly found resting on the ground and therefore easily accessible as prey.
(Note: while the above prey records do not include any spiders, this photo shows
Trichardis cribrata with a jumping spider as prey)
Kruger Nat’l Park by ExF
Trichardis cribrata (Loew, 1858)
Kruger Nat’l Park by ExF
Description
Head: Dark red-brown to black, finely silver pruinose except for central parts of face. Antenna orange- brown, black setose except for a few small pale yellow setae; postpedicel not markedly clavate (L:D=3.2:1). Mystax uniformly pale yellowish. Ocellar tubercle with 2 macrosetae. Proboscis and palpi dark red-brown.
Thorax: Dark red-brown to black, silver pruinose except for some bare areas. Postpronotum medially strongly silver pruinose, laterally apruinose, mesonotum apruinose except for silver lateral and posterior margins, macrosetae yellow-white, fine setulae yellowish. Scutellum apruinose except for narrow anterior margin. Anepisternum with pale yellow posterior macroseta, extensively silver pruinose except for apruinose area anteroventrally. Proepimeron anteriorly pruinose, posteriorly apruinose; katepisternum posteriorly pruinose, anteriorly apruinose; anepisternum entirely pruinose.
Legs: Dark red-brown, tibiae orange-brown proximally, pulvilli and empodium of similar length. Hind femur dark red-brown, length:height ratio 3.4:1, ventral tubercles well-developed. Hind tibia lacking ventrodistal spur.
Wing: 4.0×1.6 mm. Costal vein moderately developed around most of wing margin, weakening along anal cell and absent from alula. Membrane extensively microtrichose—discal and r5 cells entirely microtrichose.
Abdomen: Dark red-brown with narrow brown-orange posterior margins, fine pale white setose. T2 dark red-brown, pruinose except for narrow weakly silver pruinose posterior margins laterally.
Type Locality
Loew's material came from ‘Caffraria’, a term used to cover much of the eastern part of present day Southern Africa. In Dr. Londt’s study, this was the only species of
Trichardis found in Kruger NP.
Distribution
The species is a southern African endemic, distributed widely within the eastern half of the subregion (eastwards of about 23°E), but does not appear to occur along the subtropical and tropical eastern coast.
Biology
Adults fly during the summer months of October and March (there is a record for July that needs verification).
(Note: my photos were taken in Sept.)
Habitat
While little information is available concerning habitat, labels suggest that the species is found mainly in Acacia savannah and woodland.
https://bioone.org/journals/african-inv ... .0210.full
.
© ExFmem
© ExFmem
© ExFmem
© ExFmem
© ExFmem