References
L. abdominalis Wiedemann
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Longina Wiedemann
Diagnosis
Frontal vitta dark brown, project anteriorly between antennal bases. Fronto-orbital plate brown pruinose and narrower anteriorly. Vibrissa present and strong, except in females of L. anguliceps. Scape length at least twice width. Postgena narrowing posteriorly. Occiput inflated, with several strong black setulae in posterior margin of head. Arista densely white pubescent always in proximal half, often more. Presutural scutum with one pair of apical setae on anterior margin. Anterior notopleural seta present and hair-like. One dorsocentral seta. Fore femur with anteroventral and posteroventral rows of small spine-like setae, all same size. Wing partially covered by microtrichia; basally has large bare areas (extending beyond level of r-m in cells r1, r2+3 and r4+5); vein dm-cu not oblique. Scutellum with widely rounded margins.
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Species accounts
1. Longina abdominalis Wiedemann, 1830
2. Longina anguliceps Buck & Marchall, 2004
3. Longina semialba Buck & Marchall, 2004
Wiedemann, 1830
L. abdominalis
Head. First flagellomere tapering toward apex. One fronto-orbital seta. Thorax. Scutum with three longitudinal pruinose stripes. Hind coxa with two lateral setae. Femora without rings on distal third.
NOTE. Males of L. abdominalis bear the most conspicuously elongated scape in the family.
Buck & Marshall, 2004
L. anguliceps
Head. First flagellomere truncate with dorsal and ventral margins parallel. Arista dorsoapical; distal half of arista brown and bare and proximal half white micropubescent. Antennal base shiny laterally and opaque dorsally. Ocellar triangle distinctly protruberant. Two fronto-orbital setae present. Vibrisa small or tiny. Genal seta on a distinct angulate projection. Postgena with dense patch of yellow setulae. Thorax. Pleuron heavily yellowish-grey pruinose. Two well-developed notopleural setae. Hind coxa with two lateral setae. Femora with yellow ring on distal third.
Buck & Marshall, 2004
L. semialba
Head. Antennal bases dark brown to black. Scape and pedicel blackish brown, first flagellomere dark brown. First flagellomere with dorsal and ventral margins slightly cconvergent toward apex. Arista dorso-apicalDistal half of arista black and bare and proximal half white pubescent. Three well-developed fronto-orbital setae. Ocellar tubercle on each side delimited by a furrow that continuesto hind margin of head. Face yellowish to brown, opaque. Gena rounded ventrally, genal seta at most on a very obtuse angle. Vibrisa well-developed, equal to slightly longer than genal seta. Postgena without posterior setulae. Thorax. Anterior notopleural seta very small. Postpronotal lobe with a small seta. Pleuronlargely subshiny. Katepisternum almost bare, except for 1-2 inconspicuous pale setulae dorsally. Hind coxa with one lateral seta. Femora without yellow rong on distal third.
Photo: Cornelio Bota-Sierra
Reference
Buck, M. & Marshall, S. A. 2004. A review of the genus Longina Wiedemann, with descriptions of two new species (Diptera, Neriidae). Studia Dipterologica 11: 23–32.
