Limnophora tigrina (Am Stein), 2010

Michelsen, Verner, 2021, Macaronesian Muscidae (Diptera). II. The genus Limnophora Robineau-Desvoidy with description of a new Canarian endemic species, Zootaxa 4952 (1), pp. 101-127 : 121-124

[ Limnophora tigrina (Am Stein) ]

( Figs 11D‒F )

Limnophora tigrina still appears on the newest check list of Canarian Diptera by Báez & Oromí (2010), although the existing Canarian records of “ notata (Fallén) ” by Macquart (1839) and Santos Abréu (1976) [posthumous unedited publication from the 1930’es] have never been verified. Both records are clearly based on misidentifications, as L. tigrina is easily confused with the Canarian species L. obsignatula , L. paneliusi and L. quaterna . The four species share the characteristic “ Anthomyia -pattern” on the mesonotum. I agree with Hennig (1959) that the present species should be removed from the list of Canarian Muscidae despite its documented occurrence in Morocco and Tunisia.

Material examined. [ NHMD]: Large sample of males and females from: Austria, Czech Republic, Denmark, France (incl. Corsica), Germany, Italy (Sicily), Portugal, Russia, Spain and Sweden. Also from Morocco, Tunisia and Turkey.

Diagnosis. Small to medium sized, wing length 3.9‒5.7mm. Male: Arista short-plumose, longest branches fully half as long as width of postpedicel. Frons at narrowest point 1.0‒1.4 times as wide as ocellar tubercle, black frontal vitta at this point 1.5‒2.0 times wider than adjacent silvery white fronto-orbital plates. Fronto-orbital plate without orbital setulae, robust frontal setae 7‒10, extended to level of anterior ocellus. Frons lying slightly behind moderately produced facial margin. Mesonotum whitish grey pruinose with a contrasting brownish black “ Anthomyia pattern” consisting of a pair of large squarish marks in front of the suture, a broad band immediately behind the suture and a basal scutellar band covering most of the discal surface and connected to the scutal band by a narrow median dark stripe. Presutural acrostichal field with setulae only, arranged in 4 irregular rows confined to middle third. Calypteres whitish, well set off from brownish tinged wing membrane; vein M 1 slightly curved forward in distal part. Mid femur with 2 subapical pd setae and on basal two-fifths with 3‒5 robust pv setae; mid tibia with 2 pd setae inserted above and below middle. Hind femur distally with 2–3 robust av setae, without pv setae. Sternite I bare. Sternite V with hind marginal setae in middle enlarged and forming a dense palisade ( Fig. 11F ); hypopygium as in Figs 11D, E . Female: Frontal triangle with straight margins, confined to upper two-thirds of frontal vitta, often darkly pruinose on distal part. Fronto-orbital plate with 2 reclinate orbital setae and 5‒6 inclinate frontal setae. Dark pattern on mesonotum reduced compared to the male: scutal band behind the suture dissolved into a pair of squarish dorsal marks and a pair of smaller marks above the wing bases; basal scutellar dark band also much reduced. Basal pv setae on mid femur fine; hind femur with 1‒2 distal av setae. Ovipositor similar to those of other examined species with a mesonotal “ Anthomyia -pattern”, but distinguished by combination of a fully developed sternite VI with only 1pair of hind marginal setae and the absence of dorsal hindmarginal setulae on tergite VIII. See Table 1 for more ovipositor characters.

Distribution. A widespread Palearctic species, but not Macaronesian.

Figures

FIGURE 11. Limnophora setinerva Schnabl (A‒C), L. tigrina (Am Stein) (D‒F). Males. Sternite V (A, F); hypopygium, caudal (B, D) and lateral (C, E). Same scale.