Paramimegralla vadoni Verbeke

Marshall, Stephen A., 2017, Micropezidae (Insecta, Diptera, Acalyptratae) of Madagascar and a revision of the genus Paramimegralla Hennig, Zootaxa 4290 (2), pp. 244-280 : 272-273

Paramimegralla vadoni Verbeke

Figs 83 ̄87

Paramimegralla Uadoni Verbeke 1956: 479

Paramimegralla vadoni, Steyskal, 1980: 582 ; Barraclough 1992, 9.

Redescription. Length 11̄ 16 mm. Ground colour yellowish brown, subshining, with a circular black mark on the anterior part of the katepisternum, a diagonal silver band on the pleuron and a narrow black central strip on the notum.

Head with frons broad, faintly ridged longitudinally, mostly shining but frontal vitta and lower frons dull microsetulose; ocellar triangle and upper part of orbital strip black, frons otherwise brown; frontal vitta broad but weakly differentiated anterior to ocelli, triangular–tapered posteriorly. Head chaetotaxy complete, with 2 large frontal setae equal in size to orbital seta. Palpus parallel-sided, reddish brown, with scattered black setulae, ventral and distal margin golden microsetulose. Clypeus sparsely but evenly microsetulose, shorter than face plus lunule. Length of first flagellomere 1.5X width.

Thorax uniformly subshining brown except for a black dot on the anterior katepisternum, a central longitudinal line on the anterior part of the notum (often absent or reduced) and a diagonal silver strip running from suture down across the posterior margin of the anepisternum and down the katepisternum just in front of the katepisternal seta row. Proepisternum with short, inconspicuous ventral setae. Legs pale brown except the pale yellow tarsomeres one and two and the darker brown tarsomeres 3̄5 of the fore leg and the white tarsomeres one and two (or 1̄3) of the hind leg. Hind femur not flattened, hind tibia not sulcate.

Wing with broad basal, discal, and preapical bands and a narrowly infuscated apex. Anal cell entirely bare; CuA2 straight, in line with or distal to dm̄cu, distal angle 50 °.

Abdomen pale brown basally, darker distally, Pleural membrane of male pale yellow on segments 1̄3, slightly darker and reddish on 4̄5 and bulging on P3, pleural membrane of female entirely pale yellow. Oviscape broad and uniformly pale brown. Spermathecae on two dissimilar ducts, thinner and shorter duct leading to very small spermatheca, thicker duct distally expanded and branching into two short cylindrical spermathecae on broad and densely convoluted stems. Male with genital fork (S5) with long distally tapered and incurved arms with inner margins densely packed with short, stout setae. Distiphallus broad, short, ending in a dense phallic bulb. Blade of ejaculatory apodeme small, much smaller than epandrium and slightly larger than sperm pump.

Type material. Holotype (sex unknown, MNHN, not examined): Madagascar. Ambanidrambona, J. Vadon. Verbeke (1956) did not indicate the sex of the unique type specimen, but Barraclough (1992) noted that the apex of the abdomen is missing from the type, and that it is presumably a female.

Material examined. Pinned specimens: Madagascar. Ranomafana National Park, Sahamalaotra, 21°14.44’ 47°23.67’, 16.x. 2014, 650m, S.A. Marshall (4♂ sequence MYCRO 037 ̄15, 1♀, DEBU) . Moramanga district , Tamatave, Torotorofotsy, 22km N Andasibe. 18°46.25' 48°25.93', 23̄25.2014, S.A. Marshall (1♂, DEBU). Specimens in alcohol: Barraclough (1992) also records the species from Fampanambo, Perinet, and Ranomafana.

Comments. Paramimegralla vadoni is the only known pale brown to orange micropezid in Madagascar and is further distinguished by the contrastingly dark spot on the anterior katepisternum. Barraclough (1992) notes that some specimens are relatively darkly marked, but are nonetheless paler than congeners and always have the distinctive black katepisternal spot. All of the newly collected and photographed specimens are similarly pale brown to orange. One specimen was barcoded and came out next to P. steineri (note that P. volcanica , a more probable sister taxon to P steineri , was not sequenced).

Figures

FIGURES 83 – 87. Paramimegralla vadOni Verbeke. 83. Male feeding on dung bait, Ranomafana; 84. Male terminalia, left lateral; 85. Abdomen segments 4 ‾ 7, lateral; 86. Male, left lateral, to show everted pleural sac; 87. Spermathecae and associated structures (bursa copulatrix detached and in lateral view).