Glabellula perkovskyi Evenhuis

Evenhuis, Neal L., 2013, New microbombyliids (Diptera: Mythicomyiidae) from Eocene Baltic and Rovno ambers, with notes on previously described amber species, Zootaxa 3731 (3), pp. 371-380 : 375

Glabellula perkovskyi Evenhuis , new species

( Figs. 3, 4 , 7, 10 )

Type. Holotype male from Ukraine: exact locality unknown, DU-140. The holotype is in a fairly clear, polished, amber-colored trapezoidal-shaped piece ( Fig. 13 ) measuring 11 x 11 x 18 x 4 mm in circumference by 2–4 mm thick. Rovno amber; Late Eocene. In addition to much plant debris, there are 2 syninclusions with the holotype in this piece of amber: 1) another Glabellula specimen unfortunately cut sagittally when the piece was originally prepared and in too deteriorated condition to make a determination; and 2) an undetermined rhagionid. Holotype in SIZK.

Diagnosis. Most similar to Glabellula grimaldii Evenhuis and G. electrica (Hennig) based on the shared wing character of a stump vein extending from crossvein bm-cu+ dm-cu, but it can be separated from both by the conspicuous yellowish pattern dorsally and posterolaterally on the abdominal tergites (abdominal tergites all black dorsally and laterally in G. grimaldii and G. electrica ).

Description. Male (Figs. 3,4). Length: 1.3 mm. Head. Black; eyes dichoptic, separated at vertex by 1.5 x distance between lateral ocelli; antennae dark brown; scape minute; pedicel cylindrical, slightly wider than long; first flagellomere ( Fig. 7 ) ovoid, length about 1.5 x greatest width; second flagellomere cylindrical, rounded apically, about 1/3 length of first flagellomere; apical sensillum not visible; proboscis brown, short, barely exserted; palpus not evident.

Thorax. Mesonotum and scutellum black, pleura dark brown; legs dark brown; halter stem and knob brown.

Wing ( Fig. 10 ). Hyaline; costal and radial veins yellowish brown, other veins yellowish; costa ends beyond end of R4+5 1/3 way to M1; vein Sc incomplete, ending about at level of origin of Rs; vein R2+3 originates at basal 1/3 of Rs; vein R4+5 straight to wing margin, ending in costa beyond level of end of vein M2; vein M1 straight toward wing margin; vein M2 fairly straight to wing margin; stump vein present on crossvein bm-cu+dm-cu; vein A1 straight to wing margin.

Abdomen. Dorsum brown, with thin yellowish posterior vittae on segments II–VII extending from dorsum to posterolateral portion of each segment. Genitalic structures hidden, not discernable

Etymology. The specific epithet honors Evegeny Perkovsky for his efforts at bringing these specimens to my attention so they could be named and described.

Figures

FIGURES 1 – 4. Rovno amber Glabellula. Figs. 1 – 2. Glabellula aggregata, n. sp.: 1, amber piece showing positions of holotype male and paratypes. 2, Detail of holotype male. Figs. 3 – 4. Glabellula perkovskyi, n. sp.: 3, amber piece showing position of holotype at upper right; undetermined rhagionid in center of piece. 4, Detail of holotype male.

FIGURES 5 – 12. Antennae and wings of amber fossil Mythicomyiidae. Figs. 5 – 9. Antennae: 5, Glabellula brunnifrons Evenhuis; 6, Glabellula electrica (Hennig); 7, Glabellula perkovskyi, n. sp.; 8, Glabellula kuehnei Schlüter. 9, Riga toni, n. sp. Figs. 10 – 12. Wings: 10, Glabellula perkovskyi, n. sp.; 11, Carmenelectra pernigra, n. sp.; 12, Riga toni, n. sp.

FIGURES 13 – 14. Reconstructions of amber mythicomyiids. 13, Glabellula aggregata, n. sp., drawn from specimen at slightly different angle than shown in Fig. 2; 14, Carmenelectra shehuggme, n. sp., drawn from specimen at slightly different angle than shown in Fig. 17.