Syneches flaviscutellatus, Soares & Freitas-Silva & Ale-Rocha, 2021

Soares, Matheus M. M., Freitas-Silva, Rafael A. P. & Ale-Rocha, Rosaly, 2021, Review of Brazilian species of Syneches Walker (Diptera, Hybotidae, Hybotinae), with description of ten new species, Zootaxa 5049 (1), pp. 1-84 : 35-37

Syneches flaviscutellatus sp. nov.

( Figs 21A–D , 22A–C , 57 )

Diagnosis. Medium size (3.5 mm) ( Fig. 21A ). Antenna yellow, but scape brown ( Fig. 21B ). Scutum rounded, as broad as mesopleuron in lateral view, orangish yellow and covered with golden pruinescence ( Fig. 21A ). Pleura yellow, except anepimeron and posterior half of laterotergite brown ( Fig. 21A ). Legs with fore tibia pale brown, but base and apex yellow, fore tarsus, mid and hind tarsomeres 5 and apex of hind femur brown, otherwise yellow ( Figs 21A, C ). Wing sub-hyaline, light brown; pterostigma long, oval, brown, about 3.5 x longer than wide, extending from apex of R 1 and not filling apex of cell r 1; second section of M 1 2 x longer than crossvein r-m; cell bm slightly longer than cells br and cua ( Fig. 21D ).

Description. Holotype male ( Fig. 21A ). Body length: 3.5 mm. Wing length: 3.0 mm. Head ( Fig. 21B ). Ocellar triangle protuberant, covered with reddish brown pruinescence; 2 pairs of ocellar bristles, anterior pair about 2 x longer than posterior pair. Face dark brown. Antenna yellow, but scape brown; postpedicel short oval, about 1.5 x longer than wide, as long as preceding segments combined, covered with concolorous pruinescence, 1 long mediodorsal bristle about as long as postpedicel; antennal stylus brown, about 3.5 x longer than preceding segments combined, short pubescent except on apical 1/5. Proboscis, palpus and palpifer yellow; palpus short, about 1/4 length of proboscis, covered with concolorous pruinescence, with 2 bristles as long as palpus (1 medioventral, 1 apical). Postcranium dark brown, covered with golden pruinescence. Thorax ( Fig. 21A ). Proepisternum short; prosternum isolated, not fused to proepisternum. Pronotum brown, covered with golden pruinescence. Scutum rounded, as broad as mesopleuron in lateral view, orangish yellow, except posterior margin of pprn lb and pal cal pale yellow, scutum covered with golden pruinescence. Scutellum orangish yellow, covered with golden pruinescence. Pleura yellow, with anepimeron and posterior half of laterotergite brown. Mediotergite pale brown with brown median stripe. Chaetotaxy: acr 4-serial, dc uniserial, bristles short and sparse; prescutellar disc with 1 long and convergent acr and 1 long dc; 2 long npl bristles close to each other; 2 pal bristles (anterior short and thin, posterior long and strong, about 4 x longer than anterior); scutellum with 10 marginal bristles (1 convergent apical bristle, 1 long and strong subapical bristle, about 2 x longer than apical bristle, 3 lateral bristles similar to apical bristle). Legs ( Figs 21A, C ). Femora slender. Legs with fore tibia pale brown, but base and apex yellow, fore tarsus, mid and hind tarsomere 5 and apex of hind femur brown, otherwise yellow. Chaetotaxy: bristles pale yellow to dark brown; fore tibia with 1D series of bristles slightly longer than covering bristles; mid femur with 1AV and 1PV series of long bristles, shortening towards apex of femur; mid tibia with 1D short bristle on basal third, 1AV and 1PV long and strong subapical bristles; hind tibia with 1PD short near mid-length of tibia and 1D short subapical bristle, 1PD series on apical half, lengthening towards apex of tibia. Wing ( Fig. 21D ). Sub-hyaline, light brown; pterostigma long, oval, brown, about 3.5 x longer than wide, extending from apex of R 1 and not filling apex of cell r 1; R 2+3 slightly angulate near apex; second section of M 1 2 x longer than crossvein r-m; cell bm slightly longer than cells br and cua. Halter pale brown. Abdomen ( Fig. 21A ). About 2 x longer than thorax. Brown, covered with concolorous pruinescence; bristles dark brown, dorsal ones shorter, laterodorsal ones longer. Male terminalia ( Figs 22A–C ) (Paratype, typelocality). Hypandrium slightly convex on distal margin, with two short triangular subapical protuberances, each bearing 1 long bristle as long as exposed part of phallus. Phallus long, narrower and rounded on apex, with 1 long and strong lateral spiniform projection, reaching base of phallus. Postgonite shorter than phallus, sinuous on apical half, rounded apically. Epandrial lamella wide, narrowing suddenly on apical half, with short and narrow apicodorsal projection.

Female. Unknown.

Type material. HOLOTYPE ♂ ( INPA) labelled: “ BRASIL, MT [Mato Grosso], Chapada dos Guimarães, 15°25′46,7″S 55°50′4,18″W, 03–13.ix.2008, Almeida, Kawada, Fernandes & Rosa col.” “ HOLOTYPE, Syneches flaviscutellatus Soares, Freitas-Silva & Ale-Rocha ” [red label] . Holotype condition: good; not dissected. PARATYPE. Same data as holotype (1 ♂, MZUSP) .

Distribution. Brazil (Mato Grosso) ( Fig. 57 ). Syneches flaviscutellatus sp. nov. is registered only from the Cerrado biome.

Variation. The male paratype differs from the holotype in having the mediotergite wholly brown.

Remarks. The new species is similar to S. fasciatus sp. nov. by the brown pronotum clearly contrasting with the extensively orangish yellow scutum, but it differs by the scutum lacking acr dark stripe and the male terminalia with hypandrium slightly convex on distal margin, with two short triangular subapical protuberances (see also “Remarks” under S. fasciatus sp. nov.).

Etymology. From the Latin, flavus = yellow, and scutellum = scutum, in reference to the color of the scutum.

Figures

FIGURE 21. Syneches flaviscutellatus sp. nov. A–C. Holotype male. A. Habitus, lateral view; B. Head, lateral view; C. Hind leg, anterior view. D. Paratype (male from type-locality). Wing.

FIGURE 22. Syneches flaviscutellatus sp. nov. Male terminalia (paratype from type-locality). A. Epandrium and hypandrium, phallus and postgonite darkened, ventral view; B. Epandrium with cerci, dorsal view; C. Left epandrial lamella with cercus, lateral view. Scale bars = 0.1 mm.

FIGURE 57. Syneches Walker. Geographical records of S. annulipes Bezzi, 1909; S. flaviscutellatus sp.nov. and S. longiflagellatus Ale-Rocha & Vieira, 2008 in Brazil.