Syneches amorimi, 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 : 11-14

Syneches amorimi sp. nov.

( Figs 4A–E , 5A–E , 51 )

Diagnosis. Medium size (4.5 mm) ( Fig. 4A ). Antenna yellow, but postpedicel brown with yellow base, bearing 2 mediodorsal bristles ( Fig. 4C ). Scutum dark brown, as broad as mesopleuron in lateral view ( Fig. 4B ); pleura yellow except anepisternum brown ( Fig. 4B ). Legs long and slender; fore tarsomeres 1–2 and basal half of hind tibia dark yellow, mid tarsomeres 4–5, fore and hind tarsomeres 3–5 brown, apex of hind femur and apical half of hind tibia dark brown, otherwise yellow ( Figs 4A, D ). Wing sub-hyaline, pale brown; pterostigma wide, brown, about 2.5 x longer than wide, filling apex of cell r 1 ( Fig. 4E ).

Description. Holotype male ( Fig. 4A ). Body length: 4.5 mm; wing length: 3.8 mm. Head ( Fig. 4C ). Ocellar triangle protuberant, covered with gray pruinescence; 2 pairs of ocellar bristles, anterior pair long, about 2 x longer than posterior pair. Face black covered with gray pruinescence. Antenna yellow, but postpedicel brown with yellow base; postpedicel short, oval, about 1.4 x longer than wide, as long as preceding segments combined, covered with golden pruinescence, bearing 2 mediodorsal bristles, one of them almost 2 x longer than postpedicel, other about as long as postpedicel; antennal stylus brown, about 3 x longer than preceding segments combined, short pubescent, bare on apical 1/4. Proboscis and palpus yellow; palpifer brown; palpus short, about 1/4 proboscis length, covered with golden pruinescence, with 2 bristles longer than palpus (1 medioventral and 1 apical). Postcranium black, covered with gray pruinescence. Thorax ( Fig. 4B ). Proepisternum short; prosternum isolated, not fused to proepisternum. Pronotum and scutum dark brown, but posterior margin of pprn lb and pal cal yellow, both pronotum and scutum covered with golden pruinescence, except on prescutellar disc with gray pruinescence; scutum as broad as mesopleuron in lateral view. Scutellum brown, pale on anterior margin, covered with golden pruinescence. Pleura yellow except anepisternum brown and anepimeron and laterotergite with small central brown spot. Mediotergite brown. Chaetotaxy: acr 6-serial, dc uniserial, bristles short and sparse; prescutellar disc with acr and dc bristles biserial long, posterior one of each longest and curved apically; 2 npl long, strong and 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 [paratype ♀] (1 apical pair parallel, 1 subapical pair long, strong and divergent, about 2 x longer than apical pair, 3 lateral pairs similar to apical pair). Legs ( Figs 4A, D ). Long and slender. Fore tarsomeres 1–2 and basal half of hind tibia dark yellow; mid tarsomeres 4–5 and fore and hind tarsomeres 3–5 brown; apex of hind femur and apical half of hind tibia dark brown; otherwise yellow. Chaetotaxy: fore tibia with 1D series of long and sparse bristles; mid femur with 1AV and 1PV series of long bristles, shortening toward apex of femur; mid tibia with 1D long bristle on basal third, 1AV and 1PV long and strong subapical bristles; hind femur with 1AV series of long and thin bristles; hind tibia with 1D long bristle on mid-length, 1AD and 2PD long subapical bristles. Wing ( Fig. 4E ). Sub-hyaline, pale brown; pterostigma wide, brown, about 2.5 x longer than wide, extended from apex of vein R 1 and filling apex of cell r 1; R 2+3 slightly angulate at apex; second section of vein M 1 as long as r-m; cell bm longer than cells br and cua; cells br and cua subequally long. Halter dark brown, except base of stem yellow. Abdomen ( Fig. 4A ). Long, about 2.5 x longer than thorax. Brown, covered with reddish brown pruinescence; dorsal bristles short and dark brown, dorsolateral bristles long and yellow. Holotype male terminalia ( Figs 5A–C ): hypandrium slightly narrowed towards distal margin, with median shallow marginal concavity and two short apical lobes, each bearing 1 long bristle, reaching half-length of exposed part of phallus. Phallus short and wide, apex rounded, lateral flaps short, pointing to base of phallus, arising next to base of phallus. Postgonite slightly longer than exposed part of phallus, slightly sclerotized on basal half. Dorsal connection of epandrial lamellae narrow. Epandrial lamella wide in lateral view, narrower on apical third, with short and narrow apicodorsal projection.

Female. Similar to male, except for yellow scutellum. Female terminalia ( Figs 5D, E ). Tergite 8 rectangular, about 2 x longer than wide, lateral bristles long; sternite 8 long, about 3 x longer than wide, narrower, and membranous on central portion of proximal half; cercus longer than sternite 10.

Type material. HOLOTYPE ♂ ( MZUSP) labelled: “ BRASIL, MG [Minas Gerais], Botelhos, Córrego da Onça , 21°40′90″S 46°22′05″W, Varredura, 02–05.xi.2006, Amorim, Falaschi & Oliveira col., BIOTA-FAPESP” “ HOLOTYPE, Syneches amorimi Soares, Freitas-Silva & Ale-Rocha [red label]” . Holotype condition: left hind femur broken, right hind tarsus broken off, left wing mounted between cover slides, male terminalia dissected and stored in microvial. PARATYPES. Same data as holotype (1 ♀, MZUSP; 1 ♀, INPA) .

Distribution. Brazil (Minas Gerais) ( Fig. 51 ). Syneches amorimi sp. nov. is currently known only from the type-locality, in the Atlantic Forest biome.

Remarks. The new species resembles S. exilis and S. plaumanni sp. nov. due to the slender aspect and long and slender legs. However, S. amorimi sp. nov. differs from the other two species by the yellow scape and pedicel, postpedicel bearing 2 long mediodorsal bristles and pterostigma wide, filling the apex of cell r 1. Contrastingly, S. exilis and S. plaumanni sp. nov. have brown antennae and the pterostigma is long and oval, not filling the apex of cell r 1.

Etymology. This species is named after Dr. Dalton Amorim, Brazilian dipterologist who has contributed substantially to the knowledge of Neotropical Diptera and collected the type material.

Figures

FIGURE 4. Syneches amorimi sp. nov. Holotype male. A. Habitus, lateral view; B. Thorax, lateral view; C. Head, laterodorsal view; D. Hind leg, anterior view; E. Wing.

FIGURE 5. Syneches amorimi sp. nov. A–C. Male terminalia (holotype). A. Epandrium and hypandrium, phallus and postgonite darkened, ventral view; B. Epandrium with cerci, dorsal view; C. Left epandrial lamella with cercus, lateral view. D–E. Female terminalia (paratype from type-locality) in dorsal and ventral views respectively. Abbreviations: cerc—cercus; epand— epandrium; hypd—hypandrium; ph—phallus; hyprct—hypoproct; st—sternite; tg—tergite. Scale bars = 0.1 mm.

FIGURE 51. Syneches Walker. Geographical records of S. amorimi sp. nov.; S. barrettoi sp. nov.; S. catarinae Smith, 1962 and S. digitatus sp. nov. in Brazil.