Syneches fuscus, 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 : 37-39

Syneches fuscus sp. nov.

( Figs 23A–E , 24A–F , 53 )

Diagnosis. Medium size (3.9 mm) ( Fig. 23A ). Antenna dark brown ( Fig. 23C ). Scutum dark brown, rounded, as broad as mesopleuron in lateral view, covered with reddish brown pruinescence ( Fig. 23B ). Legs yellow except coxae, trochanters, basal third of fore femur, basal half of mid femur, fore tibia (except base yellow), fore tarsi and mid and hind tarsomeres 3–5 brown to dark brown ( Figs 23A, D ); hind femur with several V spiniform bristles inserted on short tubercles on apical third ( Fig. 23D ). Wing sub-hyaline, brown; pterostigma long, oval, dark brown, about 4 x longer than wide, extended 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 ( Fig. 23E ).

Description. Holotype male ( Fig. 23A ). Body length: 3.9 mm; Wing length: 3.6 mm. Head ( Fig. 23C ). Ocellar triangle protuberant, covered with reddish brown pruinescence; 2 pairs of ocellar bristles, anterior pair long, about 2 x longer than posterior pair. Face black covered with reddish brown pruinescence. Antenna dark brown; postpedicel short oval, about 1.5 x longer than wide, slightly longer than preceding segments combined, covered with brown pruinescence, 1 mediodorsal long bristle as long as postpedicel; antennal stylus dark brown, about 3 x longer than preceding segments combined, short pubescent, except apical 1/6 bare. Proboscis yellow, except basal third brown; palpifer and palpus dark brown; palpus short, about 1/3 length of proboscis, covered with concolorous pruinescence, with 2 bristles longer than palpus (1 medioventral, 1 apical), and 3 shorter bristles (2V on basal half, 1V on apical half). Postcranium black, covered with reddish brown pruinescence. Thorax ( Figs 23A, B ). Proepisternum short; prosternum isolated, not fused to proepisternum. Thorax mostly dark brown and covered with reddish brown pruinescence, with posterior margin of pprn lb and anterior margin of pal cal dark yellow. Scutum rounded, as broad as mesopleuron in lateral view. Chaetotaxy: acr 6-serial, dc uniserial, bristles short and sparse; prescutellar disc with 2 acr and 2 dc longer, posterior pair longest and curved apically; 3 long npl, strong and closely each other; 2 pal bristles (anterior short and thin, posterior long and strong, about 3 x longer than anterior one); scutellum with 12 marginal bristles (1 parallel apical, 1 long, strong and parallel subapical, about 2 x longer than apical bristle, 4 lateral bristles, about as long as apical). Legs ( Figs 23A, D ). Fore femur slightly swollen on basal half, mid femur slender, hind femur slightly swollen. Legs with coxae, trochanters, basal third of fore femur, basal half of mid femur, fore tibia (except base yellow), small spot at apex of hind femur, fore tarsi and mid and hind tarsomeres 3–5 brown to dark brown, otherwise yellow. Chaetotaxy: fore tibia with 1D series of bristles slightly longer than covering ones; mid femur with 1AD series of long bristles on basal half, 1AV and 1PV series of long bristles, shortening toward femur apex; mid tibia with 1AD long on basal third, 2PD long, 1AV and 1PV long and strong, all subapical; hind femur with 1AV series of long and sparse spiniform bristles, V short spiniform bristles inserted on short tubercles on apical third; hind tibia with 1AD long bristle on apical half, 1AD long subapical, 1AV and 1PD strong subapical bristles. Wing ( Fig. 23E ). Sub-hyaline, brown; pterostigma oval, dark brown, about 4 x longer than wide, extended from apex of R 1, 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 dark brown. Abdomen. About 2 x longer than thorax; dark brown, covered with reddish brown pruinescence; bristles dark brown, dorsal ones shorter, laterodorsal ones longest. Male terminalia ( Figs 24A–D ) (Paratype from Rio de Janeiro). Hypandrium with shallow concavity on distal margin, forming two short lobes, each one with truncate apex and minute digitiform protuberance on internal margin bearing 1 long apical bristle as long as exposed part of phallus. Phallus short with truncate apex, with one short and slender lateral flaps, arising from middle of phallus and pointing to phallus base. Postgonite long, wide and sclerotized, as long as exposed part of phallus. Dorsal connection of epandrial lamellae narrow. Epandrial lamella wide in lateral view, concave on apical third, with one long and narrow dorsoapical projection.

Female. Similar to male. Female terminalia ( Figs 24E, F ). Tergite 8 rectangular, slightly longer than wide, distal margin slightly concave; sternite 8 about 1.5 x longer than wide, suddenly narrowed on basal half, membranous on central portion of basal half, distal margin slightly concave, with long marginal bristles; tergite 10 U-shaped with narrow apex, as long as tergite 8, bearing long bristles on apical half; sternite 10 oval, as long as cerci, covered with several short bristles; cercus long, covered with bristles shorter than cercus.

Type material examined. HOLOTYPE ♂ ( INPA) labelled: “ BRASIL, MG [Minas Gerais], Poços de Caldas, Fazenda Eucalipto , 14–15.ix.2017, 21°53′33.2″S 46°33′03.8″W, 1.327 m ” “Arm[adilha] Pennsylvania, Fusari, L.M., Desidério, G.R., Pereira, E.B. cols.” “ HOLOTYPE, Syneches fuscus Soares, Freitas-Silva & Ale-Rocha ” [red label] . Holotype condition: good, except left hind leg glued to paper triangle, right wing damaged; not dissected. PARATYPES. Rio de Janeiro: Nova Friburgo (Mury), Macaé de Cima, P. Amantes da Natureza, 22°24′42″S 42°31′13″W, Armadilha de Malaise (sede), 20–23.ix.2015, Amorim e eq. cols. (1 ♀, INPA) ; Est. Do Rio, Itatiaia, Maromba , Barretto col., ix.[1]946 (1 ♂, INPA; 1♂, MZUSP) . São Paulo: Jundiaí, Pq. Florestal Serra do Japi, Cachoeira Paraíso, 23°14′33″S 46°57′03″W, 28.viii.2007, Luz u.v./branca, Lecci , Moretto & Nascimento cols. (1 ♂, MZUSP) ; Eng. Lefevre, C. Jordão : 1200 m, 28.ix.1962, L.T.F. Papavero, Rabello, L. Silva & Zanettin (1 ♂, INPA; 2 ♂, MZUSP) .

Distribution. Brazil (Minas Gerais, Rio de Janeiro and São Paulo) ( Fig. 53 ). Syneches fuscus sp. nov. is known only from the Atlantic Forest biome, with all the specimens collected above 1,000 meters in altitude.

Variation. Some specimens differ from the holotype in having the lateral scutellar bristles varying from 3–4.

Remarks. The new species is similar to S. tenebricus by the predominantly dark brown color and hind femur yellow with brown spot at apex. However, S. fuscus is differs by the dark brown antenna, basal third of fore femur and basal half of mid femur brown, while S. tenebricus has antenna yellow, fore femur brown, mid femur yellow, besides the features of male terminalia.

Etymology. From the Latin fuscus = dark, in reference to the predominantly dark brown color of the species.

Figures

FIGURE 23. Syneches fuscus sp. nov. A–C. Holotype male. A. Habitus, lateral view; B. Thorax, lateral view; C. Head, lateral view. D–E. Paratype (male from Rio de Janeiro). D. Hind leg, anterior view. E. Wing.

FIGURE 24. Syneches fuscus sp. nov. A–D. Male terminalia (paratype from Rio de Janeiro). 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. Apex of phallus and postgonite, ventral view. E–F. Female terminalia (paratype from Rio de Janeiro) in dorsal and ventral views respectively. Scale bars = 0.1 mm.

FIGURE 53. Syneches Walker. Geographical records of S. fasciatus sp. nov.; S. fuscus sp. nov.; S. plaumanni sp. nov. and S. smithi sp. nov. in Brazil.