Syneches tomentosus Smith, 1962

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 : 68-69

Syneches tomentosus Smith

( Figs 45A–E , 46A–E , 55 )

Syneches tomentosus Smith, 1962: 216 ; 1967:10 (cat.); Yang et al., 2007 (cat.). Type locality: Nova Teutônia, Santa Catarina, Brazil.

Diagnosis. Medium size (3.3 mm) ( Fig. 45A ). Antenna brown except postpedicel dark brown and apex of pedicel and base of postpedicel paler ( Fig. 45C ). Scutum rounded, as broad as mesopleuron in lateral view, covered with reddish brown pruinescence ( Fig. 45B ). Legs with fore tibia dark yellow, apex of fore femur with a small spot, fore tarsus and mid and hind tarsomeres 3–5 brown ( Figs 45A, D ); hind femur slender ( Fig. 45D ). Wing sub-hyaline, pale brown; pterostigma about 3.5 x longer than wide, oval, brown, with a marginal proximal invagination, extended from apex of R 1 and not filling apex of cell r 1; second section of M 1 longer than crossvein r-m ( Fig. 45E ).

Re-description. Holotype male. Body length: 3.3 mm. Wing length: 3.4 mm. Head ( Fig. 45C ). Ocellar triangle protuberant, covered with gray pruinescence; 2 pairs of ocellar bristles (anterior pair about 2 x longer than anterior). Face wide, black, covered with gray pruinescence. Antenna brown except postpedicel dark brown and apex of pedicel and base of postpedicel paler; postpedicel short oval, about 1.3 x longer than wide, about as long as preceding segments combined, covered with brown pruinescence, 1 long mediodorsal bristle, about 2 x longer than postpedicel; antennal stylus brown, about 3 x longer than preceding segments combined, covered with short microtrichia, bare on apical third. Proboscis yellow, palpus and palpifer brown; palpus about 1/3 length of proboscis, covered with golden pruinescence, with 2 bristles as long as palpus (1 medioventral, 1 apical). Postcranium black, covered with reddish brown pruinescence. Thorax ( Fig. 45B ). Proepisternum short; prosternum isolated, not fused to proepisternum. Thorax dark brown covered with reddish brown pruinescence, except posterior margin of pprn lb and pal cal pale yellow and anepimeron paler. 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-most dc longest and curved apically; 2 npl, long, strong and close to each other; 2 pal cal bristles (anterior short and thin, posterior long and strong, about 3 x longer than anterior); scutellum with 12 marginal bristles (1 convergent apical pair, 1 long, strong and parallel subapical pair, about 1.5 x longer than apicals, 1 lateral slightly longer than apical and 3 lateral bristles similar to apical). Legs ( Figs 45A, C, D ). Fore femur slightly swollen on basal half, mid and hind femora slender. Legs with fore tibia dark yellow, apex of fore femur with small spot, fore tarsus and mid and hind tarsomeres 3–5 brown. Chaetotaxy: fore tibia with 1D series of bristles slightly longer than cover bristles; mid femur with 1AV and 1PV series of long bristles, shortening towards femur apex; mid tibia with 1D long bristle on basal third, 1AV and 1PV long subapical bristle; hind femur with 1AV series of long, sparse and thin bristles; hind tibia with 1AD long on basal half, 1AD, 1D and 1PD long subapical bristle. Wing ( Fig. 45E ). Sub-hyaline, pale brown; pterostigma oval, brown, with marginal proximal invagination, about 3.5 x longer than wide, extended from apex of R 1, not filling apex of cell r 1; R 2+3 slightly angulate apically; second section of M 1 longer than crossvein rm; cell bm longer than cells br and cua. Halter dark brown, except base of stem dark yellow. Abdomen ( Fig. 45A ). About 2 x longer than thorax. Dark brown, covered with reddish brown pruinescence; bristles brown, dorsal short, laterodorsal long. Male terminalia (specimen compared with holotype, Figs 46A–C ). Distal margin of hypandrium with shallow mid-width concavity, forming two short lobes, each bearing 1 long apical bristle about as long as exposed part of phallus. Phallus short and strong, apex rounded, lateral flaps short and strong, pointing anteriorly to base of phallus, arising next to base of phallus. Postgonite short and wide, about as long as exposed part of phallus, more sclerotized on basal third, narrowing apically. Dorsal connection of epandrial lamellae wide. Epandrial lamella wide in lateral view, concave on apical 1/4 and 1 long and narrow apicodorsal projection.

Female. Similar to male, except by wing hyaline and pterostigma pale brown. Female terminalia ( Figs 46D, E ). Tergite 8 slightly longer than wide, distal margin with long bristles; sternite 8 about 1.5 x longer than wide, narrowing on proximal third, membranous on central part of proximal 3/4, distal margin bearing long bristles; cercus shorter than sternite 10.

Type material examined. HOLOTYPE ♂ ( NHMUK) labelled: “ BRASIL, [Santa Catarina, Seara], Nova Teutônia, 16.ix.1937, Fritz Plaumann ” “(Hol. ♂ n°1938-40)” . Holotype condition: good, right wing mounted between cover slides. PARATYPES: Same data as holotype (1 ♀, NHMUK) ; idem, 21.ix.1938 (1 ♂, NHMUK) ; idem, 31.xii.1938, (1 ♀, NHMUK) .

Additional material examined: BRAZIL. Santa Catarina: Nova Teutônia, Fritz Plaumann , x.1971, 27°11′S 52°23′W, Compared with holotype, Syneches tomentosus, Smith, 1962 , Det. R. Ale-Rocha [green label] (1 ♂, 1 ♀, INPA) ; idem, 300–500 m, x.1971 (8 ♂, 8♀, MZUSP) ; idem, ix.1971 (3 ♀, MZUSP) ; idem, i.1976, Cal. Acad. Sci. Coll. (2 ♂, 1 ♀, CAS) ; idem, ix.1976 (2 ♂, CAS) ; idem, viii.1977 (1 ♂, CAS) ; idem, xi.1977 (62 ♂, 59 ♀, CAS; 10 ♂, 10 ♀, INPA) ; idem, x.1977 (3 ♂, 3 ♀, CAS) . Paraná: Piraquara, Mananciais da Serra Mar , 25°29′46″S 48°58′54″W, 01.xi.2007, Varredura, J.A. Rafael col. (1 ♂, INPA) .

Distribution. Brazil (Paraná * and Santa Catarina) ( Fig. 55 ). Syneches tomentosus is known to occur only in the Atlantic Forest biome.

Variation. Apex of pedicel and base of postpedicel yellow. Scutellum pale brown, with anterior margin yellow and the lateral scutellar bristles vary from 4–6. On the legs, mid tarsomeres 3–4 yellow in some specimens.

Remarks. Syneches tomentosus is similar to S. nordestino sp. nov. by the medium size, thorax dark brown covered with reddish brown pruinescence and legs mostly yellow. However, S. tomentosus can be differentiated by the oval pterostigma, about 3.5 x longer than wide, with a marginal proximal invagination and postpedicel mostly dark brown (pterostigma absent and postpedicel pale yellow in S. nordestino sp. nov.). Additionally, the characters of the male terminalia contribute to distinguish these species. See also “Remarks” under S. nordestino sp. nov.

Figures

FIGURE 45. Syneches tomentosus Smith, 1962 (male from type-locality, compared with holotype). A. Habitus, lateral view; B. Thorax, lateral view; C. Head, lateral view; D. Hind leg, anterior view; E. Wing.

FIGURE 46. Syneches tomentosus Smith, 1962. A–C. Male terminalia (specimen from type-locality, compared with 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 (specimen from type-locality). in dorsal and ventral views respectively. Scale bars = 0.1 mm.

FIGURE 55. Syneches Walker. Geographical records of S. moraballi Smith, 1963; S. tomentosus Smith, 1962 and S. vidali Ale- Rocha & Vieira, 2008 in Brazil.