Lactistomyia tuberculata, Ale-Rocha, Rosaly, 2008

Ale-Rocha, Rosaly, 2008, Revision of the Neotropical genus Lactistomyia Melander (Diptera, Hybotidae, Hybotinae), Zootaxa 1692, pp. 1-25 : 18-20

Lactistomyia tuberculata sp. n.

(Figs. 48–53, 63)

Diagnosis. Wing homogeneously pale brown; hind femur strongly inflated, 13 short ventral spines with very swollen basal tubercles being the last 2 spines inserted on doubled tubercles; posteroventral row irregular, not aligned, with 9 spines on basal three-fourths, longer than ventral ones with basal tubercles strongly developed; hind tibia remarkably curved, anterior surface flattened with longitudinal soft furrow and small sub-basal ventral tubercle.

Holotype male. Body: 5.6 mm. Wing: 5.4 mm.

Description. Antenna brown; pedicel with short bristles; postpedicel about twice longer than wide, slightly longer than scape and pedicel combined; arista 2.5 times length of antenna. Face narrow, black with brown pruinescence. Palpus pale brown to yellow; proboscis dark yellow. Ocellar pair short, parallel, yellow, weak and almost erect. Postcranium brown with gray pruinescence; postocular setae short, weak, yellow and scattered; occipital setae reduced to few ones on mid height of postcranium and some bristles on the margin of buccal opening and foramen.

Thorax with brown pruinescence, more dense and mixed with sparse grayish pruinescence on acrostichal strip; scutum dark brown with posterior margin of postpronotal lobe and postalar callus pale brown to yellow; pleurae brown. Bristles yellow, weak, short anteriorly, elongate laterally and approximately 1.5 times length of anterior bristles on the prescutellar disc; pronotum with short marginal uniserial bristles; 1 npl faintly differentiated; 2 weak pal; scutellar bristles short and weak, 1 preapical pair convergent, slightly differentiated, 5 lateral bristles about two-thirds length of preapical pair and 1 apical pair convergent (Fig. 48).

Legs dark yellow except hind leg with coxa, trochanter and basal fourth-fifths of femur pale brown and apex of femur yellow. Bristles short, yellow; mid tibia with slender longer bristles on posterior surface. Hind femur strongly inflated; hind tibia remarkably curved, anterior surface nude, flattened with longitudinal soft furrow and small sub-basal ventral tubercle, posterior surface round (Fig. 53); hind tarsus about one-half length of tibia, tarsomere 1 longer than the following tarsomeres combined, tarsomeres 2–4 very short. Outstanding bristles: fore tibia with 1 anteroventral and 1 posteroventral short yellow preapical bristles; fore tarsus without outstanding bristles; mid tibia with 4 short anterodorsal bristles, 1 anterior, 1 anteroventral and 1 posterior short spine-like preapical bristles and 1 long ventral apical bristle surpassing the half of tarsomere 1, all bristles yellow; mid tarsomere 1 with 1 dorsal slightly robust preapical bristle and 2 posteroventral short and strong preapical bristles; hind trochanter with 1 short, strong, black ventral spine; hind femur with 13 short, pale brown ventral spines inserted on very swollen basal tubercles being the 7 apical spines more developed and with varied forms, and the last 2 spines inserted on doubled tubercles (Fig. 53); posteroventral row irregular, not aligned, with 9 spines longer than ventral ones on basal three-fourths with basal tubercles strongly developed; hind tarsus without spines.

tinctly longer on lateral margin of Tg1 and Tg2; sternites with short bristles. Terminalia: hypandrium short, not reaching the apex of left epandrial lamella; hypandrial lobe short, about one-half length of base of hypandrium, with round apex and great preapical outer protuberance (Fig. 49); epandrial lamellae with strong preapical bristles shorter than half of length of respective lamellae (Fig. 50); surstyli short, right surstylus wide, left surstylus narrow (Figs. 51, 52).

Female: unknown.

Type material. Holotype male ( MZSP): “ BRASIL, Minas Gerais (Estado de Minas), Arcerburgo, F. Fortaleza, 12-[1]946, Barretto col.”. Condition: good, dissected; left wing mounted in micro slides.

Distribution: Brazil (Minas Gerais).

Etymology. The specific name is derived from the Latin tuber (lump) in reference to the very swollen basal tubercles on the hind femur.