Insulestremia amorimi sp. n.

(Fig. 1)

Diagnosis. Male Terminalia (Fig. 1A). Gonostyli lobes with less than half length of gonocoxites; main lobe subtriangular, rounded apically and bearing a single megaseta, slightly bent inwards; side lobe longer than the main lobe, with small, spine-like tooth surrounded by short spines at apex. Tegmen 2.5 times longer than width of base, rounded at apex. Ejaculatory apodeme long, thin, sclerotized on basal half.

Description. Male. Body length: 1.24–1.49 mm. Wing length: 1.28–1.53 mm; wing width: 0.49–0.67 mm. Pattern of tergal plaques: 0/1/1/1/1/1/1/0. Flagellomere 4 with three long and flattened sensilla at the apical third, distributed as two at ventral surface and one at dorsal surface; sensilla with length four times longer than base width; flagellomere 3 (Fig. 1B) with one flattened and two pointed sensillum arising from a very large pore. Terminalia. Gonocoxites with dorsomedial lobe variable in size and sclerotization; dorsal transverse bridge at the level of parameral apodemes. Tergite 9 as a wide, short plate. Cerci tapered toward apex, reaching three-quarters length of tegmen.

Female. Body length: 1.95 mm. Wing length: 1.62 mm; wing width: 0.62 mm. Head: Antennae incomplete; flagellomere (Fig. 1C) with very short stem and barrel-shaped node; node with 2 flattened, two- to four-pointed sensilla arising from very large basal pores; setae around base of node oversized as in comparison with male.

Immature stages. Unknown.

Type material. Holotype male: BRAZIL: São Paulo, Ribeirão Preto municipality, Universidade de São Paulo

(USP), Malaise in the woods around Museu do Café Francisco Schmidt, 21 o 10’ 05,53”S 47 o 51’ 23,55” W, 16– 31.i.2015, Amorim D.S. & team of collectors, (MZUSP). Paratypes : BRAZIL: Mato Grosso do Sul, Bodoquena municipality, farm Califórnia, Malaise 04, riparian forest 20 o 41’ 49.9” S 56 o 52’ 54” W, 1 male and 1 female , 06–21.x.2012, Lamas, Nihei & team of collectors (SISBIOTA-Diptera); São Paulo, Ribeirão Preto municipality, Universidade de São Paulo (USP) campus, around Guest House, 593 m, Malaise 2, 21 o 09’ 54’’ S 47 o 50’ 56’’ W, 1 male , 17–28.xii.2019,, Amorim & Riccardi col.; Sertãozinho municipality, Malaise fragment 2, border, 11.viii– 25.viii.2010, 1 male, Vera C. Silva col.; Teodoro Sampaio municipality, P. E. (State Park) Morro do Diabo, Malaise point 1 , 17.ii.2011, 1 male (only the Terminalia), N. W. Perioto & team of collectors; São Carlos municipality, Universidade de São Carlos (UFSCar) campus, DEBE window, caught in flight, iii.2005, 1 male, Urso-Guimarães & Colavite cols. (MZUSP) .

Etymology. The species epithet is to honors the dipterist Dr. Dalton de Souza Amorim, who has been one of the greatest contributors to the knowledge of the Neotropical Diptera and opened the laboratory under his supervision to several visits of AMCN.