Trigonometopus assisensis Lima & Silva 2015, sp. nov.
Creators: name: Lima, Ângela Maria Alves de
name: Silva, Vera Cristina
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Lauxaniidae
Trigonometopus
Trigonometopus assisensis

description: Trigonometopus assisensis sp. nov.   
 (Figs. 1 A-I)   
 Diagnosis: Grey integument. Ocellar setae long, longer than posterior fronto-orbital seta; proclinate setulae covering anterior third of frons to base of anterior fronto-orbital seta; scape shorter than pedicel; first flagellomere long, oval, with recurved apex. Scutum, abdomen and femora covered by setigerous spots; dorsocentral setae arranged 0+2; proepisternal and anepisternal setae absent. Anterior two third of the wing totally covered by brown bands. Female terminalia telescopic, hypoproct and epiproct present, well developed; sternite 8 narrow; 4 spermathecae. Male terminalia: sternite 6 reduced; sternites 7 and 8 almost fused; hypandrium reduced to a stripe; phallus pear-shaped.   
 Description: Male: Head (Figs. 1A, 1B, 1C): Rounded vertex, grey; posterior edge of vertex slightly concave from dorsal view; ocellar triangle placed slightly anterior of vertex, slightly raised. Frons rectangular, short, longer than wide; flat in profile, a shallow dark grey groove running longitudinally from base of ocellar triangle through middle of frons to anterior margin; proclinate setulae from anterior margin to almost half way to vertex, including base of anterior fronto-orbital seta; anterior margin, in dorsal view, concave; lunule exposed. Face grey, almost flat; lower facial margin narrow. Parafacial grey, narrow. Gena grey with setigerous spots. Eye oval, longer than high, brownish red. Antenna brown, inserted in a facial depression: scape shorter than pedicel; first flagellomere long, oval, with recurved apex, pruinose; arista pubescent. Chaetotaxy: outer vertical seta divergent, ⅔ length of inner vertical seta, convergent; ocellar seta ⅔ lenght of postocellar setae, proclinate, divergent; postocellar setae strong, cruciate; anterior fronto-orbital seta and posterior fronto-orbital seta both reclinate, anterior seta ⅔ length of posterior seta; 2 genal setae. Thorax: Scutum flat; grey, with setigerous spots; pleural region grey; scutellum triangular, grey. Chaetotaxy: dorsocentral setae 0+2 (anterior seta away from suture); 1 postpronotal seta; 2 notopleural setae; 1 prescutellar acrostichal seta; 4 rows of acrostichal hairs; intra-alar seta absent; 1 pre- and 1 postsutural supra-alar setae; 2 postalar setae; 1 katepisternal seta; many katepisternal hairs; anepisternal seta absent; proepisternal seta absent; 2 pairs scutellar setae, apical pair parallel. Legs: Coxae and femora brown with grey pruinosity; apex of femora dark yellow; tibiae and tarsi brownish yellow; apical segments of tarsi dark brown. Chaetotaxy: fore coxa with preapical seta; fore femur with posterodorsal and posteroventral rows of setae; mid coxa with 2 basal setae; mid femur with 2 strong apical setae; mid tibia with 1 strong apical anterior seta; hind coxa with 1 apical seta; hind femur with anterior and anteroventral rows of setae; hind tibia with strong 1 posteroventral and 1 anteroventral setae. Wing (Fig. 1D): Hyaline; anterior two thirds with brown bands, spotted at crossveins; costa sapromyziform; R bare; crossvein r-m located before midpoint of discal medial cell; crossvein dm-cu before midpoint of cell r 4+5; longitudinal veins parallel; vein A 1 short. Halter whitish yellow. Abdomen: Grey, with setigerous spots; dorsally with black spots; in males, sternite 6 reduced to a small plate, tergites 7 and 8 almost fused. Terminalia (Figs. 1H, 1I): Epandrium almost rectangular. Surstylus not well developed, fused to epandrium. Hypandrium as an almost complete ring around phallus base, narrow; with median projection, forked. Phallus pear-shaped; phallapodeme U-shaped laterally and forked in ventral view, strongly sclerotized; ejaculatory apodeme small and bell-shaped, in ventral view. Female: As male, except for abdominal apical segments, telescopic, membranous areas widely folded; sternite 8 narrow (Figs. 1E, 1F). Terminalia: With hypoproct and epiproct present. Cercus long. Spermathecae with configuration 2+2; pair of spermathecae united with no differenciation of a commom duct; very short duct linking paired spermathecae (Fig. 1G).   
 Etymology: The specific epithet assisensis was used as a homage to the type-locality, the city of Assis, where a large number of the type specimens were collected. To be treated as a noun in apposition.   
 Type material: Holotype: male; Brazil: São Paulo. Assis, 06.iv.2001, A.M.A. Lima col. (DZUP). Paratypes: Brazil: São Paulo. Assis, Horto Florestal, 05.ix.1992, S.M.D. Mello col., 1 male (MZUSP); Assis, 10.v.1995, V. C. Silva col., 2 males, 1 female (MZUSP); Assis, 27.iv.1999, A.M.A. Lima col., 3 males, 2 females (MZUSP); Assis, 06.iv.2001, A.M.A. Lima col., 2 males, 9 females (DZUP); Santa Catarina. [Seara], Nova Teutônia, ix.1967, F. Plaumann col., 1 male (MZUSP).   
 Comments: Some specimens of this new species were collected on grass fields. It should be noted that, besides the adaptation to life to an open vegetationas noticed by Collin (1948: 227) and Stuckenberg (1971: 516) but queried by Shewell (1977) and Davies et al. (2012) the specimens were collected close to water source, preferably just before sunset.
description: Published as part of Lima, Ângela Maria Alves de & Silva, Vera Cristina, 2015, Four new Neotropical species of Trigonometopus Macquart, 1835 (Diptera, Lauxaniidae), pp. 131-142 in Papéis Avulsos de Zoologia (São Paulo) (São Paulo) 55 (9) on pages 133-135, DOI: 10.1590/0031-1049.2015.55.09, http://zenodo.org/record/4656507