Macrostomus amazonensis, Rafael, José Albertino & Cumming, Jeffrey M., 2015

Rafael, José Albertino & Cumming, Jeffrey M., 2015, Revision of the genus Macrostomus Wiedemann (Diptera, Empididae, Empidinae). IV. The amazonensis species-group, Zootaxa 3947 (1), pp. 109-121 : 114-115

publication ID	https://doi.org/ 10.11646/zootaxa.3947.1.7
publication LSID	lsid:zoobank.org:pub:54A83A1C-7F6E-416C-88C3-E4D3916E1698
DOI	https://doi.org/10.5281/zenodo.6106252
persistent identifier	https://treatment.plazi.org/id/1755937A-FFEC-9A59-FF47-FF63AF2382E0
treatment provided by	Plazi
scientific name	Macrostomus amazonensis
status	sp. nov.

Treatment

Macrostomus amazonensis View in CoL sp. nov.

( Figs 18–28 View FIGURES 18 – 28 , 58–59 View FIGURES 54 – 63 )

Diagnosis. Thorax entirely black, all coxae yellow. Abdomen including terminalia black. Male tergite 8 short, with shallow sinus anteriorly and deeper sinus posteriorly. Hypandrium with many paired setae medially and with acutely pronounced sinus on posterior margin. Female hind tibia with pinnate setae.

Description. Holotype male. Body length 2.6 mm; wing length 2.7 mm. Width of frons approximately ¾ anterior ocellus width. Antenna velvety black. Palpus brown. Thorax shiny black. Thoracic setae: 3–4 dorsocentrals, 3–4 antepronotals, 1–3 proepisternals, 2 pairs of scutellars. Legs shiny, predominantly yellow with apex of mid and hind femora, apex of fore and mid tibiae black; hind tibia and all tarsi black. Hind femur ( Fig. 18 View FIGURES 18 – 28 ) with 1 anteroventral seta at distal third. Wing ( Fig. 58 View FIGURES 54 – 63 , paratype). Halter light brown, knob partially white. Abdomen shiny black. Terminalia with tergite 8 short, with shallow sinus anteriorly and deeper sinus posteriorly ( Fig. 19 View FIGURES 18 – 28 ). Epandrium with anterodorsal and posterodorsal lobes of same height ( Fig. 20 View FIGURES 18 – 28 ). Anterior cercus subquadrate in lateral view; posterior cercus elongate vertically with secondary protuberances ( Fig. 20 View FIGURES 18 – 28 ). Cercal bridge ( Fig. 21 View FIGURES 18 – 28 ) small, connected with projection arising anteriorly from dorsal margin of anterior cercus. Ventral projection of cercus thin, with setae distally (as in Fig. 12 View FIGURES 10 – 17 of M. albicaudatus ). Hypandrium ( Fig. 22 View FIGURES 18 – 28 ) bearing many paired setae medially, basal pair longer, with sinus on posterior margin forming acute protuberance.

Female. Legs yellow to dark brown with coxae, trochanters and base of femora light yellow. Mid tibia ( Fig. 23 View FIGURES 18 – 28 ) with 1 slightly longer posterodorsal seta near middle. Hind tibia ( Fig. 24 View FIGURES 18 – 28 ) with longer pinnate setae along dorsal margin and shorter pinnate setae along basal third ventrally. Wing ( Fig. 59 View FIGURES 54 – 63 ). Terminalia with tergite 8 and sternite 8 almost same length ( Fig. 25 View FIGURES 18 – 28 ). Sternite 8 with cleft laterally, near middle ( Figs 25, 27 View FIGURES 18 – 28 ). Genital fork ( Fig. 28 View FIGURES 18 – 28 ) small, without lateral arms. Genital chamber slightly sclerotized.

Geographical distribution. Guyana, Brazil (Roraima, Amazonas, Pará, Rondônia, Mato Grosso).

Type Material. HOLOTYPE ♂: “ BRASIL, Am[azonas], Pq [Parque] Nac[ional] [do] Jau, Rio Unini, Democracia, 0 1 º 43'54''S – 61 º 54'32''W, 2–24.vi.1996 ”; “A.L.Henriques, J.Vidal & F.L.Oliveira, varredura”; “ Macrostomus amazonensis Holótipo ♂” (red label) ( INPA). PARATYPES. BRAZIL. Same data as holotype (2♂, 2♀ INPA, 2♂, 1♀ CNC); Amazonas, Rio Jau, Meriti, Novo Airão, 4–10.vi.1994, J.A. Rafael (1♂, 2♀ INPA; 1♂, 2♀ CNC); Tabatinga, 11–14.vii.1991, Socorro & Vidal (1♂, 1♀ INPA); Tefé, 15.vii.1991, Rafael & Vidal, varredura (3♂, 3♀ INPA; 1♂, 1♀ CNC); S. Izabel do Rio Negro, Maturacá, 11–13.x.1990, J.A. Rafael, arm. Malaise (1♂, 1♀ INPA; 1♂, 2♀ CNC); Roraima, Pacaraima, 5–8.iii.1988, Eq. J.A. Rafael, arm. Malaise, mata (1♂ INPA); Serra Pacaraima, BR 174, 0 4 º 27'04''N 61 º 07'56''W, varredura, J.A.Rafael & J.Vidal (2♀ INPA); Mato Grosso, 12 º 50'S 51 º 47'W, 20.iii.1968, O. W. Richards, R.S & R.G.S. Exped., B.M. 1968–260, swarm over log, dry forest (3♂, 5♀ BMNH); Rondônia, Ouro Preto do Oeste, Rio Boa Vista, 6–12.vii.1995, varredura, J.A. Rafael & J. Vidal (1♂ INPA); Pará, Serra Norte, Fofoca, 18.v.1984, T. Pimentel (1♀ MPEG). GUYANA. Colls. Richards & Smart, B.M. 1937–776, Mazaruni, high forest, 20.viii.1937 (1♀ BMNH).

Holotype condition. Pinned, in good condition, not dissected.

Etymology. In reference to the wide distribution in the Amazon Basin.

Variation. Two paratypes with 1 pair of scutellar setae.

Discussion. Macrostomus amazonensis sp. nov. appears most closely related to M. paraiba sp. nov. based on the cercal bridge of the male ( Figs 21 View FIGURES 18 – 28 , 32 View FIGURES 29 – 38 ) being connected to a projection that arises anteriorly from the dorsal margin of the anterior cercus (cercal bridge connected at ventral margin of anterior cercus in other species), the female bearing pinnate setae on the hind femur ( Figs 24 View FIGURES 18 – 28 , 34 View FIGURES 29 – 38 ), female sternite 8 with a lateral cleft near middle ( Figs 27 View FIGURES 18 – 28 , 37 View FIGURES 29 – 38 ), a small genital fork without lateral arms, and a slightly sclerotized genital chamber ( Figs 28 View FIGURES 18 – 28 , 38 View FIGURES 29 – 38 ).