Risa Becker 1907
Creators: name: Mathis, Wayne N.
name: Zatwarnicki, Tadeusz
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Ephydridae
Risa

description: Key to species of Risa Becker   
1 Palpus yellow............................................................................................................................ 2  
—— Palpus black............................................................................................................................... 3  
 2 Forecoxa black. Ocellar triangle short, slightly protruding beyond middle of frons. Postocellar setae present.................................... R. flavipalpis Ozerov   
 —— Forecoxa yellow. Ocellar triangle long, reaching lunule. Postocellar setae absent.............................................................. R. flavicoxa Krivosheina & Ozerov   
3 Fronto-orbital setae 3 (rarely 2 or 4), proclinate, small, hair-like, equal or subequal in size (Figs 22, 38, 39, 49, 50, 57–60)........................................................ 4  
—— Anterior fronto-orbital seta about 2–3 times longer than middle fronto-orbital seta, inclinate; posterior fronto-orbital seta usually reclinate, occasionally proclinate, usually as long as anterior fronto-orbital setae, occasionally as long as middle fronto-orbital seta (Figs 21, 26, 27)........................................................................................... 9  
4 Labellum about twice length of ventral margin of head in lateral view (Figs 24, 46)...................................................................................................................... 5  
 —— Labellum about 1–1.5 times length of ventral margin of head (Figs 23, 25, 40, 41, 58)............................................................................................................ 8 5 Prescutellar acrostichal setae well developed; scutellar disk bearing scattered, sparse setulae; setulae along costal margin numerous; large species (length about 2 mm)............................................... R. asiatica Ozerov   
—— Prescutellar acrostichal setae greatly reduced or lacking (Fig. 37, 59–60); scutellum lacking setulae; setulae along costal margin sparse; smaller species (length about 1–1.5 mm)...................................................................... 6  
 6 Scutum distinctly microtomentose; setulae along costal margin more numerous and denser (24–34 on distalmost section). Halter knob with large dark spot.......................................................... R. brevicornis Papp comb. nov.   
—— Scutum indistinctly microtomentose; setulae along costal margin fewer and sparser (11–16 on distalmost section). Halter knob entirely yellow or with large dark spot............................................................................. 7  
 7 Antenna and arista predominantly brownish (Fig. 37). Halter knob yellow...................................................... R. salsolae (Mathis & Zatwarnicki) comb. nov.   
 —— Antenna predominantly or entirely yellow, scape and pedicel and basal flagellomere anteroapically occasionally darker, arista yellow to brown (Figs 49, 50). Halter knob with large dark spot........................................................................................................... R. nettae sp. nov.   
 8 Face nearly flat, without prominent shallow/low carina (Fig. 58); antenna elongate, basal flagellomere ratio 1.75; scutum distinctly microtomentose (Figs 59, 60); lower portion of frons, parafacial and lateral margin of face conspicuously and finely whitish to silvery microtomentose (Figs 57, 60)............................................................ R. kotrbae sp. nov.   
 —— Face with distinct carina (Figs 38, 39); antenna short, basal flagellomere ratio 1; scutum practically without microtomentum; lower position of frons, parafacial and lateral margins of face almost bare of microtomentum, shiny (Figs 38, 39)............................................................................................ R. brevirostris sp. nov.   
 9 Proboscis short, labellum about 1.25 times length of ventral margin of head (Fig. 25); antenna elongate, basal flagellomere ratio 2.5–3 (Fig. 25)................................................................................... R. longicornuta Papp   
 —— Proboscis long, labellum about 1.5 times length of ventral margin of head (Figs 23, 40, 41); antenna shorter, basal flagellomere ratio 2 (Figs 23, 26, 27)............................................................................ R. longirostris Becker
description: Published as part of Mathis, Wayne N. & Zatwarnicki, Tadeusz, 2023, Phylogeny and Taxonomy of the Risa Genus-group (Diptera: Ephydridae), with Description of a New Genus from Australia, pp. 1-23 in Records of the Australian Museum (Rec. Aust. Mus.) (Rec. Aust. Mus.) 75 (1) on pages 12-13, DOI: 10.3853/j.2201-4349.75.2023.1823, http://zenodo.org/record/7946210