Mesembrinella bicolor (Fabricius, 1805)

Whitworth, Terry L. & Yusseff-Vanegas, Sohath, 2019, A revision of the genera and species of the Neotropical family Mesembrinellidae (Diptera: Oestroidea), Zootaxa 4659 (1), pp. 1-146 : 110-111

publication ID	https://doi.org/ 10.11646/zootaxa.4659.1.1
publication LSID	lsid:zoobank.org:pub:57309E14-0330-4ED7-BCDA-355EE6618215
persistent identifier	https://treatment.plazi.org/id/03DA87E6-0F57-FFBB-FF19-BB9E31B1FACC
treatment provided by	Plazi
scientific name	Mesembrinella bicolor
status

Treatment

Key to species of the M. bicolor species-group

1 Postpronotal lobe with 3 setae........................................................................... 2

- Postpronotal lobe with 2 setae.......................................................................... 19

2 Stem vein setose dorsally ( Fig. 489 View FIGURES 489–497 )...................................................................... 3

- Stem vein bare dorsally................................................................................ 4

3 Wing yellowish along costa; subcostal sclerite with pubescence only; male frons narrow, 0.01 of head width at narrowest; female T6 of FU shape ( Fig. 314 View FIGURES 312–317 ); [known only from Brazil].......................................... M. peregrina

- Wing with dark infuscation along costa (similar to Fig. 2 View FIGURES 1–8 ); subcostal sclerite setose; male frons broader, 0.03–0.06 of head width at narrowest; female T 6 in WU shape ( Fig. 304 View FIGURES 300–305 ); [known from Argentina, Brazil, Ecuador, Paraguay, Peru; Marinho et al. (2017) also listed it from Bolivia, Colombia, French Guiana, Suriname and Venezuela]................ M. bellardiana

4 Wing with brownish to dark brown infuscation along costa (similar to Fig. 2 View FIGURES 1–8 )...................................... 5

- Wing hyaline (similar to Fig. 1 View FIGURES 1–8 ) or yellowish (not brown) along costa; basal area of wing may be darkened............. 13

5 Abdomen with heavy whitish tomentum and dark pit-like spots around setal sockets ( Fig. 103 View FIGURES 103–104 ); epiphallus of normal length; hypophallic lobes broad and of elongate oval shape in dorsal view ( Fig. 148 View FIGURES 145–152 ); female T6 of WV shape ( Fig. 303 View FIGURES 300–305 ); [known from Brazil, Ecuador and Peru; Marinho et al. (2017) also listed it from Colombia, Trinidad and Venezuela]........... M. batesi

- Abdomen without heavy whitish tomentum or dark pit-like spots; epiphallus of variable length; hypophallic lobes not broad, elongate and oval in dorsal view......................................................................... 6

6 Supravibrissal setae bright orange; setae on subcostal sclerite, if present, bright orange.............................. 7

- Supravibrissal setae usually brown or black; if orange, then very dark not bright; setae on subcostal sclerite, if present, not orange.............................................................................................. 8

7 All legs reddish; wing with section IV 0.63 of section III; epiphallus of normal length ( Fig. 187 View FIGURES 183–192 ); hypophallic lobes very narrow in dorsal view ( Fig. 188 View FIGURES 183–192 ); [known only from Venezuela]..................................... M. velasquezae sp. nov.

- Mid and hind tibiae and tarsi black or dark brown; wing with section IV 0.82 of section III; epiphallus unusually short ( Fig. 161 View FIGURES 153–162 ); hypophallic lobes broad and pear-shaped in dorsal view ( Fig. 162 View FIGURES 153–162 ); [known from Brazil, Ecuador and Peru; Marinho et al. (2017) also listed it from Bolivia and Colombia].................................................. M. currani

8 A large fly (usually 16–17 mm); section IV of wing 0.50 of section III or more.................................... 9

- A small to medium-sized fly (8–12 mm); section IV of wing 0.35 of section III or less, except 0.44 in M. serrata ........ 10

9 Palpus yellow; discal scutellar setae present; section IV of wing 0.51 of section III; face dark; wing with veins in posterior half outlined with dark shading; epandrium, cerci and surstyli as in Figs 81–82 View FIGURES 81–86 ; [known only from Bolivia; Marinho et al. (2017) also listed it from Colombia and Costa Rica]..................................................... M. pictipennis

- Palpus brown; discal scutellar setae absent; section IV of wing 0.75 of section III; face yellowish; wing veins in posterior half only faintly shaded; epandrium, cerci and surstyli illustrated in Guimar„es (1977: figs 70, 87); [known only from Colombia]......................................................................................... M. apollinaris

10 Wing with section IV more than 0.30 of section III; hypophallic lobes in dorsal view with distinctive coarse serrations ( Figs 156 View FIGURES 153–162 , 180 View FIGURES 173–182 )........................................................................................... 11

- Wing with section IV less than 0.25 of section III; hypophallic lobes with finer serrations dorsally ( Figs 178 View FIGURES 173–182 , 184 View FIGURES 183–192 )....... 12

11 Wing with dark infuscated area along costa to R 2+3; a larger fly, about 12 mm in length; mid and hind femora with basal 1/4 to 1/2 brown and apical half of lighter, yellow-orange color [slightly darker in one specimen]; ac usually 2:3 or 2:2; wing with section IV 0.31 of section III; epiphallus very short ( Fig. 155 View FIGURES 153–162 ); hypophallic lobes narrow in dorsal view ( Fig. 156 View FIGURES 153–162 ); female T6 of OV shape ( Fig. 307 View FIGURES 306–311 ), without suture midway; [known only from Bolivia and Peru]..................... M. brunnipes

- Distal 2/3 of wing faintly infuscated along costa; a smaller fly, around 9 mm in length; all femora entirely orange; ac 2:1; wing with section IV 0.44 of section III; epiphallus of normal length ( Fig. 179 View FIGURES 173–182 ); hypophallic lobes broad and pear-shaped in dorsal view ( Fig. 180 View FIGURES 173–182 ); female T6 of WV shape ( Fig. 319 View FIGURES 318–323 ), with suture midway; [known only from Peru]....... M. serrata sp. nov.

12 Tibiae and tarsi brown; abdomen with distinct oblique pale streaks of tomentum; ac usually 2:3; male frons 0.015 of head width at narrowest; female T6 of OV shape ( Fig. 321 View FIGURES 318–323 ); [known only from Brazil ( Marinho et al. 2017), Peru and Bolivia]................................................................................................. M. townsendi

- Tibiae orange; abdomen with some pale tomentum, but not in oblique streaks; ac usually 2:1; male frons 0.063 of head width at narrowest; female T6 of WU shape ( Fig. 318 View FIGURES 318–323 ); [known only from Brazil]........................... M. semihyalina

13 Wing with distinct yellowish area along costa or entirely yellowed............................................. 14

- Wing usually hyaline or with very faint yellowing, primarily along costa........................................ 16

14 Subcostal sclerite bare; discs of upper and lower calypters pale; rim of upper calypter dark with pale setae, rim of lower calypter pale with long pale setae; wing with section IV 0.28 of section III; [widespread and common; Mexico and Central and South America except Argentina and Chile ( Marinho et al. 2017)]............................................. M. bicolor

- Subcostal sclerite setose; wing section IV 0.45 or more of section III........................................... 15

15 Scutellum without discal setae; abdomen entirely shiny purple-blue; wing with heavy yellowing along costal margin, whole wing yellowish except cell r 4+5 with clear oval in middle; upper and lower calypters reddish; rim of upper calypter dark with short reddish setae, rim of lower calypter pale with long reddish setae; epandrium with fine dark setae ( Fig. 95 View FIGURES 93–98 ); phallus in dorsal view without curved horn-like structures projecting from sides of basiphallus; hypophallic lobes narrow ( Fig. 186 View FIGURES 183–192 ); female T6 of WV shape ( Fig. 322 View FIGURES 318–323 ); [widespread in Central America and northern South America].................. M. umbrosa

- Scutellum with discal setae; abdomen bluish, with heavy whitish tomentum and dark pit-like areas around setal sockets (similar to Fig. 103 View FIGURES 103–104 ); wing mostly hyaline, with yellow area only along costa; upper and lower calypters pale; rim of upper calypter slightly darkened, with short pale setae, rim of lower calypter pale with long pale setae; epandrium with stout black setae ( Figs 69–70 View FIGURES 69–74 ); phallus in dorsal view with long curved posterior directed horn-like structures projecting from sides of basiphallus; hypophallic lobes broad and oval-shaped ( Fig. 160 View FIGURES 153–162 ); female T6 of RV shape ( Fig. 309 View FIGURES 306–311 ); [known from French Guiana and Brazil].................................................................................... M. chantryi sp. nov.

16 Postpronotal lobe and femora orange..................................................................... 17

- Postpronotal lobe and femora bluish..................................................................... 18

17 Subcostal sclerite setose; thorax with 2:2 or 2:3 ac, 1 ia, kat 2:1; male frons 0.08 of head width at narrowest; male T3 a triangle of bluish cuticle from hind margin to point in middle of tergite ( Fig. 493 View FIGURES 489–497 ); surstylus and cercus robust ( Figs 91–92 View FIGURES 87–92 ); epiphallus normal ( Fig. 181 View FIGURES 173–182 ); female T6 of OV shape; [known from Central America and northern South America]......... M. socors

- Subcostal sclerite bare; thorax with 2:1 ac, 0 ia, kat 1:1; male frons 0.025 of head width at narrowest; T3 without a triangle of bluish cuticle on hind margin; surstylus and cercus slender ( Figs 75–76 View FIGURES 75–80 ); epiphallus very short ( Fig. 165 View FIGURES 163–172 ); female T6 of in WV shape ( Fig. 312 View FIGURES 312–317 ); [known from Costa Rica and Panama]............................................. M. flavicrura

18 T5 with dense, irregular, long and slender setae; kat 2:1; male frons 0.04 of head width at narrowest; epandrium, cerci and surstyli distinctive: surstylus long and straight in lateral view, cercus even longer and also straight ( Fig. 77 View FIGURES 75–80 ); in posterior view, surstyli much shorter than cerci and apically curved outward, basal two-thirds of cerci narrow, parallel-sided ( Fig. 78 View FIGURES 75–80 ); phallus in dorsal view exceptionally narrow ( Fig. 168 View FIGURES 163–172 ). Female T6 of OV shape ( Fig. 313 View FIGURES 312–317 ); [known only from Bolivia]............................................................................................. M. longicercus sp. nov.

- T5 with shorter, sparser setae; kat 1:1; male frons broader, 0.09 of head width at narrowest; epandrium, cerci and surstyli in lateral view with surstylus very short, slightly curved backward, and cerci much longer than surstyli ( Fig. 67 View FIGURES 63–68 ); in posterior view, basal half of cerci bulbous, apical half abruptly narrowing to tip ( Fig. 68 View FIGURES 63–68 ); phallus in dorsal view broader ( Fig. 158 View FIGURES 153–162 ); female T6 of RV shape ( Fig. 308 View FIGURES 306–311 ); [known only from Bolivia]............................................ M. bullata sp. nov.

19 Wing entirely hyaline; male frons narrow, 0.06 of head width at narrowest; female T6 of WV shape ( Fig. 305 View FIGURES 300–305 ); [known from French Guiana, Guyana, Peru and Venezuela; Marinho et al. (2017) also listed it from Brazil]................. M. benoisti

- Wing with more or less dark infuscation along costa; male frons broader, 0.08–0.12 of head width at narrowest.......... 20

20 Wing with weak infuscation along costa; T1+2–T4 with bluish-purple horizontal bands on posterior margins (best seen in well-preserved specimens); ac 0:2; rim of upper calypter sooty; female T6 of OV shape ( Fig. 311 View FIGURES 306–311 ); [known only from Brazil; Marinho et al. (2017) also listed it from Colombia].............................................. M. cyaneicincta

- Wing with dark infuscation along costa; T1+2-T4 without horizontal bands on posterior margin; ac 0:1; rim of upper calypter light or dark........................................................................................ 21

21 T4 with complete row of marginal setae; posthumeral seta absent; upper calypter with pale rim; male frons 0.10 of head width at narrowest; female T6 of WV shape; T7 narrowed midway ( Fig. 316 View FIGURES 312–317 ); [known from Bolivia, Brazil, Guyana, Peru and Venezuela; Marinho et al. (2017) also listed it from Colombia and Venezuela]........................... M. quadrilineata

- T4 without row of marginal setae; posthumeral seta present, sometimes small; upper calypter with dark rim; male frons narrower, 0.08 of head width at narrowest; female T6 of FU shape; T7 broad midway ( Fig. 317 View FIGURES 312–317 ); [known from Bolivia, Brazil, Guyana and Peru].............................................................................. M. randa