Taxonomy, cladistics and biogeography of the South American genus Brachygasterina Macquart (Diptera: Muscidae)AuthorDe Carvalho, C. J. B.AuthorPont, A. C.textZootaxa20061151126journal article5063110.5281/zenodo.1721532ad9bd9e-c42b-4deb-86bf-3ad2ee1ad19811755326172153Brachygasterina stuebeli
(
Röder, 1886
)
(
Figs 3
,
8
,
16
)
Hydrotaea stuebeliRöder, 1886
: 269
.
Diagnosis
This species can be easily
distinguished by the very long
and dense hairs on the eye,
by the setulae on facial ridges
reaching almost to the level of
aristal insertion, and by the
slightly upcurved vein M.
Redescription
Female. Head: frons broad, at narrowest point 0.34–0.36 of head width (
Fig. 3
). Eye with long and dense hairs (
Fig. 8
); when the head is viewed from the front, the hairs are about as long as width of frontoorbital plate (
Fig. 3
). Frontoorbital plate matt, blackish; parafacial, face and gena brownishgrey pruinose; occiput metallic blue to violet. 7–8 pairs of frontal setae; 1 strong and 1–2 weak reclinate orbital setae. Facial ridge with setulae reaching almost to level of aristal insertion. Parafacial and gena broad, in lateral view the former at least 0.5 of first flagellomere width (
Fig. 8
). Proboscis mainly shining, dusted behind. Palpus black.
Thorax. Groundcolour subshining dark metallic violetblue, dulled by pruinescence in posterior view. Mesonotum with 2 stripes (very indistinct in
lectotype
). 2+3 developed acrostichals (3+
3 inlectotype
); 2 strong posterior intraalar, first weaker; prealar strong, subequal to anterior notopleural seta; notopleuron with dense setulae, mostly around second notopleural seta. Scutellum laterally setulose; with strong apical, basal and lateral setae, and corresponding setae on disc. One strong proepisternal seta and 3–4 hairs; 2 strong proepimeral setae and many long hairs. Katepisternals 2+3. Meron bare. Katatergite distinctly setulose.
Legs. Dark brown. Fore tibia without posterior seta. Mid femur with 2 short anterior and 4 posterior preapical setae. Mid tibia with 3 posterior setae, without anterodorsal or ventrals.
Hind
femur with a row of strong anteroventral setae, and with strong posteroventrals in basal half; 2–3 anterodorsal and 3 anteroventral setae; dorsal preapical strong, anterodorsal preapical weak, without posteroventral apical.
Wing. Smoky, veins dark brown. Veins bare, except costa. Crossvein dmcu very sinuous. Vein M slightly upcurved towards R4+5. Calypters dark brown, lower one slightly longer than upper one. Knob of haltere dark brown.Abdomen. Subshining metallic blueviolet, matt in posterior view. Sternite 1 bare.
Ovipositor: see
Fig. 16
.
Measurements (n=2): Body length, 8.0–
8.7 mm
. Wing length,
7.8–8.3 mm
.
Lectotype
: body
10 mm
, wing
9 mm
.
Type
material examined
Lectotype
, female (see notes on
type
locality below), in
MLUH
, by present designation and labelled accordingly; it is the only surviving
syntype
. Old white handwritten label: “Paramo / 3600 Met. /
Columbia
” [the “
Columbia
” in a different hand from the rest, and neither in Von Röder’s handwriting]; Von Röder’s handwritten white label: “Hydrotae / a / Stübeli / n. sp.”. Labelled (printed) by ACP: “
LECTOTYPE
female /
Hydrotaea
/
stuebeli
/ Von
Röder, 1886
/ des.
A. C. Pont 2004
” (see also
Pont 2004
).
Other material examined.
ECUADOR
. Pichincha,
35 km
Tandopi,
24–29.vi.1975
(S. Peck),
1 female
(
FMNH
); Napo,
42 km
NW Baeza, 3300’ [feet],
2–6.iii.1976
(S. Peck),
1 female
(
DZUP
).
Remarks
The body of the
lectotype
is rather dirty and right fore leg is missing, otherwise it is well preserved. According to the labels, the other specimens were collected in carrion traps and on bamboo shrubs between 1100 and 3600 metres, the latter on páramo.
Notes on the typelocality: The
Diptera
collected by Alphons Stübel, one of greatest of the early collectors in South
America
, were identified and published by
Röder (1886)
. Stübel spent nine years in this region after arriving in Santa
Marta
,
Colombia
, in 1868. He subsequently visited several other countries, mainly studying geology and especially vulcanology but also collecting flies (see
Papavero 1973
). Compared with the present time,
Colombia
was a very different country when Stübel collected the female of
B. stuebeli
at an altitude of 3600 metres, embracing the whole northwest part of the South American continent. The
lectotype
label mentions Páramo in
Colombia
as the typelocality. However, “Páramo” is a
type
of vegetation, subdivided into subpáramo, páramo and super páramo (
Hammer 1974
), and is characteristic of the South American tropical highlands, being found above 3000 metres in northern
Peru
,
Ecuador
,
Colombia
and
Venezuela
. It seems probable that the “Páramo” of the
lectotype
label refers to the vegetation
type
and is not the name of town or city in
Colombia
.
According to
Papavero (1973: 310)
, Stübel made an excursion to Quito (
Ecuador
) and its neighbourhood from
April to June 1871
, and in
May
,
June
,
October to December 1873
to several localities in
Ecuador
, including Páramo de Calacali at 3600 metres. This is the only locality where “Páramo at 3600 metres” is clearly stated (see
Papavero 1973
), although there were other localities at or above 3600 metres during this entire journey. It is difficult, if not impossible, to establish the typelocality of
B. stuebeli
with certainty, but on the basis of Stübel’s 1873 itinerary we propose to fix Páramo de Calacali in
Ecuador
as the typelocality of
B. stuebeli
(map,
Fig. 19
). Other localities in
Ecuador
for
B. stuebeli
are known to us (see the material listed above).
Geographic distributionEcuador
.