A revision of the Patagonian predaceous midges of the subgenus Acanthohelea of Stilobezzia excluding the S. (A.) edwardsi group (Diptera: Ceratopogonidae)
Author
Cazorla, Carla G.
Author
Spinelli, Gustavo R.
text
Journal of Natural History
2014
2014-06-30
49
3
155
209
journal article
21098
10.1080/00222933.2014.939728
9de6d04b-eb21-45ec-b287-c368c1106b40
1464-5262
4002623
Stilobezzia
(
Acanthohelea
)
mapuche
, Cazorla and Spinelli
sp. nov.
(
Figures 4
,
18
)
Diagnosis
The only Patagonian species of
Stilobezzia
(
Acanthohelea
)
with gonostylus greatly curved subbasally over 90°, aedeagal sclerites heavily sclerotized, slender to mid length and the distal half broadening abruptly and mesally directed with subapical pointed divergent prongs. Female unknown.
Male.
Head (
Figure 4A
). Dark brown. Antennal flagellum brown, plume dark brown, dense; flagellomeres 1–10 with pale ring above the insertions of the plume setae; antennal ratio 1.51–1.75 (1.58,
n
= 5). Palpus brown; segment 3 as long as 5; palpal ratio 3.00–3.50 (3.20,
n
= 6).
Thorax. Scutum uniformly dark brown; scutellum pale with 6 large setae; postscutellum dark brown. Legs brown, hind leg slightly darker than mid and forelegs; hind tibial comb with 8 spines; prothoracic TR 1.70–1.87 (1.79,
n
= 8); mesothoracic TR 1.91–2.10 (2.02,
n
= 8); metathoracic TR 1.72–2.00 (1.86,
n
= 8). Wing (
Figure 4B
) length 1.39–1.66 (1.50,
n
= 10) mm, width 0.49–0.58 (0.54,
n
= 10), costal ratio 0.68–0.73 (0.71,
n
= 10); membrane slightly infuscated; second radial cell 2.41–3.36 (2.78,
n
= 8) × longer than first; cubital fork originating slightly distal to level of base of r-m cross vein; macrotrichia on costa, R
1
, R
2
, R
3
, M
1,
M
2,
Cua
2
, sparse on distal 1/ 3 of cells r
3
, m
1
, m
2
. Halter pale brown.
Figure 4.
Stilobezzia
(
A.
)
mapuche
Cazorla and Spinelli
sp. nov.
, male: (A) head; (B) wing; (C) genitalia (ventral view), aedeagus and parameres removed. Scale bars 0.05 mm.
Abdomen. Dark brown. Genitalia (
Figure 4C
): tergite 9 triangular, tapering abruptly distally, extending 0.80 length of gonocoxites, posterior margin rounded; sternite 9 2.45× broader than long, posterior margin straight; sternite 10 triangular, margins wrinkled, produced beyond base of cerci; cerci moderately slender, broadly divergent. Gonocoxite 2.05× longer than greatest breadth; gonostylus 0.72× length of gonocoxite, base stout, greatly curved subbasally over 90°, tip pointed. Parameres subparallel; basal apodemes slender, stem stout, tip bulbous. Aedeagus 0.77× length of basal breadth, composed of two convergent sclerites, each with stem slightly curved, heavily sclerotized, slender to mid length, distal half broadening abruptly, directed mesally with subapical pointed divergent prongs arising from common base, proximal prong directed laterad, distal one directed distad.
Female.
unknown.
Distribution
Argentina
(
Neuquen
,
Río Negro
)
,
Chile
(
Santiago
) (
Figure 18
)
.
Types
Holotype
male,
Argentina
,
Río Negro prov.
,
Parque Nacional Nahuel Huapi
,
río Manso
superior,
41°14
′
28.4
″
S
,
71°44
′
12.6
″
W
,
837 m
,
7 February to 2 March 2007
, A. Garré-
F.
Montes de Oca
,
Malaise trap
(
MLPA
)
.
Paratypes
:
15 males
, as follows: same data as holotype
,
2 males
(one in
CNCI
, one in
USNM
); same data except
41° 14
′
814
″
S
,
71°46
′
58.5
″
W
,
845 m
,
2 males
; laguna
Los Clavos
,
41°04
′
48.6
″
S
,
71°49
′
33.9
″
W
,
1194 m
,
5 February to 3 March 2007
, A.
Garré
–
F. Montes de Oca
,
3 males
(one in
BMNH
),
Malaise trap
;
Parque Nacional Nahuel Huapi
, laguna
Mercedes
,
40°52
′
43.4
″
S
,
71°34
′
41
″
W
,
899 m
,
3–21 January 2008
, A.
Garré
–
F. Montes de Oca
,
1 male
,
Malaise trap
;
Neuquen prov.
,
Parque Nacional Nahuel Huapi
, mallin
La Heladera
,
41°00
′
6.4
″
S
,
71°49
′
40.3
″
W
,
878 m
,
7 January to 4 February 2007
, A.
Garré
–
F. Montes de Oca
,
6 males
,
Malaise trap
;
Chile
.
Santiago prov.
,
Quebrada de La Plata
,
Maipú
33°30
′
S
,
70°55
′
W
,
26 April 1966
, M. E.
Irwin
,
1 male
, Malaise trap.
Etymology
The name
mapuche
refers to Mapuche Indians, early inhabitants of southern and central
Chile
and north-western Argentinean Patagonia.
Discussion
This species is somewhat similar to
S
.
(
A
.)
pabloi
. The latter species is clearly distinguishable by the aedeagal sclerites with sclerotized tip with a small mesal notch.