Review of the Nearctic genus Wilcoxia James (Diptera: Asilidae: Stenopogoninae) with descriptions of three new species
Author
Pollock, Darren A.
Author
Reichert, Lisa A.
text
Zootaxa
2019
2019-11-12
4695
5
401
437
journal article
24897
10.11646/zootaxa.4695.5.1
34f39440-da4f-4f5e-b9bf-258a7445ce73
1175-5326
3542536
A6844BF7-1B08-40D8-AB38-37F1E93B434C
7.
Wilcoxia forbesi
Pollock & Reichert
,
n. sp.
(
Figs 13–14
,
23–24
,
34–35
,
38, 40
,
56
,
65
,
78–80
)
Holotype
(here designated), male, labeled: “N.
MEX
.
Dona Ana Co.
1miNW Tortugas Mt. 4100’ (E of
Jct.
,
Univ.
and
Telshore
)
G. Forbes
20 NOV 1983
//
NMSU
// [red label]
HOLOTYPE
♂
Wilcoxia forbesi Pollock & Reichert
”, in CAS
.
Allotype
, female, labeled: “N.
MEX
.
Dona Ana Co.
1miNW Tortugas Mt. 4100’ (E of
Jct.
,
Univ.
and
Telshore
)
G. Forbes
20 NOV 1983
// 21119 // [green label]
NMSU
// [red label]
ALLOTYPE
♀
Wilcoxia forbesi Pollock & Reichert
”, in CAS
.
Paratypes
, from the following localities (all with light blue “
PARATYPE
Wilcoxia forbesi
,
n. sp.
Pollock
&
Reichert
” labels):
UNITED STATES OF AMERICA
.
New Mexico
.
Doña Ana Co.
Dunes 4400’
1.3 mi
NW jct C7/C8,
NW of Corralitos
[
32.295362
,
-107.038391
],
4.xi.1984
,
G. Forbes
, gravel, (
NMSU
,
4♂
,
6♀
), (
CASC
,
1♀
)
;
1 mi
NW Tortugas Mt.
, 4100’ (E. of
Jct.
,
Univ.
and
Telshore
) [
32.302989
,
-106.708571
],
11.xi.1984
,
G. Forbes
, (
NMSU
,
2♂
,
3♀
)
;
same locality,
20.xi.1983
, G.S.
Forbes
, (
CASC
,
1 ♂
,
4♀
;
BYUC
,
1♀
)
;
same locality,
15.xi.1983
, G.
Forbes
, (
NMSU
,
1♀
,
EMFC
,
1♂
)
;
3.2 mi
E
Tortugas Mt.
[
32.292071
,
-106.640091
], 4300’,
11.xi.1984
,
G.S. Forbes
, (
NMSU
,
1♂
)
;
N. Base
,
Tortugas Mt.
[
32.297363
,
-106.697996
], 4200’,
1.xi.1984
,
G.S. Forbes
, (
NMSU
,
7♂
,
2 ♀
;
BYUC
,
1♂
)
;
5.1 mi.
E.
Tortugas Mt.
[est. at
32.291374
,
-106.594039
], 5000’,
13.xi.1982
,
G.S. Forbes
, (
EMEC
,
2♀
[
EMEC 1135
625, 1135628];
NMSU
,
1♂
)
;
same locality,
3.xi.1985
, G.S.
Forbes
, (
NMSU
,
2♂
,
3♀
)
;
4 mi
E.
Tortugas
Mtn. [
32.290898
,
-106.627066
],
4.i.1985
,
D. Lightfoot
&
G.S. Forbes
, (
NMSU
,
1♂
,
1♀
)
;
4 mi
NE of Tortugas Mt.
[
32.332278
,
-106.647555
],
4800 ft.
,
20.i.1985
, D.
Lightfoot
, (
NSMU
,
1♀
)
;
Tortugas
Mtn., nr.
Las Cruces
,
32.296075
,
-106.706497
[
32.296075
,
-106.706497
],
4245 ft.
,
3.i.2017
,
D. & G. Pollock
,
L. Reichert
, collected on small to medium rocks on rocky/stony terrain, (
ENMU
,
15♂
,
13♀
)
;
same locality and data,
4.i.2017
, (
ENMU
,
5♂
,
10♀
)
;
Jornada
LTER site, 1.0 mi SE
College Rch
[
32.519662
,
-106.791872
], 4400’,
28.x.1984
,
G.S. Forbes
, (
NMSU
,
2♂
)
;
Jornada
LTER site,
1 mi
SW College Rch
[
32.520249
,
-106.816191
], 4300’,
1.xii.1984
,
G.S. Forbes
, (
NMSU
,
2♂
)
;
Jornada
Range,
2 mi
SW Coll Rch
HQ [
32.510074
,
-106.828202
], 4500’,
7.xi.1983
,
D. Lightfoot
, (
NSMU
,
1♂
)
;
Doña Ana Mts.
, 4700’,
6.6 mi
N rt. 70/82,
2.4 mi
W Jornada
rd [
32.475142
,
-106.777375
],
28.xi.1981
,
G. Forbes
, (
NMSU
,
1♂
,
1♀
)
.
Otero Co.
32°75260N, 105°92825W [
32.75260
,
-105.92825
],
4187 ft.
,
xi.2010
,
B. Barker
, (
EMFC
,
3♂
,
3♀
)
.
Texas
.
Reeves Co.
Rt. 290,
3.6 mi
W. jct at
Toyahvale
[
30.941876
,
- 103.847704
],
8.xii.1985
,
G. Forbes
, (
NMSU
,
1♀
)
.
Derivation of specific epithet
: named in honor of Gregory S. Forbes, assiduous collector of robber flies in New
Mexico
, including most specimens of this new species.
Diagnosis
. This species may be separated from the other three members of the
martinorum
group (of which it is the most distinct) by the following characters: sexes dimorphic: abdomen of females with pattern of pollinose and non-pollinose areas, males with abdomen uniformly pollinose; costa incomplete, only traceable to near junction of CuA
2
and wing margin; halter knob pink, distinctly contrasting yellow stem; mystax of male very dense (
Figs 13
,
23
); femora entirely bare, without pollinose patch(es).
Description
.
Male
(
Fig. 13
). TL
4.4–7.1 mm
; wing
4.4–5.6 mm
.
Head
(
Fig. 23
) black, covered in pale grey tomentum; face (in profile) projecting slightly beyond eye; hairs and setae of head white; lower occipital hairs long, very dense, “wispy”;
ocellar tubercle
with many long, fine setae and some hairs (ca. length of postpedicel + style);
mystax
(
Fig. 23
) very dense, consisting of very long hairs (> length of antenna), occupying almost entire face; hairs white, bases perpendicular to slightly less than 90° from plane of face; no distinct hairs on face separate from mystax;
palpi and proboscis
black with white hairs;
antennomeres
brown to black, pollinose, scape thinly pollinose; scape and pedicel with long ventral setae (pedicel with one longer hair/seta) and hairs, and several relatively short hairs dorsally;
ratio of antennomere lengths
(scape: pedicel: postpedicel: style + spine) = 6: 6: 14: 9.
Thorax
black, covered in pale grey tomentum;
scutum
with median stripe absent, marked in some individuals by linear areas of sparser tomentum; acrostichal setae present, though difficult to discern from long hairs, 5–6 per row; scutum surface uniform, without distinct non-pollinose or differently colored spots; scutum with moderately dense pile of long white hairs (> length of postpedicel), length and density subequal pre- and postsuturally; most specimens with 3 notopleural setae, 2 supraalar setae, and 1 postalar seta; stoutest thoracic setae with amber cast;
scutellum
uniformly pale grey pollinose; 6–8 white marginal setae, longest setae greater in length than scutellum, perpendicular to plane of scutellum; very few short marginal hairs present; disc of scutellum with few shorter, partially appressed hairs;
pleura
pale grey pollinose;
katatergite
with about 20 long fine white setae, tips “crinkly”;
wings
hyaline; costa incomplete, present to near apex of anal lobe only (
Fig. 38
); microtrichiae sparse and incon- spicuous on entire wing (
Fig. 40
);
halter
with base brown and yellow, stem yellow, knob pink to light purple;
legs
(
Figs 13–14
) uniformly black, entirely bare, without pollinosity on femora; hairs and setae white; femora dorsally with moderately dense, white appressed hairs (<femur width) and a few longer, suberect setae (> femur width); ven- trally with longer, suberect white hairs (longest ca. femur width); tibiae with relatively dense, short (<tibia width) appressed white hairs, ventrally with a few longer (longest> tibia width), suberect hairs, slightly more abundant on front tibiae; mesotibial spine very light yellow; protibiae without sigmoidal spine.
Abdomen
(
Figs 13
,
34
) black, tergites 2–7 densely pale grey pollinose, pollinosity slightly less dense anteriorly on tergites; hairs white; tergite 1 bare dorsocentrally, bare patch widened anteriorly; tergite 2 bare anterior of punctillae and with bare narrow posterior margin; tergite 3 with bare narrow posterior margin;
sternites
pale grey pollinose, with moderately long, fine white hairs, slightly longer on anterior sternites.
Male genitalia
(
Fig. 56
). Apex of dorsal gonocoxite process relatively shallowly bifid, inner lobe distinctly longer than outer, carina on outer lobe absent; dorsal process extending past apex of ventral gonocoxite process; medial gonocoxite processes moderately thin, moderately curved towards phallus; gonostylus relatively thin, arcuate, apex not truncate; phallus without distinct, subapical denticle on lateral margins; lateral margins evenly narrowed to apex.
Female
(
Fig. 14
). TL 5.0–
7.2 mm
; wing
4.2–6.3 mm
. Features similar to male, except for the following: pale grey pollinosity of head and thorax with very light to medium brown tint; mystax (
Fig. 24
) much sparser than male, but most hairs still ca. length of antennae; abdomen (
Figs 14
,
35
) dorsally largely bare, shiny black, pale grey pollinosity confined to lateral areas of tergite 1; tergite 2 with narrow band of pollinosity anterior of punctillae, lateral margins and posterolateral margins extending medially on posterior margin but not connecting, leaving center of posterior margin non-pollinose; tergites 2–5 with pollinosity in anterior band, and on lateral margins, expanded dorsomedially, leaving center of posterior margin non- or thinly pollinose; tergite 6 bare, in some specimens with some pollinosity, confined to extreme lateral margins; tergite 7 bare; sternites 2–5 pollinose, 6 lightly pollinose, confined to anterolateral margins; sternite 7 bare.
Notes.
Couplet
28 in
Wood’s (1981)
key that leads eventually to
Wilcoxia
mentions “C [costa] continuing around posterior wing margin to wing base”. Because the costa is abbreviated in individuals of
W
.
forbesi
, the second part of the above couplet is not completely accurate. The first part of the couplet leads to genus
Itolia
Wilcox
, based on peculiarities of the wing venation and shiny areas on the scutum.
Natural history
. On
3–4 January 2017
, specimens of
W
.
forbesi
were collected on the rocky terrain at the base of
Tortugas
Mtn., near Las Cruces, Doña Ana Co., NM (
Figs 78–80
). Flies were observed on small (
6 inch
maximum dimension) to medium-large rocks (
1–2 foot
maximum dimension, e.g.
Fig. 80
). Sweeping was done in this area also, but no flies were collected on vegetation. Among the
43 specimens
(
20 males
,
23 females
) collected on these two days, 11 (
3 males
,
8 females
) were taken with associated prey. Ten of these were winged males of a species of scale insect [
HEMIPTERA (Sternorrhyncha)
:
Margarodidae
:
Margarodes
sp.] and one was a small fly (
DIPTERA
:
Drosophilidae
). Bulk index of the prey items ranged from 0.4–1.4; ratio of bulk index of predator:prey ranged from 8.3–27.4 (average = 16.2). Specimens were collected from
28.x–20.i.
Distribution
(
Fig. 65
). As mentioned above for
W
.
apache
, the distribution of
W
.
forbesi
is sympatric with the western “cluster” of
W
.
apache
. Almost all specimens of
W
.
forbesi
were collected in Doña Ana County, near Las Cruces. Elevations range from
3,490 to 5,382 feet
.