Revision of the Nearctic species of the genus Pholetesor Mason (Hymenoptera: Braconidae)
Author
Whitfield, James B.
text
Zootaxa
2006
2006-03-10
1144
1
1
94
https://biotaxa.org/Zootaxa/article/view/zootaxa.1144.1.1
journal article
10.11646/zootaxa.1144.1.1
11755334
5057957
0F094220-5052-4F81-AF5F-CFBED72B1E4C
Pholetesor chiricahuensis
,
new species
(
figs. 47
,
67
)
Holotype
female
. Body length
1.7 mm
, forewing length
1.8 mm
.
Head.
Frons 1.4x broader at midheight than long down midline, finely and weakly punctate, producing dull metallic sheen between punctures; inner margins of eyes weakly converging towards clypeus. Antennae dark brown throughout, about same length as forewing; all but distal 5–6 flagellomeres with 2 ranks of placodes; flagellomere 2 3.5x longer than broad; flagellomere 14 1.2x longer than broad. Palpi moderate yellowbrown throughout. Head in dorsal view 2.1x broader than long down midline.
Mesosoma
.
Mesoscutum shallowly but distinctly punctate, becoming more indistinctly so posteriorly; surface with slight metallic sheen; width just anterior to tegulae just less than head width. Scutoscutellar scrobe straight to very weakly arched medially, composed of about a dozen sharp, regular, distinct pits. Scutellar disc mostly smoother, shinier than all but extreme posterior of mesoscutum, with widely scattered fine, shallow punctures; surface nearly flat, 1.2x longer than maximum breadth. Metanotum weakly retracted from scutellum, shallowly excavated mesad sublateral setiferous projections; transverse carinae on either side at about 1/3 of length poorly defined; sunken areas posterior to transverse carinae crossed by 3–4 short carinulae. Propodeum 2.0x broader than long at longest point, mostly very weakly rugulose, becoming shinier and smoother in posterolateral corners, with short irregular ridges radiating from nucha.
Legs.
All coxae dark brown to black virtually throughout; trochanters lighter yellowbrown; fore and midfemora very dark over basal half, gradually becoming lighter yellowbrown distally; hind femora evenly dark brown to black; all tibiae moderate yellowbrown proximally, becoming darker distally; especially so in hind tibiae; tarsi mostly deep brown. Spines on outer face of hind tibia of 2 thicknesses, approximately
20 in
number (the thinner ones difficult to distinguish at times from normal hairs). Hind tibial spurs subequal in length, slightly less than half the length of the hind basitarsi.
Wings.
Tegulae deep brown, translucent. Forewing venation deep brown, wings generally weakly tinted brownish. C+Sc+R, stigma, R1, 2r and 1Rs most strongly pigmented; R1 barely longer than stigma, about twice as long as distance from its tip to end of 3Rs fold along wing edge; 2r weakly arched, subequal with to slightly longer than 1Rs, the two meeting at a distinct 130degree angle. Hindwing with weakly arched, strongly reclivous Cu+cua; vannal lobe weakly flattened, with very short fringe (at least near midlength of lobe).
Metasoma.
Tergite I 2.4x longer than posteriorly broad, 1.5x broader anteriorly than posteriorly; lateral margins evenly curved, converging posteriorly; surface densely aciculorugose; longitudinal trend to sculpturing more obvious posteriorly; basal excavation shallowly, broadly ushaped in crosssection, reaching to about 0.3 of length of tergite. Tergite II transversesubtriangular, at least 2x broader posteriorly than anteriorly; lateral margins weakly arched; surface finely and longitudinally aciculate, the aciculations paralleling the lateral margins laterally; length about equal to posterior breadth of tergite I. Tergum III separated from II by crenulate furrow, unsculptured, slightly longer than II. Succeeding terga of usual unsculptured, unmodified, overlapping form. Laterotergites medium yellowbrown; in second tergum, laterotergite slightly darkened and sculptured near lateral margin of central tergite. Hypopygium about 1.3x longer than hind basitarsus, submedially weakly creased on either side; medial fold hairless, more flexible but not multiply creased. Ovipositor sheaths about same length as hypopygium, expanded distal hairy portions slightly shorter than hind basitarsi; sheaths narrow, fusiform, evenly hairy, very weakly decurved and more rounded dorsally than ventrally. Ovipositor weakly decurved over most of length, more strongly so near tip.
Males.
The single associated male differs from the females in the following features: antennae longer, apically more slender (flagellomere 14 2.1x as long as broad); wing venation slightly greyer; 2r and 1Rs more distinctly angled; laterotergites very dark brown; tergite I not quite so slender or posteriorly narrowed. In the shape and sculpturing of the metasomal tergites, this male is extremely similar to the female from the same locality. Body length
1.6 mm
; forewing length
1.8 mm
.
Variation.
Body length 1.6–2.0 mm, forewing length
1.8–2.2mm
. The
Arizona
specimens are noticeably smaller than the others, with somewhat straighter lateral margins to the second metasomal tergite. In the
Colorado
specimen, the second tergite is more strongly trapezoidal, longer than in the other two and with a faintly bisinuate hind margin. Despite these differences, the scattered localities and lack of host records I associate these specimens with little hesitation due to strong similarities in winbg venation, leg coloration, propodeal sculpturing and ovipositor sheath shape.
Final instar larva
. Unknown.
Cocoons.
Not recorded, but likely to be hidden within the host cocoon when attacking
Bucculatrix
, and resembling those of
P. bedelliae
when attacking
Elachista
.
Material examined.
Holotype
female:
ARIZONA
. Cochise Co., SW Research Sta.,
5 mi.
W. Portal, 5400', Chiricahua Mts.,
18VIII1978
, malaise trap 8am–6pm (M. Wasbauer).
Paratypes
:
1 male
, same data as
holotype
except
14–15VIII1978
.
CALIFORNIA
: El Dorado Co., Fallen Leaf Lake,
2 females
,
6VIII1985
(D. L. Wagner), Lot. No. 85H6, host:
Elachista
on
Elymus
.
COLORADO
. Clear Cr. Co., West Chicago Cr., 9800',
1 female
,
11VIII1961
(S.M. Clark).
FLORIDA
: Monroe Co., Key Largo, John Pennecamp St. Park,
1 male
, 14/
16XI1986
(D. L. Wagner), Lot No. 86L33, host:
Bucculatrix
on
Bourreria
.
NEW MEXICO
. Tajique.
1 female
,
VI251941
(R.H. Beamer).
Holotype
from
CDFA
collection, deposited in
USNM
;
paratypes
in
CDFA
,
CNC
(
Colorado
specimen),
Illinois
Natural History Survey
(
California and Florida
material).
Hosts.
So far two divergent hosts have been recorded,
Bucculatrix
sp. (Bucculatrigidae)
on
Bourreria
(a plant genus that in the
U. S.
appears to be restricted to
Florida
), and
Elachista
sp. (Elachistidae)
on
Elymus
(Poaceae)
. While the two hosts are quite unrelated, other species of the
bedelliae
group span these two host genera as well, so this is not particularly surprising or suspicious.
Comments.
A single specimen from the Pinaleno Mts., Graham Co., Arizona in the CAS collection may possibly be a male of this species but differs in size (it is larger), metasomal tergite shape and sculpturing, and metanotum shape from the other (
paratype
) male, which is more positively associated with the females. The reared male from Florida, although geographically disjunct, is more similar to the other Arizona material. I suspect the disjunct distribution in North America only appears so because the areas further south in
Mexico
and the Caribbean are not well sampled.
This species has the most strongly narrowing first metasomal tergite in the
bedelliae
group, and can be recognized on this feature easily, as well as by the short metacarp (R1) and subtriangular second tergite.