The discovery of Megalota in the Neotropics, with a revision of the New World species (Lepidoptera: Tortricidae: Olethreutini)
Author
Brown, John W.
text
Zootaxa
2009
2009-11-02
2279
1
1
50
https://biotaxa.org/Zootaxa/article/view/zootaxa.2279.1.1
journal article
10.11646/zootaxa.2279.1.1
1175-5326
5307538
1.
Megalota submicans
(Walsingham)
,
new combination
Figs. 1
,
25
,
49
Episimus submicans
Walsingham, 1897: 124
;
Powell
et al
. 1995: 152
;
Brown 2005: 308
.
Diagnosis
.
Megalota submicans
can be distinguished from
M. synchysis
by the possession of a small posteriorly-projecting thorn at the distal end of the phallus; in
M. synchysis
the thorn projects more laterally and is located slightly subapically. Also, the basal process of the valva of
M. submicans
is nearly uniformly in width, whereas that of
M. synchysis
is broadest in the basal half and conspicuously narrower in the distal half. In the female genitalia of
M. submicans
, the subtriangular mesal lobe of the sterigma is oriented almost directly posterad, while in
M. synchysis
it is oriented more laterad.
Redescription
.
Head
: Vertex mixed pale brown, creamy brown, and creamy white, frons mostly creamy white; labial palpus creamy white with small patches of brown and a small patch of pale red-brown near tip of segment II.
Thorax
: Dorsum pale gray brown with some creamy white-tipped scales, posterior crest dark copper-brown. Hind tibia in male with conspicuously enlarged tuft of white scales and hairpencil. Forewing length
6.1–7.1 mm
(mean = 6.5); pattern complex, variable; basal 0.25 mostly pale brown with irregular patches of pinkish brown and creamy white, bordered distally by a curved, pinkish gray subbasal fascia with undulate edges, faintly outlined by creamy white; mesal 0.25 of wing darker with small, dark red-brown semicircular blotch from costa near middle; a small, slender, oblong brown patch from near mid-termen approaching costa ca. 0.75 from base to apex, ending bluntly before reaching costa, bordered by area of pinkish creamwhite, irregularly reticulated with orange-brown. Hindwing pale brown; anal margin in male with fold poorly defined.
Abdomen
: Dark fuscous. Short, white tuft of scales from posterior edge of the sterigma in female, one at latero-anterior end of each papilla analis (lost in slide mounted preparations). Male genitalia (
Fig. 25
;
6
preparations examined) with tegumen elongate-ovate, slightly concave laterally with small expanded lobe just before uncus; uncus broadly cordate with shallow mesal notch, densely spined; socius membranous with few bristles; valva asymmetrical, venter of left valva bent at ca. 100° angle about 0.33 distance from base with sparse patch of long setae in basal half, with setae nearly as long as valva; venter of right valva evenly curved with sparse, shorter setae (often lost in slide preparations); a broad, incurved projection from valva ca. 0.65 distance from base to apex, strongly sclerotized along one side with tiny, distally-curved setae; dense patch of long, fine setae at base of projection; basal process of the valva short, stout, ca. 3 times as long as wide, with 3-5 large spines at blunt distal end. Phallus slender, ca. 0.15 as wide as long, elongate, ca. 0.5 as long as valva, slightly curved in basal 0.3, with small external thorn near tip; vesica with two small, slender cornuti. Female genitalia (
Fig. 49
;
6
preparations examined) with papillae anales unmodified; sterigma rounded shield-shaped, with slender triangular process with rounded apex mesally posterad of ostium, directed slightly to right; colliculum occupying posterior 0.3 of ductus bursae, weakly curved at anterior end, with C-shaped opening at anterior end, anterior 0.7 of ductus bursae membranous; corpus bursae rounded-oblong, finely punctate throughout; signum a short irregular band of blunt spines of variable length from a weakly sclerotized plate.
Holotype
. Male,
West Indies
,
Grenada
, Balthazar (Windward side), [no date]
H. H. Smith
, Walsingham Collection 1910–427 (
BMNH
).
Additional Material Examined
(
13♂
,
42♀
).
WEST INDIES:
Grenada
: [no date] (
4♂
,
3♀
), W.
Schaus
(
USNM
)
.
L.
Grand Etang
,
4–6 Aug 1963
(
1♂
),
O. S. Flint
(
USNM
)
.
Dominica
:
Clarke Hall
,
3 Feb 1964
(
1♂
), D. F.
Bray
(
USNM
)
,
25 Apr 1964
(
1♀
), O. S.
Flint
,
Jr.
(
USNM
)
,
8 Jan 1965
(
1♀
),
9 Jan 1965
(
1♀
),
10 Jan 1965
(
1♀
),
12 Jan 1965
(
1♀
),
14 Jan 1965
(
1♂
),
22 Jan 1965
(
1♀
),
24 Jan 1965
(
1♀
),
5 Feb 1965
(
1♀
), all J. & T.
Clarke
(
USNM
)
,
21–31 Jan 1965
(
1♂
,
1♀
), W. W.
Wirth
,
light trap
(
USNM
)
. Grande Savane,
13 May 1964
(
3♂
,
8♀
),
20 May 1964
(
1♀
),
7 Jun 1964
(
3♀
),
1 Jul 1964
(
8♀
), all O. S.
Flint
,
Jr.
(
USNM
)
,
11 Jun 1965
(
1♂
,
2♀
), D. R.
Davis
(
USNM
)
.
Springfield Est.
,
20–26 Jul 1963
(
1♀
),
O. S. Flint
,
Jr.
(
USNM
)
.
St. Lucia
:
Cul de Sac
R. at M.P. 9,
29 Jul 1963
(
2♀
),
Flint
&
Cadet
(
USNM
)
.
Marisule
,
30 Jul 1963
(
2♀
),
O. S. Flint
,
Jr.
(
USNM
)
.
Vergallier R.
, nr
Marquis
,
31 Jul 1963
(
1♀
),
Flint
&
Cadet
(
USNM
)
.
Miguy
,
19 Nov 1975
(
1♀
), [no collector] (
USNM
)
.
1.5 mi
S Mt. Gimie
,
19–24 Nov 1975
(
1♂
), E. L.
Todd
(
USNM
)
.
Distribution and Biology
.
Megalota submicans
appears to be widely distributed in the West Indies (Caribbean), with numerous records from
Grenada
,
St. Lucia
, and
Dominica
. Adults have been collected primarily in May through August, with a few specimens from November (n = 2), January (n = 5), and February (n = 1). Nothing is known of the early stages.
Remarks
. Although
M. submicans
was described in
Episimus
and treated as such by
Powell
et al
. (1995)
and
Brown (2005)
, the forewing pattern, male secondary scaling, male genitalia, and female genitalia all provide convincing evidence that it belongs in
Megalota
.
Megalota submicans
ranges throughout much of the Caribbean, with slight morphological variation detectable among populations from different islands—
Grenada
(
type
locality),
Dominica
,
St. Lucia
–especially in the position and shape of the external thorn of the phallus. While these differences potentially represent species-level character states, they are difficult to quantify; hence, I adopt a conservative approach and treat all Caribbean members of the group as conspecific with
M. submicans
. In contrast, the
submicans
-like populations from
Venezuela
(e.g., Rancho Grande,
1100 m
) have differences in the male and female genitalia that are more easily described, and combined with the different habitat and elevation, I consider these to represent a distinct species,
M. synchysis
.
I have examined at least
ten specimens
that are extremely similar to
M. submicans
but are different enough in details of the genitalia that their assignment to that species is questionable. A single male from
Hidalgo
County, Texas (USNM) may represent
M. submicans
, but the phallus is much longer and more curved than in other specimens. A series of specimens (n = 3 USNM and 3 EME) from
Veracruz
,
Mexico
also appears to represent
M. submicans
, but males lack the distinctive angle at the ventral edge in the basal portion of the valva characteristic of
M. submicans
, and females have a weakly sclerotized, rounded disc around the post-osteal region. Extraordinarily, a single male from
Formosa
,
Argentina
(USNM) also appears to represent this species. While it is possible that the Mexican and Texas specimens are conspecific with
M. submicans
, it seems unlikely that
the Argentine
specimen is. It also is possible that each of these groups represents a distinct species, but owing to the paucity of material, they are difficult to circumscribe confidently.