Revision of the willow catkin flies, genus Egle Robineau-Desvoidy (Diptera: Anthomyiidae), in Europe and neighbouring areas
Author
Michelsen, Verner
text
Zootaxa
2009
2009-03-16
2043
1
1
76
https://biotaxa.org/Zootaxa/article/view/zootaxa.2043.1.1
journal article
10.11646/zootaxa.2043.1.1
11755334
5311138
1.
Egle concomitans
(
Pandellé, 1900
)
Figs. 27
,
31–38
,
52–54
.
Anthomyia
(
Chortophila
)
concomitans
Pandellé, 1900: 251
, 287.
Chortophila cacuminata
Villeneuve, 1923: 95
. Synonymized by
Hennig (1972: 429)
.
Hylemyia hinei
Malloch, 1920b: 278
, figs. 5, 26, 33. Synonymized by Darvas (2001: 394).
Hylemyia ithacensis
Huckett, 1924: 28
, figs. 7, 63, 112. Synonymized with
Hylemyia hinei
Malloch
by
Huckett (1965: 66)
.
Chortophila concomitans
(Pandellé)
;
Séguy 1923: 123
, fig. 187.
Chortophila
(
Nudaria
)
concomitans
(Pandellé)
;
Karl 1928: 173
.
Pegohylemyia concomitans
(Pandellé)
:
Hennig 1967b: 179
, text fig. 164.
Lasiomma concomitans
(Pandellé)
;
Hennig 1972: 429
, text fig. 380, plate figs. 530, 607, 675;
Ackland & Pont 1977:
444;
Rozkošný & Barták 1984: 465
;
Fan
et al.
1988: 63
, figs. 128–130;
Hua 2006: 100
.
Egle concomitans
(Pandellé)
;
Michelsen 1988: 277
;
Barták
et al.
1989: 316
;
Barták
et al.
1990: 441
, 446; Dely- Draskovits 1993: 51;
Wei
et al.
1998: 660
, fig. 1472;
Meixnerová & Rozkošný 1999: 383
;
Teschner 1999: 131
; Darvas 2001: 394;
Darvas
et al.
2001: 309
;
Michelsen & Barták 2001: 457
;
Ackland & Merz 2003: 210
;
Griffiths 2003: 2293
, figs. 2585–2593;
Michelsen 2004
;
Hua 2006: 98
;
Komzáková 2006
.
For further references, see
Griffiths (2003)
.
Description.
Medium-sized, wing length 4.0–5.4mm.
Male.
Body covered in light greyish dusting; mesonotum in rear aspects with three broad brownish black stripes, lateral ones widely interrupted in front of suture; abdomen with mid-dorsal dark stripe and dark bands basally on tergites. Chaetotaxy of head, body and legs unremarkable, not long and dense; main setae well differentiated from setulae. Head (
Fig. 27
) much higher than long. Frons very narrow on upper part, usually less than 0.5 times diameter of anterior ocellus and with contiguous parafrontalia. Pair of interfrontal setulae in middle of frons standing immediately above series of frontal setae; orbital setulae absent. Parafacial in broadest aspect parallel-sided, narrower than postpedicel. Face with weak interantennal keel, weakly projected lower margin in profile lying slightly behind fronto-parafacial angle. Gena short, relatively broad, with setae in several irregular rows. Antennal postpedicel (
Fig. 21
) comparatively long. Proboscis short, comparatively weak; haustellum and palp both ca. 0.4 times length of fore tibia; prementum with extensive grey dusting. Proepisternals 2; proepimerals 6–8. Prealar seta about same length as posterior notopleural seta. Lower calypter nearly as big as upper calypter. Fore tibia with 0 ad-, 0 pd- and 1–3 short pv-setae; mid tibia with 1 ad-, 1 pd- and 2–3 p-setae; hind femur with a row of pv-setae interrupted basally and subapically; hind tibia with 4–6 av-setae and a more or less complete row of short pv-setae. Terminalia (
Figs. 31–38
): cerci, surstyli and gonites of distinctive shape.
Female.
Differences from male (apart from usual sexual ones): Body lighter greyish dusted, finely tinged with brown on vertex and mesonotum; pattern of dark brown striping on mesonotum very faint; grey dusting on abdomen with strong dark reflections obscuring narrow mid-dorsal dark stripe. Genal setae fewer, anteriorly in single row. Proepimerals 3–6. Fore tibia with 0–1 ad-, 0–1 pd- and 1–2 pv-setae. Mid tibia with 1–2 ad-, 1–2 pd- and 2–3 p-setae. Hind femur with only single pv-seta apically; hind tibia with 2–4 av-setae. Oviscapt (
Figs. 52–54
): Sternites VI and VII complete but narrow, each with pair of hind marginal setae; sternite VII pieces large, each with two setae at hind margin; epiproct with several setulae in addition to pair of setae; cerci rather short, broadly rounded on apical part. Three similar, moderate-sized spermathecae with cross-striae.
Material examined.
CZECH REPUBLIC
[
ZMUC
]:
Central Bohemia
:
Praha-Troja
, along river,
200m
,
7 males
28.iv.1991
,
1 male
,
2 females
16.v.1985
(
M. Barták
);
Praha-Hološovice
, river bank,
200m
,
3 males
16.v.1984
(
M. Barták
);
Lysá nad Labem
env.,
car net
,
1 male
2.v.1992
(
M. Barták
)
.
Ústi nad Labem
: Bílina-
Vĕtrák
, dump restoration,
200m
,
1 male
23–30.iv.1997
(
M. Barták
)
.
South Moravia
:
Pálava Reserve
, lowland wood,
160m
,
13 males
9.v.1997
(
M. Barták
)
.
FINLAND
[
FMNH
]:
South Karelia
:
Parikkala
,
1 male
19.v.1957
(
L. Tiensuu
)
.
SLOVAKIA
[
ZMUC
]:
Nitra
: Štúrovo-
1km
E, lowland wood,
110m
,
1 male
24.iv.1986
(
M. Barták
).
Also
seen from
CANADA
:
Quebec
and
USA
:
Alaska
,
Wisconsin
,
New York
.
Biology.
In North America, according to
Griffiths (2003)
, adults of
Egle concomitans
been found in spring on flowering willow together with other species of
Egle
, but they also regularly visit other flowers later in the season and have even been taken on moose dung and baits of liver and carrion. Unfortunately, the host plant(s) and habits of the expectedly seed-feeding larvae remains unknown. As the adults evidently interact less intimately with the host plants of their larvae than seen in other species of
Egle
, I find it most likely that larval development takes place in female catkins of poplar and aspen (
Populus
spp.
), as these are windpollinated and probably only attractive for egg-laying purposes. The pronounced continental distribution of
E. concomitans
in Europe may suggest a primary association with native species of poplar, e.g., Black poplar (
Populus nigra
L.) or White poplar (
P. alba
L.), growing preferably in flood plain forests.
Distribution.
A widespread Holarctic species reaching the northern border of Oriental Region. Apparently rare in Europe with a mainly continental and eastern occurrence, but possibly under-collected because exclusively an early-season species. Described from ‘Prusse orient.’, which refers to the present Russian enclave Kaliningrad Oblast, and from
France
(
Pandellé 1900
,
Villeneuve 1923
). Subsequently recorded from
Germany
(
Hennig 1972
),
Czech Republic
(
Rozkošný & Barták 1984
,
Barták
et al.
1989
),
Slovakia
(
Barták
et al.
1990
),
Hungary
(
Darvas
et al.
2001
),
Switzerland
(
Ackland & Merz 2003
) and
Finland
(
Michelsen 2004
). Further Palaearctic records are from
Mongolia
(D.M. Ackland
in litt.
) and
China
:
Heilongjiang
,
Liaoning
,
Beijing
,
Shanxi
and
Qinghai
(
Fan
et al.
1988
,
Wei
et al.
1998
,
Hua 2006
). Reaching the Oriental Region in northern
Myanmar
:
Kachin
(
Ackland & Pont 1977
;
Griffiths 2003
). Widespread in boreal and floodplain forests of northern North America (
Griffiths 2003
).
FIGURES 27–30.
Egle
spp.
, male head.
27.
E. concomitans
.
28.
E. ciliata
.
29.
E. brevicornis
.
30.
E. anderssoni
. Same scale.
FIGURES 31–38.
Egle concomitans
, male terminalia.
31, 32.
Sternite V, ventral and lateral views.
33, 34.
Hypopygium, caudal and lateral views.
35.
Pre- and postgonites, lateral view.
36.
Postgonite, broadest view.
37, 38.
Phallus, lateral and lateroventral views. Same scale.
Relationships.
The short and deep head profile and short proboscis (
Fig. 27
) make
Egle concomitans
very different from other species of
Egle
. Still, the detailed agreement in structural details of the male terminalia suggests that it is more closely related to the
E. longirostris
species group than to the remaining species of
Egle
. This implies that a slender and extended proboscis has been attained through homoplasy in the
E. longirostris
group and in the remaining species of
Egle
. The extended but very shallow pregonite with two strong setae found in
E. concomitans
is strikingly different from the large, bilobed and abundantly setated postgonite found in the three described species of the
E. longirostris
group. Both conditions appear apomorphic in
Egle
, but two undescribed species of the
Egle concomitans
section from
Pakistan
(D.M. Ackland,
in litt.
) combine a more plesiomorphic
type
of pregonite with a somewhat extended and slender proboscis. I assume they are phylogenetically closer to the
Egle longirostris
species group than to
E. concomitans
.