Review of Mycetobia Meigen, 1818 (Diptera, Anisopodidae) in the Eocene ambers
Author
Wojtoń, Maciej
Author
Kania, Iwona
Author
Krzemiński, Wiesław
text
Zootaxa
2019
2019-01-10
4544
1
1
40
journal article
27687
10.11646/zootaxa.4544.1.1
68749531-5011-4ec9-93e5-f48416d0843f
1175-5326
2618075
BE4670E8-0A88-4838-84BC-F4AB6E2F797B
Mycetobia silvia
sp. nov.
(
Figs 19–23
)
urn:lsid:zoobank.org:act:
73DF6194-7EC9-4028-8C2D-F1321A5A188C
Diagnosis.
Flagellomeres cylindrical, becoming narrowed and more elongated to the apex of antenna, flagellomeres 1–3 as long as wide, 4–7 more than
1x
to 1.5x as long as wide, 8–13 elongated
2x
as long as wide or longer, the last one
3x
as long as wide, tapered at apex, last palpomere elongated,
8x
as long as wide, tapered at apex, longer than second one; Sc ending behind Rs bifurcation level; the distance between R
1
and R
2+3
apices approximately
5x
as long as the distance between Sc and R
1
apices; R
1
apex beyond M
1+2
bifurcation level; R
2+3
2.5x as long as Rs; M
1
and M
2
narrowly bifurcated, M
1+2
distinctly shorter than M
1
; the distance between M
1
and M
2
apices approximately one and half the distance between R
4+5
and M
1
; the distance between M
1
and M
2
apices shorter than the distance between M
2
and M
3+4;
R
2+3
and R
1
ending behind bifurcation of M
1+2
level, R
2+3
ending before half R
4+5
level; only prescutellar and apical scutellar setae thick and very elongated.
Etymology.
The species name is dedicated to Sylwia Wojtoń, wife of Maciej Wojtoń.
Type material:
Holotype
:
No. 1345(a) (sex unknown), Baltic amber, (coll. Scheele);
Paratype
:
No. 1345(b) (female), Baltic amber, (coll. Scheele).
Remarks:
two specimens are preserved in one piece of amber.
Description.
Body (
Fig. 20A
)
4.85–4.90 mm
long, dark brown with pale brown basal part of tibia and all segments of tarsus of all legs
4.84–5.03 mm
long. Head width
0.77–0.87 mm
,
0.69–0.84 mm
high. Head and thorax combined 2.12 mm–
2.20 mm
. Eyes occupying most of head in lateral view, in frontal view eyes separated by a distance about equal to diameter of ocellus; raised ocelli present and form equilateral triangle (
Fig. 21A
). Antenna
1.72 mm
long (
Figs 19A
;
21
A–E) with 14 cylindrical flagellomeres, more or less elongated, scape and pedicel comparatively short and wide; all flagellomeres with comparatively elongated and thick setae, but setae much shorter than segments bearing them and rather sparse; additionally short setae on all flagellomeres, tapered at apex last flagellomere with a few not very elongated setae at apex, last segment of antenna longer than penultimate one; palpus maxillaris 4-segmented (
Figs 19B
;
21F, G
)
0.35–0.36 mm
long, second palpomere
0.14 mm
, third
0.08 mm
, fourth
0.14 mm
long. palpomere comparatively elongated, second palpomeres cylindrical, third palpomere widened,
2x
as long as wide; third palpomere not very elongated; last one elongated and tapered at apex, longer than penultimate one; not numerous and short setae on all palpomeres.
Thorax (
Figs 20A, B
): prescutellar setae and apical scutellar setae very elongated; acrostichal setulae not very elongated; wing (
Figs 19D
;
20A
;
22
A–D): 4.00 mm–
4.20 mm
long,
1.69 mm
wide; Sc comparatively elongated, slightly arched; Rs very short,
0.34 mm
long, vein R
2+3
short,
0.98 mm
, twice as long as Rs; R
1
apex before midlength of R
4+5
level; R
4+5
arched; M
1
and M
2
approximately twice the length of M
1+2
, A
1
well developed, connected with wind edge; Halter not very elongated with elongated stem and widened knob. Legs (
Figs 19C, E
;
23
A–F): coxa of fore, middle and hind coxa with elongated bristles; coxa, trochanter and femur of all legs dark brawn, fore tibia pale brown with darkened dorsal edge, middle and hind tibia darkened in distal part; tarsus of all legs with first tarsomere pale brown, distal part of second and third tarsomere darkened, fourth and last segment of tarsus dark brown; fore, middle and hind tibia with two unequal tibial spurs; tarsus comparatively elongated with last segment only slightly longer than penultimate one and not very elongated, rather slender claw and almost invisible empodium. Apical comb well visible on fore and hind legs. Tibial spurs of fore legs unequal
0.09 mm
and
0.11mm
long, middle equal
0.12 mm
, hind
0.12 mm
long. Fore leg
4.74–4.88 mm
long, middle leg
4.96–5.34 mm
long, hind legs
5.18–5.76 mm
long. Fore coxa
0.84–0.89 mm
long, trochanter
0.20–0.21 mm
, femur
1.13–1.17 mm
, tibia
1.04–1.10 mm
, tarsus
1.50–1.51 mm
long (0.69–0.77/0.22–0.26/0.21/0.14–0.15/0.17). Middle coxa
0.78–0.93 mm
long, trochanter
0.18–0.22 mm
long, femur
1.05–1.20 mm
long, tibia
1.23–1.27 mm
, tarsus
1.72 mm
(0.86/0.27/0.28/0.18/0.18). The length of hind coxa
0.67–0.71 mm
, trochanter
0.17 mm
, femur
1.19–1.49 mm
, tibia
1.27–1.51 mm
, tarsus
1.88 mm
(0.87/0.30/0.23/0.18/0.20).
Comparison.
In contrast to other species of
Mycetobia
from Eocene, in
M. silvia
sp. nov.
flagellomeres 8–13 are elongated,
2x
as long as wide or longer. Moreover, in
M. silvia
sp. nov.
R
1
apex is positioned beyond M
1+2
bifurcation level and Sc ending beyond Rs bifurcation level, while in other species R
1
apex is positioned before M
1+2
bifurcation level and Sc ending before or opposite Rs bifurcation level, like in
M. szwedoi
sp. nov.