The species of four genera of Metopiinae (Hymenoptera: Ichneumonidae) in Britain, with new host records and descriptions of four new species
Author
Broad, Gavin R.
Author
Shaw, Mark R.
text
Journal of Natural History
2005
2005-06-30
39
26
2389
2407
http://dx.doi.org/10.1080/00222930500102074
journal article
10.1080/00222930500102074
1464-5262
5215648
Stethoncus monopicida
sp. n.
Stethoncus sulcator
Aubert
;
Gauld and Sithole 2002
, p 222
, misidentification.
Female
Body length
4.4–5.4 mm
. Fore wing length
3.2–3.8 mm
. Antenna with 21–25 flagellar segments, shortened and somewhat laterally compressed, F1 averages 0.89 times as long as wide in lateral view, 1.67 times in anterior view; F2 (this and following measurements in lateral view) 0.70; middle flagellomeres 0.75; penultimate flagellomere 0.83. Scape with stout setae ventrally (
Figure 8
). Mesoscutum approximately 1.25 times as wide as long (width measured at the tegulae and the length from the mid-point of the tegula line to the anterior edge) (
Figure 9
). Mesosoma and head uniformly, regularly punctate, with rather long setae over much of the dorsum of the body. Propodeum with broadly confluent areas superomedia and basalis, the lateromedian longitudinal carinae straight except for a slight inflection at the point where the areas superomedia and basalis meet and, often, basally. The dorsal longitudinal carinae of the first metasomal tergite end at about the mid-point of the tergite. Black, but with mouthparts, upper edge of face before the antennal shelf, antennae, tegulae and legs (except hind coxae) yellowish brown. Metasoma slightly paler than mesosoma. Pterostigma mid-brown.
Male
Body length
4.8–4.9 mm
. Fore wing length
3.5 mm
. Similar to female but with antennal flagellum slenderer, not laterally compressed, with 21–27 flagellar segments, F1 averages 1.74 times as long as wide; F2 1.3; middle flagellomeres 1.55; penultimate flagellomere 1.50. The dorsal longitudinal carinae of the first metasomal tergite end at about threequarters to four-fifths of the length of the tergite.
Comments
This species is separable from
S. sulcator
Aubert
by having the pronotum postero-dorsally with more curved sides (compare
Figures 9
and
11
); the mesoscutum wider (compare
Figures 9
and
11
); the longer first segment of the female flagellum (compare
Figures 8
and
10
); and the straighter lateromedian longitudinal carinae of the area superomedia.
Stethoncus arcticus
Townes
(
one paratype male
examined, Mt McKinley, 2
°
009,
15 August 1954
(D. Townes), in AEI) has an even slenderer mesoscutum than
sulcator
and also a slenderer first tergite.
Material examined
Holotype
:
♀
, ‘‘Scotland [
UK
], DN,
Rhossdu
[
sic
] estate,
A.F.G. Dixon
B.M. 1961.101
Host
:
Monophis
[
sic
]
rusticella
Hb. Em. Ex Barn Owl
pellet
Rossdhu
June 1959
’’ (
BMNH
)
.
Paratypes
:
Scotland
: 1
„
, same data as holotype (
BMNH
)
.
England
:
1♀
,
Silwood Park
,
Ascot
,
Berks.
, 51
°
249N, 0
°
389W,
Malaise trap
in wet woodland,
30 August to 6 September 1999
(G.
R
.
Broad
) (
BMNH
)
;
1♀
,
Chippenham Fen
,
Cambs.
, TL 650693,
Malaise trap
: carr at reedbed edge,
16–24 June 1983
(
J. Field
) (
NMS
)
;
1
„
and
1♀
, as above but
9–22 July 1983
(
NMS
); 1
„
, as above but
8–21 August 1983
(
NMS
)
;
3♀♀
, as above but
15–27 August 1983
(
NMS
)
;
1♀
,
Wychwood Forest
,
Oxon.
, SP 345170,
Malaise trap
,
17 July to 14 August 1990
(
K. Porter
) (
NMS
)
;
1♀
Monks Wood
,
Hunts.
, TL 199797,
Rothamsted light trap
,
15 June 2004
(
N. Greatorex-Davies
) (
BMNH
)
.
Biology
The
holotype
female and a
paratype
male were reared from
Monopis laevigella
([Denis and Schiffermüller]) (5
rusticella
(Hübner))
(
Lepidoptera
:
Tineidae
) in Barn Owl (
Tyto alba
(Scopoli))
pellets; the host pupae are preserved with the specimens. The pellets were collected at the bottom of a chimney below a Barn Owl roost and these were the only parasitoids reared (A. F. G. Dixon, personal communication to M. G. Fitton). These are the specimens referred to as
S. sulcator
by
Gauld and Sithole (2002)
.
Etymology
This species’ name is derived from the tineid genus,
Monopis
, from which it has been reared.