Revision of the Myopa testacea Species-Group in the Palaearctic Region (Diptera: Conopidae)
Author
Stuke, Jens-Hermann
Author
Clements, David K.
text
Zootaxa
2008
1713
1
26
journal article
10.5281/zenodo.274119
0c4c707f-ee5e-4ec0-9bbb-2dcd8664502f
1175-5326
274119
The
Myopa testacea
Species-Group
The
testacea
-group is, together with the closely related
polystigma
-group, distinguished from all other
Myopa
species-groups by the following combination of characters: (1) conspicuous white hairs on the ventral occiput (i.e. white ‘cheek whiskers’); (2) the crossvein r-m is black, and usually lies within a conspicuous blackish wing marking; and (3) the absence of a conspicuous, dense and isolated wing marking in the centre of cell r4+5. Segregation of the
testacea
-group from the
polystigma
-group is more difficult, although this is normally possible through the more strongly spotted wings of the latter. In the
polystigma
-group there is normally blackish marking of the wing membrane along much of the length of vein M, but the marking along the outer section of this vein (M2) is usually obviously interrupted in the middle section so as to produce distinct and obviously isolated spots at the wing apex and at the junction of M2 with the outer crossvein dm-cu (
Fig. 2
). In the
testacea
-group these markings are either absent entirely (
Fig. 1
), or if present then the blackish coloration along vein M2 runs uninterrupted from the outer crossvein dm-cu to the wing apex. This distinction is sometimes unclear in
Myopa vicaria
Walker, 1849
which is currently considered to belong to the
polystigma
-group, but this species also differs from the
testacea
-group in lacking any distinct rows of setose bristles in the basal part of the undersides of tibiae 1 and 2.
Myopa vicaria
is usually also distinctive in having very long hairs on the body, the longest of which are clearly longer than the hind metatarsus, as well as in having markedly pale (i.e. yellowish-orange) abdominal coloration.
These two species-groups have been separated as a matter of expediency and probably do not form natural taxonomic groupings. Their maintenance may therefore eventually prove to be unsustainable. However, their separation is presently invoked in order to allow the early revision of the
testacea
-group.
As far as can be ascertained, all species of the
testacea
-group are univoltine and fly mainly in the spring months, although at higher altitudes and in northern areas especially, the flight period may extend until July or later. The
testacea
-group appears to be confined to the Palaearctic region.