Description of the pupal exuviae of some species belonging to Orthocladius s. str. van der Wulp, 1874 (Diptera: Chironomidae: Orthocladiinae), with a new key to species of West Palaearctic region
Author
Bruno Rossaro
Author
Carlotta Casalegno
text
Zootaxa
2001
2001-08-31
7
1
20
journal article
http://doi.org/10.5281/zenodo.4618447
b8a70227-3f95-4b6c-bab0-423990ebbee0
11755326
4618447
B8D6DBE1-9599-4328-A653-6B10532F5C48
Orthocladius ticinoi
Rossaro
&
Prato,
1991
O
. ticinoi
Rossaro
&
Prato,
1991
Orthocladius
Pe
7
Langton,
1984
:
155
(
Langton
1991
:
190
a tentative synonym)
nec
O
. glabripennis
Goetghebuer,
1921
, sensu
Rossaro
1991
DESCRIPTION. See
Rossaro
&
Prato (
1991
, Fig.
17, 18
)
. Colour pale transparent. Frontal warts not developed. Thoracic horn slender at apex,
240420 m
long, with points less developed than in
O
. obumbratus
. Thorax moderately rough. Pedes spurii B developed. On T
II
only posterior point field present.
TIII
with posterior points not extended laterally beyond apical points. Points on
TIIIVI
limited to a central trapezoidal area; there is a sudden drop in point size to anterolateral points. Posterior points on
TIIIVI
and apical points on
TIIIV
more developed than the anterior ones, onT
IV
VI
anterior points more developed than the median ones.
SIIIV
with more or less extended fields of very small grouped points. Pedes spurii A present on S
IVVII
. Lateral setae:
1
on segment
I
,
3
on segments
IIVI
,
4
on segment
VII
and
5
on segment
VIII
. Anal lobes with small colourless apical taeniate extensions of cuticle, at most
30 m
long, with the shape of small colourless teeth (Fig. 2.3), laterally in addition very small apical extensions may be present. Anal macrosetae
225265 m
long, anal lobes
325420 m
long,
350490 m
wide.
COMMENTS. The species can be easily separated from
O
. obumbratus
,
in which well sclerotized extensions of cuticle at the tips of anal lobes, resembling spurs, are observed.
Rossaro (
1991
)
synonymized
O
. ticinoi
with
O
. glabripennis
(=
Orthocladius
Pe
5
), because of the presence of small and colourless teeth (
Langton
&
Cranston
1991
), but apical taeniate extensions of cuticle apparently are always absent in
O
. glabripennis
and there is no variation within the species in this respect,
O
. glabripennis
is a lentic species,
O
. ticinoi
is restricted to running waters besides this. The conclusion is that specimens with small colourless apical taeniate extensions of cuticle do not belong to
O
. glabripennis
, but to
O
. ticinoi
, which is a separated species. According to
Langton (
1991
)
description,
O
. ticinoi
be identical with
Orthocladius
Pe
7
Langton
1984
:
155
.
MATERIAL EXAMINED:
FRANCE
: GARONNE river,
10
/
3
/
1997
, 1 Pex.
ITALY
: LOMBARDIA: Brembo river,
26
/
2
/
2001
, 1 Pex; Serio river, Ricengo,
18
/
2
/
2001
, 1 Pex;
23
/
3
/
2000
, 1 Pex; Ticino river, Oleggio,
16
/
2
/
1995
, 1 Pex; Boffalora,
11
/
1
/
1981
, 1 Pex,
25
/
1
/
1981
, 1 Pex,
1
/
5
/
1981
, 1 Pex,
11
/
2
/
1993
, 1 Pex; Castelletto,
14
/
2
/
2001
, 9 Pex;
5
/
3
/
2001
, 1 Pex. EMILIA ROMAGNA: Po river, Caorso,
12
/
4
/
1977
, 1 Pex;
13
/
12
/
1983
, 1 Pex; Chiavenna stream, tributary of Po river,
10
/
4
/
1979
, 1 Pex. ABRUZZO: Aterno river, Coppito,
28
/
2
/
1992
, 1 Pex.