Additions to the Swedish fauna of Diplazontinae (Hymenoptera: Ichneumonidae) with the descriptions of five new species
Author
Johansson, Niklas
B0031F47-99F7-4FEE-B545-B6F1E79E1A4E
Baskarp Fredriksberg 1, 566 92 Habo, Sweden.
chrysis32@yahoo.se
text
European Journal of Taxonomy
2020
2020-11-20
724
70
92
journal article
3994
10.5852/ejt.2020.724.1159
5adf46ff-aa14-4b94-9e2b-73a26f6d2fe1
2118-9773
5578733
966176C3-0297-493F-9567-1348BFB5DBFC
Homotropus hellqvisti
sp. nov.
urn:lsid:zoobank.org:act:
F3840017-E3FA-4A8A-99EC-15EB8C79310D
Figs 2
,
5C
Diagnosis
Homotropus hellqvisti
sp. nov.
(
Fig. 2
A–B) is similar to
Homotropus collinus
(Stelfox, 1941)
(
Fig. 5D, F
), but is primarily distinguished based on the irregular microsculpture on the 3–7
th
tergites (
Fig. 2B
) and the shorter and more weakly excised clypeus (
Fig. 5C
). The new species is also similar to
Homotropus melanogaster
(Holmgren, 1872)
(
Fig. 5E
) from which it differs by the only weakly laterally compressed metasoma (in
H. melanogaster
the metasoma is strongly compressed, knife-like from the 5
th
tergite onwards), the irregular microsculpture on the 3–7
th
tergites (
Fig. 2B
), the absence of a subbasal dark spot on the hind tibia and the usually more numerous flagellomeres. Note that while the females of
H. melanogaster
usually have the mid and hind coxae infuscate, the species sometimes occurs in a colour
variety with
red hind coxae in
Sweden
(
Klopfstein 2014b: 68–69
) (see Remarks). The number of flagellomeres ranges from
17–19 in
H. melanogaster
(n = 20) and
19–20 in
H. hellqvisti
sp. nov.
Two of the three known females all have distinct, quite large shoulder marks, while only one of the studied females of
H. melanogaster
(n = 17) has small and diffuse shoulder marks.
Etymology
The specific epithet
hellqvisti
(masculine name in genitive case) is derived from the name of one of the collectors of the specimens who revealed the presence of this new species, Sven Hellqvist (Umeå,
Sweden
).
Type material
Holotype
SWEDEN
•
♀
;
Västerbotten
,
Åselet
,
Hästholmen
;
65.233° N
,
20.414° E
;
25 May–19 Aug. 2019
;
R. Mugerwa Pettersson
and
S. Hellqvist
leg.;
Malaise trap in riverside, herb rich, mixed forest
;
NHRS-
HEVA000011635
.
Paratypes
SWEDEN
•
2 ♀♀
; same collection data as for holotype;
NHRS-HEVA000011636
,
NHRS- HEVA000011637
.
Description
Female
Fore wing length
4.2–4.3 mm
. Body length
5.5 mm
. Head transverse in anterior view. Inner orbits parallel. Face entirely coriaceous and matt. Clypeus with apical margin bilobed and thin, weakly excised centrally (
Fig. 5C
). Antennae with 19–20 flagellomeres. First flagellomere about four times as long as wide. Apical flagellomeres with multiporous plate sensillae also present ventrally. Head behind eyes slightly narrowed. Temple in lateral view about 0.6 times as wide as compound eye. Mesoscutum matt with fine rugulose microsculpture and very weak punctures dissolving against background. Mesopleuron in lower half irregularly rugulose, in upper half polished, below subtegular ridge with irregular punctures. Metapleuron coriaceous. Propodeum evenly coriaceous without carinae. Coxae coriaceous, matt. Fore wing with areolet closed and vein 3rs-m unpigmented (
Fig. 2A
). Metasoma laterally weakly compressed from the 4
th
tergite onwards (
Fig. 2A
), with dense hairs. First tergite stout, slightly longer than wide, evenly coriaceous with a faint indication of longitudinal striae in apical corners. Second tergite evenly coriaceous. Third tergite onwards with fine irregular microsculpture (
Fig. 2B
). Spiracle of second and third tergite above lateral fold. Ovipositor sheath apically rounded.
Fig. 2.
Homotropus hellqvisti
sp. nov.
, paratype, ♀ (NHRS-HEVA000011637).
A
. Habitus, lateral view.
B
. Posterior segments of metasoma.
COLOURATION. Body and head black. Mandibles, palpi, occasionally subtegular ridge, hind corner of pronotum and tegulae whitish. Clypeus yellowish. Pale central face patch absent or diffuse. Yellowish shoulder mark small or absent. Scutellum black. Pterostigma transparent brownish. Legs orange, fore coxae white, basally more or less black. Mid and hind coxae orange. Trochanter and trochantelli yellow except for hind trochanter, which is orange. Tibiae whitish. Fore and mid tibia with yellow apices. Hind tibia with apical 0.25 black and base very narrowly infuscate. Hind tarsi black. Mid and fore tarsi whitish, except for brownish apical segment. Metasoma black.
Male
Unknown.
Remarks
Klopfstein (2014b)
noted that some females of
Homotropus melanogaster
collected in
Sweden
had orange hind and mid coxae, thereby differing in colour from the nominate form with black coxae. Since both forms also often occurred together at the same localities, they were treated as varieties of the same species. The actual specimens with the red coxae studied by Klopfstein bear a handwritten label “sp. X”. I have studied
5 ♀♀
and 2 ³³ of this form of
H. melanogaster
(NHRS, SMTP)
and it is not conspecific with the species here described and apart from the paler coxae there are no reliable distinguishing characters between the two forms. In the key to the species of
Homotropus
Förster, 1869
provided by
Klopfstein (2014b)
,
Homotropus hellqvisti
sp. nov.
will run to either couplet 6 together with
Homotropus melanogaster
or to couplet 8 with
H. collinus
. For distinguishing characters, see Diagnosis.
Ecology
The three known females were collected by a Malaise trap situated in a herb rich riverside boreal forest dominated by birch
Betula
spp. along the forest river Byskeälven The area (
Fig. 12
A–B) rests on sandy ground and is periodically flooded. The trap also collected several rarely recorded diplazontines such as
Syrphoctonus idari
Diller, 1985
,
Homotropus melanogaster
,
Diplazon neoalpinus
Zwakhals, 1979
and
Syrphophilus asperatus
Dasch, 1964
.