Revision of the European species of Euplectrus Westwood (Hymenoptera, Eulophidae), with a key to European species of Euplectrini
Author
Hansson, Christer
Museum of Biology (Entomology), Lund University, Soelvegatan 37, SE- 223 62 Lund, Sweden; Scientific Associate, Natural History Museum, Cromwell Road, London SW 7 5 BD, United Kingdom
christerdennis@gmail.com
Author
Schmidt, Stefan
https://orcid.org/0000-0001-5751-8706
SNSB - Zoologische Staatssammlung Muenchen, Munich, Germany
text
Journal of Hymenoptera Research
2018
2018-12-31
67
1
35
http://dx.doi.org/10.3897/jhr.67.28810
journal article
http://dx.doi.org/10.3897/jhr.67.28810
1314-2607-67-1
16E7395B44CF4B9195E3113155ECE28B
FFE2635BAD645066B306D50EEA27FFB0
2533533
Euplectrus bicolor (Swederus)
Figures
1-2
, 7-12
, 48
, 55
Pteromalus
bicolor
Swederus, 1795:204. Neotype female,
designated here
, in MZLU. Combined to
Eulophus
by
Walker (1839
:173), and to
Euplectrus
by
Haliday (1844
:297).
Elachertus albiventris
Spinola, 1811:151. Combined to
Eulophus
by
Haliday (1842
:plate J) and to
Euplectrus
by
Walker (1872b
:112); synonymized with
E. bicolor
by
Boucek
and Askew (1968
:15).
Material.
Type material:
Neotype
female labelled "
Sweden
:
Skane
,
Kranke
,
Ekskogen
,
55°41'10.3N
,
13°27'40.2E
,
5.vii.2015
,
C. Hansson
", "BC- ZSM-HYM-25460-C11" in MZLU
. Additional material (
440♀
306♂
):
Finland
:
13♀
8♂
(VV)
,
163♀
125♂
(MZH, MZLU)
, this material includes
1♀
1♂
from
Eugraphe subrosea
,
1♀
4♂
from
Agrotis
sp.,
4♀
14♂
from
Orthosia opima
,
1♀
from
Xylina
sp.,
4♀
2♂
from a "polyphagous noctuid";
France
:
18♀
4♂
(NHM)
;
Greece
:
1♀
(MZLU)
;
Hungary
:
1♂
(MZLU)
;
Norway
:
1♀
1♂
(VV)
;
Slovenia
6♂
(MZLU)
, this material includes
6♂
from
Orthosia
sp. on raspberries (
Rubus idaeus
);
Sweden
:
179♀
211♂
(MZLU, NHM, ZSM)
;
United Kingdom
:
65♀
54♂
(NHM)
, this material includes
6♀
from
Diarsia mendica
,
7♀
14♂
from
Mamestra brassicae
,
9♀
26♂
from
Polia hepatica
,
14♀
8♂
from
Polia nebulosa
. Detailed geographic information of all barcoded specimens is listed in Suppl. material S1.
Diagnosis.
Frons below level of toruli with pale area not extending laterally to the eye but with a dark stripe between pale area and eye, in the female dark area is wider (Figs
9
,
10
) than in the male (Figs
11
,
12
); midline on midlobe of mesoscutum usually indicated by either a median carina (Fig.
48
) or a median groove in posterior
1/2
, in some specimens midline indicated just through a change in the reticulation; posterior part of midlobe mesoscutum narrow (Figs
48
,
55
), ratio width base of midlobe (a)/width base of one sidelobe (b) = 0.57
+/-
0.070 (female), 0.55
+/-
0.070 (male), width base of midlobe/width base of entire mesoscutum = 0.22
+/-
0.019 (female), 0.21
+/-
0.019 (male), n= 10 for female and male respectively.
Description (neotype).
Length of body 2.8 mm (2.0-3.1 mm in additional material). Antenna with scape yellowish-brown with dorsal edge pale brown, pedicel and flagellomeres 1+2 yellowish-brown, flagellomeres 3-6 pale brown. Mandibles and palpi yellowish-brown. Head black and shiny, lower face with median part yellowish-brown reaching laterally to level of outer edge of toruli (Figs
9
,
10
). Frons smooth except a reticulate band closer to anterior ocellus than to toruli, reaching from eye to eye, close to eyes with two rows of setae (Fig.
9
). Vertex smooth and shiny. Occipital margin with a carina behind ocellar triangle.
Mesosoma black and shiny; midlobe with raised and strong reticulation, meshes isodiametric, midline on midlobe of mesoscutum usually indicated by either a median carina (Fig.
48
) or a median groove in posterior
1/2
, in some specimens midline indicated just through a change in the reticulation. Scutellum 0.9
x
as long as wide; with engraved reticulation, meshes elongate, except smooth and shiny posterior margin (Fig.
48
). Dorsellum with a very narrow groove along anterior margin (Fig.
48
), groove medially 0.1
x
as long as length of dorsellum. Propodeum smooth and shiny medially, with very weak reticulation laterally (Fig.
48
); anteromedially with strongly raised triangular cup in posterior part; propodeal callus with 17 setae. Legs yellowish-brown. Forewing: costal cell with two rows of setae on ventral surface, and margin with four setae close to marginal vein; with 17 admarginal setae.
Gaster
dark brown with a yellowish-brown spot in anteromedian part (Fig.
8
).
Ratios. HE/MS/WM = 1.8/1.0/1.1; POL/OOL/POO = 9.7/5.3/1.0; OOL/DO = 1.5; WE/WF/WH/HH = 1.0/3.0/5.3/3.6; WH/WT = 1.0; PM/ST = 1.6; TS1/TS2/LT/LT1/LT2/LT3/LT4 = 3.6/2.3/2.3/1.3/1.0/1.8; LP/WP = 0.8; MM/LG = 0.9.
Male. Length of body 1.7-2.4 mm. Scape slightly enlarged, widest medially, with sensory pores along entire ventral margin. Similar to female except wider pale clypeal area (Figs
11
,
12
), wider scape, longer petiole.
Ratios. LC/WS = 3.1-3.4, LP/WP = 1.0-1.2.
Hosts.
Agrotis
sp.,
Diarsia mendica
(Fabricius),
Eugraphe subrosea
(Stephens),
Mamestra brassicae
(L.),
Orthosia opima
(
Huebner
),
Orthosia
sp. on raspberries (
Rubus idaeus
),
Polia hepatica
(Clerck),
Polia nebulosa
(Hufnagel),
Xylina
sp., a "polyphagous noctuid". All records are from caterpillars of the
Noctuidae
.
Distribution.
Sweden (
Swederus 1795
), Finland, France, Greece, Hungary, Norway, Slovenia, United Kingdom (new/confirmed records).
Remarks.
Neotype designation: the original type material for
E. bicolor
is lost (
Graham 1963
). Presumably it was originally in the Natural History Museum in Stockholm (Sweden), but cannot be found there. When Swederus described
E. bicolor
he was very parsimonious with information, which was as usual at that time. The description is very short and fits any European species of
Euplectrus
. Biological and geographical information were not included. Swederus was working in Sweden but made scientific trips to several European countries (
Waldeck 2018
) and it is difficult to be sure from where he had the material forming the base for the description. However, since Swederus was Swedish it is probable that he had access to Swedish material. Therefore, the neotype is selected from Swedish material, and it is selected from material belonging to the species that appears to be the most common in this country. The neotype has a DNA barcode of 621 bp and belongs to one of the two haplotypes that were found within the species (Fig.
63
).
Genetic data.
Genetically analysed specimens of
E. bicolor
exhibited comparatively high levels of intraspecific variation (maximum 6.5%) but with a distinct gap to the nearest neighbours (
E. intactus
, 10.9% and
E. carinifer
, 10.2%) (Fig.
63
). The analysed specimens, all from Sweden, fall into two genetic clusters that occur sympatrically (Suppl. material S2). The absence of morphological characters to separate the two haplotypes does not preclude the possibility that
E. bicolor
consists of two or more species, but analysis of material of other populations and ideally additional (nuclear) gene regions will be required to clarify the status of each population.