﻿Review of the Palaearctic species of Miscogasteriella Girault, 1915 (Chalcidoidea, Pteromalidae)

﻿Abstract Palaearctic species of the genus Miscogasteriella Girault, 1915 are reviewed. Miscogasteriellaolgaesp. nov. from South Korea and M.vladimirisp. nov. from Japan are described. Type material of M.nigricans (Masi) and M.sulcata (Kamijo) is redescribed and illustrated. Miscogasteriellanigricans is recorded from the Palaearctic region for the first time. An identification key to females of all Palaearctic species of Miscogasteriella is given.

Unfortunately, the biology is unknown for all species of Miscogasteriella, but mostly they were collected near dead trees in forests, suggesting similar hosts to other Trigonoderinae.
The aim of this work is to describe two new species of Miscogasteriella from South Korea and Japan, and to redescribe and illustrate the species M. nigricans and M. sulcata. An identification key to females of all Palaearctic species of Miscogasteriella is also provided.

Materials and methods
The specimens examined in this study are deposited in the collections of the Deutsches Entomologisches Institut (Eberswalde, Germany; DEI), the Department of Life Sciences of the Yeungnam University (Gyeongsan, Republic of Korea; YNU), the National Institute of Biological Resources (Incheon, Republic of Korea; NIBR), the Science Museum of Natural Enemies (Geochang, Republic of Korea; SMNE), the Korea National Arboretum (Pocheon, Republic of Korea; KNA), the Entomological Laboratory of the Hokkaido University (Sapporo, Japan; EIHU), the Ehime University Museum (Matsuyama, Japan; EUM), and the Zoological Institute of the Russian Academy of Sciences (St Petersburg, Russia; ZISP).
Morphological terminology, including sculpture and wing venation, follows Bouček and Rasplus (1991), Gibson (1997), and Burks et al. (2022). The flagellum consists of two anelli, six funicular segments, and the four-segmented clava. The following abbreviations are used: POL -posterior ocellar line, the minimum distance between the posterior ocelli; OOL -ocello-ocular line, the minimum distance between a posterior ocellus and compound eye; C1-C4 -claval segments; PST -parastigma; M -marginal vein; S -stigmal vein; PM -postmarginal vein; F1-F6 -funicular segments; Mt2-Mt8 -metasomal tergites (Mt1 -petiole). The scape is measured without the radicle; the pedicel is measured in lateral view. The distance between the clypeal lower margin and the toruli is measured from the lower margins of the toruli. Eye height is measured as the maximum diameter, eye length as the minimum diameter. The mesosoma and metasoma are measured in lateral view, the latter including the ovipositor sheaths.
Specimens were examined using Olympus SZX12, Nikon SMZ745T and Zeiss SteREO Discovery V20 stereomicroscopes. Photographs were taken with a Canon EOS 70D digital camera mounted on an Olympus SZX10 microscope (ZISP specimens), and a Digital Sight PS-Fi2 camera mounted on a Nikon SMZ745T microscope (EIHU specimens). The acquired images were then processed with Helicon Focus.
Head. Head in dorsal view 2.23-2.25 times as broad as long and 1.20-1.21 times as broad as mesoscutum; in frontal view 1.26-1.29 times as broad as high. POL 0.90-0.91 times as long as OOL. Eye height 1.40-1.50 times eye length and 2.80-3.00 times as long as malar space. Distance between antennal toruli and lower margin of clypeus 0.55-0.60 times distance between antennal toruli and median ocellus. Lower margin of clypeus with angular median tooth. Antenna with scape 0.87-0.90 times as long as eye height and 1.31-1.35 times as long as eye length; pedicel 1.80-2.00 times as long as broad and 0.25-0.37 times as long as F1; combined length of pedicel and flagellum 1.67-1.70 times breadth of head; F1 3.80-4.00 times as long as broad and  (Masi, 1927), female, syntype 2, 4-8 female, non-type 1 head and mesosoma, lateral view 2 antenna 3 head, frontal view 4 head, dorsal view 5 scutellum and propodeum, dorsal view 6 metasoma, dorsal view 7 fore wing 8 habitus, lateral view. with 4-5 rows of sensilla, F3-F6 longer than broad; clava 3.07-3.40 times as long as broad, with micropilosity area on C3, and part of C2. Coloration. Head black, dorsally with metallic blue lustre. Antenna with scape, pedicel, and flagellum brown. Mesosoma metallic blue-green with diffuse coppery lustre. All coxae brown with metallic blue lustre; all femora brown; tibiae, and tarsi yellow. Fore wing hyaline, venation yellowish-brown. Metasoma with Mt2-Mt4 metallic bluegreen with diffuse coppery lustre, Mt5-Mt8 brown with diffuse violet-coppery lustre.
Head. Head in dorsal view 2.30 times as broad as long and 1.65 times as broad as mesoscutum; in frontal view 1.30 times as broad as high. POL 0.80 times as long as OOL. Eye height 1.33 times eye length and 3.10 times as long as malar space. Distance between antennal toruli and lower margin of clypeus 0.78 times distance between antennal toruli and median ocellus. Lower margin of clypeus weakly emarginate. Antenna with scape 0.68 times as long as eye height and 0.90 times as long as eye length; pedicel 1.28 times as long as broad and 0.42 times as long as F1; combined length of pedicel and flagellum 1.75 times breadth of head; F1 3.00 times as long as broad and with 3-4 rows of sensilla, F3-F6 longer than broad; clava 3.05 times as long as broad, with micropilosity area on C3 and C2. Mesosoma. Mesosoma 2.00 times as long as broad. Scutellum 1.05 times as long as broad. Propodeum without nucha and costula, 0.78 times as long as scutellum; medial longitudinal depression shallow, lateral depressions 0.44 times as long as propodeum. Fore wing 2.80 times as long as maximum width; basal cell, cubital vein, basal vein pilose; speculum absent; PST 0.55 times as long as M, M 0.53 times as long as P and 3.60 times as long as S.
Metasoma. Metasoma 6.20 times as long as broad, 2.03 times as long as mesosoma and 1.37 times as long as mesosoma and head; Mt8 1.67 times as long as broad.
Male. Body length 3.50-3.70 mm; fore wing length 2.80-3.00 mm. Head in frontal view 1.24-1.25 times as broad as high. Distance between antennal toruli and lower margin of clypeus 0.90-0.93 times distance between antennal toruli and median ocellus. Antenna with scape 0.48-0.52 times as long as eye height and 0.68-0.70 times as long as eye length. Combined length of pedicel and flagellum 1.70-1.73 times breadth of head. Antennal formula 11210. Fore wing with M 3.78-3.80 times as long as S. Metasoma 5.00-5.15 times as long as broad, 1.68-1.70 times as long as mesosoma and 1.25-1.27 times as long as mesosoma and head. Otherwise, similar to female.
Etymology. The species is named in honour of the senior author's mother, Olga Tselikh.
Sculpture. Head in frontal view weakly reticulate, in dorsal view and clypeus smooth and shiny; mesosoma reticulate, but frenum finely reticulate; dorsellum shiny, with distinct upper and lower crenulate cross-line; propodeum weakly reticulate; propodeum smooth and weakly reticulate only near medial longitudinal depression; metasoma weakly alutaceous and shiny.
Head. Head in dorsal view 2.20-2.27 times as broad as long and 1.44-1.46 times as broad as mesoscutum; in frontal view 1.29-1.40 times as broad as high. POL 0.70-0.72 times as long as OOL. Eye height 1.39-1.42 times eye length and 3.40-3.60 times as long as malar space. Distance between antennal toruli and lower margin of clypeus 0.79-0.82 times distance between antennal toruli and median ocellus. Lower margin of clypeus weakly emarginate. Antenna with scape 0.69-0.74 times as long as eye height and 0.94-1.05 times as long as eye length; pedicel 1.55-1.62 times as long as broad and 0.20-0.38 times as long as F1; combined length of pedicel and flagellum 1.53-1.78 times breadth of head; F1 3.30-4.00 times as long as broad and with 5-6 rows of sensilla, F3-F6 longer than broad; clava 2.67-2.87 times as long as broad, with micropilosity area on C3 and C2.
Mesosoma. Mesosoma 1.78-2.00 times as long as broad. Scutellum 1.07-1.10 times as long as broad. Propodeum without nucha and costula; 0.83-0.85 times as long as scutellum; medial longitudinal depression strong, lateral depressions 0.55-0.60 times as long as propodeum. Fore wing 2.80-2.89 times as long as maximum width; basal cell, cubital vein, basal vein pilose; speculum absent; PST 0.76-0.83 times as long as M, M 0.50-0.56 times as long as P and 3.00-3.35 times as long as S.
Metasoma. Metasoma 3.97-4.48 times as long as broad, 1.81-1.88 times as long as mesosoma and 1.36-1.38 times as long as mesosoma and head; Mt8 1.09-1.25 times as long as broad.
Male. Body length 3.40-6.20 mm; fore wing length 3.10-4.20 mm. All coxae dark blue; fore and middle femora yellow, hind femora brown. Eye height 1.25-1.30 times eye length and 2.70-3.00 times as long as malar space. Antennal formula 11210; scape 0.52-0.60 times as long as eye height and 0.69-0.75 times as long as eye length; pedicel as long as broad; combined length of pedicel and flagellum 2.80-3.15 times breadth of head; F1 4.80-5.00 times as long as broad. Fore wing with PST 0.61-0.69 times as long as M. Metasoma 1.00-1.28 times as long as mesosoma and head. Otherwise, similar to female.

Miscogasteriella vladimiri
Head. Head in dorsal view 2.10-2.17 times as broad as long and 1.66-1.69 times as broad as mesoscutum; in frontal view 1.30-1.34 times as broad as high. POL 0.77-0.80 times as long as OOL. Eye height 1.27-1.33 times eye length and 2.90-3.20 times as long as malar space. Distance between antennal toruli and lower margin of clypeus 0.85-0.97 times distance between antennal toruli and median ocellus. Lower margin of clypeus weakly emarginate. Antenna with scape 0.67-0.73 times as long as eye height and 0.89-0.90 times as long as eye length; pedicel 1.40-1.53 times as long as broad and 0.40-0.45 times as long as F1; combined length of pedicel and flagellum 1.56-1.57 times breadth of head; F1 2.95-3.00 times as long as broad and with 3 rows of sensilla, F3-F6 longer than broad; clava 2.30-2.50 times as long as broad, with micropilosity area on C3 and C2.
Mesosoma. Mesosoma 2.00-2.10 times as long as broad. Scutellum 1.09-1.10 times as long as broad. Propodeum without nucha and costula, 0.85-1.00 times as long as scutellum; medial longitudinal depression shallow, lateral depressions 0.30-0.35 times as long as propodeum. Fore wing 2.79-2.82 times as long as maximum width; basal cell, cubital vein, basal vein pilose; speculum absent; PST 0.62-0.67 times as long as M, M 0.55-0.60 times as long as P and 3.40-3.44 times as long as S.
Metasoma. Metasoma 4.00-4.65 times as long as broad, 1.77-1.95 times as long as mesosoma and 1.32-1.37 times as long as mesosoma and head; Mt8 1.00-1.10 times as long as broad.
Male. Body length 3.00 mm; fore wing length 2.60 mm. Eye height 1.13 times eye length and 3.40 times as long as malar space. Antennal formula 11210; scape 0.62 times as long as eye height and 0.70 times as long as eye length; pedicel 1.10 times as long as broad and 0.26 times as long as F1; combined length of pedicel and flagellum 1.78 times breadth of head; F1 4.67 times as long as broad and with 5 rows of sensilla. Mesosoma 2.00-2.10 times as long as broad. Scutellum 1.09-1.10 times as long as broad. Propodeum without nucha and transversal carina, 0.85-1.00 times as long as scutellum; medial longitudinal depression shallow, lateral depressions 0.30-035 times as long as propodeum. Fore wing 2.79-2.82 times as long as maximum width; basal cell, cubital vein, basal vein pilose; speculum absent; PST 0.62-0.67 times as long as M, M 0.55-0.60 times as long as P and 3.40-3.44 times as long as S. Metasoma 1.33 times as long as mesosoma and as long as mesosoma and head. Otherwise, similar to female.
Etymology. The species is named in honour of the senior author's father, Vladimir Tselikh.