Eupelmus Karschii Lindeman, 1887: 187–188, Lindeman, 1887

Fusu, Lucian, 2017, An integrative taxonomic study of European Eupelmus (Macroneura) (Hymenoptera: Chalcidoidea: Eupelmidae), with a molecular and cytogenetic analysis of Eupelmus (Macroneura) vesicularis: several species hiding under one name for 240 years, Zoological Journal of the Linnean Society 181 (3), pp. 519-603 : 543-555

? Eupelmus Karschii Lindeman, 1887: 187–188 .

Syntypes ♀ ♂, ZMMU?, not examined. Type locality: Russia, Moscow. – Ruschka, 1921: 302 (synonym of E. vesicularis ). – Gahan, 1933: 51–52 (name removed from synonymy with E. vesicularis ).

Eupelmella falcata Nikol’skaya, 1952: 493. Syntypes ♀, ZIN and CNC, examined. Type locality: European part of URSS [according to label data Russia: Orenburg Oblast, Orsk] and Soviet Central Asia [according to label data Uzbekistan: Aman-Kutan] .

Macroneura falcata – Bouček, 1965: 9.

Macroneura (Macroneura) falcata – Kalina, 1981: 99.

Eupelmus (Macroneura) falcatus – Askew & Nieves-Aldrey, 2000: 57.

Description: Female. Length = 1.4–3.0 mm. Body almost uniformly dark brown, with comparatively strong, green metallic luster ( Fig. 39 ). Head brownish-black with bluish - green to golden-green lusters; vertex and parascrobal area with coppery or bronze and golden metallic luster, lower face and gena more or less extensively with bronze to coppery-red metallic luster, interantennal area frequently violet or coppery, and scrobal depression sometimes golden-green; frons usually more or less distinctly tricoloured with bluish - green to golden-green luster along inner orbits and mesally golden, bronze, or coppery to dark violet below level of anterior ocellus. Antenna with scape yellow to orangish-yellow with faint metallic luster on outer surface, pedicel and flagellum dark brown with green luster on pedicel and variably distinct bronze to violet lusters on basal funiculars. Mesosoma similar in colour to head but less metallic, mostly dark brown with dark greenish, and coppery and bronze lusters; mesoscutal plate evenly and comparatively densely setose except narrowly asetose anteriorly and posteriorly, uniformly brown, with reduced greenish metallic luster under some angles of light; axillae and scutellum uniformly brown to dark brown with multicoloured metallic lusters; scutellar-axillar complex with comparatively dense, lanceolate, reflective white setae, except setae darker anteriorly ( Fig. 92 ). Legs as described for E. balcanicus . Metasoma with dense reflective white setae, on Gt2–Gt4 distance between sockets of two adjacent setae shorter than seta length or setae slightly sparser (specimens from S France); dark brown except Gt1 translucent in distal half with the underlying yellowish-white internal structures visible to variable extent and dark basally with strong greenish-blue with coppery luster to golden-green metallic luster; Gt2 sometimes also extensively metallic dorsally. Ovipositor sheaths nearly uniformly dark brown, except some specimens with a variably developed paler elongate spot dorsally in basal half.

Head in lateral view hemispherical, 1.5–1.7× as high as long, transverse in dorsal view, 1.7–1.9× as broad as long. Frontovertex coriaceous-imbricate to reticulate. Pedicel plus flagellum 1.3–1.4× head width. Pronotal ridge rounded and inconspicuous laterally, with recumbent and undifferentiated, dark setae. Mesoscutal plate shallowly concave, reticulate anteriorly, posterior depressed region very finely coriaceous to smooth mesally and declined to median. Axillae and especially scutellum within about anterior third Λ- like angulate ( Fig. 92 ). Fore wing base extended only to about apex of scutellum ( Fig. 59 ); basal cell asetose; apical part normally abruptly bent upward, very long, 4.1–4.2× as long as basal part, with marginal and postmarginal veins extended along slightly concave leading margin and with a short stigmal vein with undifferentiated stigma; posterior margin slightly convex and leading and posterior margins curved to acute point resulting in a long-falcate fore wing apex ( Fig. 39 ). Hind wing concealed beneath fore wing and apically reflexed. Middle leg with row of only three or four mesotibial apical pegs; mesotarsus without pegs, although basitarsus with median row of one to three long seta-like spines somewhat closer to anterior margin ( Fig. 85 ). Metasoma ovoidal, 2.0–2.2× as long as wide, Gt5 alutaceous-granular. Posteroventral margins of syntergum obliquely angled inward between anal plate and ovipositor sheaths so in posterior view appearing depressed over sheath. Gaster extending over basal half of third valvula, hence ovipositor appearing very short ( Fig. 39 ). Ovipositor sheaths 0.4–0.5× as long as metatibia and 0.3× as long as metasoma.

Male. Length = 1.2–2.2 mm. Body metallic bright bluish-green ( Fig. 40 ). Head bluish-green, frequently with bronze or coppery reflections mainly in front of ocellar triangle and on scrobal depression. Lower gena with one long seta. Maxillary palpus completely yellow with last palpomere variably extensively brown or rarely completely brown. Antenna with scape dark brown with faint dark green luster except yellow in about basal third to one-fifth (yellow colour more extensive on inner surface), and on outer surface ventrally along longitudinal sensory region ( Fig. 103 ), pedicel and flagellum brown; pedicel with line of four hooked setae ventrally; fl2–fl8 with dense, semierect, slightly curved pale setae, with at most only apices of setae parallel with segment surface; fl2, fl3, and sometimes fl4 with a group of two to four short, stout, black setae ventrally. Mesosoma similar in colour to head, with bronze reflections (when present) mainly on mesoscutum and scutellar-axillar complex, and coppery-red reflections on pronotum and propodeum; notauli frequently coppery-red. Tegula bicoloured, opaque yellowish-white to yellowish-brown along inner margin and variably broadly translucent brownish apically. Fore wing translucent or with a diffuse oval infuscate area behind marginal and stigmal veins; WIP with a yellow to orange and reddish band in apical third ( Fig. 23 ). Setae of costal and basal cells, disc and venation all similarly brown to dark brown; costal cell dorsally with single line of three to five setae near leading margin over at most parastigma length, and ventrally with single row of setae along length except more setose distally in front of parastigma with setae in about 2 rows; basal cell sparsely setose, cubital fold with setal line narrowly to broadly interrupted behind speculum ( Fig. 31 ). Front leg with coxa metallic, the rest yellow except apical tarsomeres brownish, or femur with a variably extensive brownish spot medially on posterior surface, tibia variably extensively brownish ventrally, and tarsus brownish. Middle leg with coxa metallic, femur brownish, except yellowish along anterior edge and basally, to completely yellow with brownish spot medially on posterior surface, and tibia mostly yellow to yellowish-white with about apical third to one-fourth comparatively abruptly dark brown, tarsus with basitarsus whitish and following tarsomeres gradually darker, but second and third tarsomeres frequently similarly light as or only slightly darker than basitarsus. Hind leg similar to middle leg except femur yellowish ventrally and basally with the yellow colour extending variably extensively along dorsal surface, and tibia dark in about apical half to one-third, but apex of tibia light, and frequently dark markings reduced to diffuse lateral spots. Metasoma dark brown with bluish-green to coppery luster on Gt1.

Antenna ( Fig. 103 ) very long, flagellum cylindrical, clava elongate with narrow ventral micropilose sensory region, pedicel plus flagellum 1.8–1.9× head width. Fl1 inconspicuous, strongly discoidal. Basal funiculars cylindrical, fl2 2.2–2.5, fl3 2.2–2.5, and fl8 1.6–2.0× as long as wide. Funiculars with MPS in single row. Mesosoma 1.8–2.1× as long as broad. Fore wing 2.55–2.8× as long as broad. Propodeum superficially reticulate with percurrent median carina.

Comparative Diagnosis: Females of E. falcatus are easily recognized due to their characteristic very long fore wing rudiment. Specimens that have the apical part of the fore wing broken, which is sometimes common in swept material, can be recognized by the pronotal ridge without long erect setae, axillae and especially scutellum Λ- like angulate within about anterior third, mesotarsus without pegs, short wing base reaching only to the apex of the scutellum and with asetose basal cell, ovipositor sheath apparently very short and dark with at most an indistinct brownish spot.

Males of this species are easily recognized because of their metallic bright bluish-green and slender body ( Fig. 40 ), narrow fore wings with a rather conspicuous oval infuscation, largely pale palpi, scape and tegula, and mid- and hind femora and fore femur and tibia almost entirely yellow; dark markings on mid- and hind tibiae are also frequently reduced. Because of the largely pale legs, palpi and scape males are most similar to those of E. seculatus , but in this species the head has a characteristic colour (mentioned also by Pujade i Villar, 1989), with the frontovertex dark violet with some coppery reflections and the face, gena, and temples mostly bright bluish-green, the two areas of different colour being well delimited ( Fig. 38 , insert); the tegula is also brownish, the fore wing broader, the antenna shorter and the WIP has a magenta apical spot. The males of both species are also very similar to that of E. (Eupelmus) microzonus Förster ( Fig. 70 in Gibson & Fusu, 2016). The male of E. falcatus can be distinguished from that of E. microzonus because they are more slender, especially in dorsal view, with the pronotum appearing longer because the neck is not as strongly obliquely angled and the length of the lateral pronotal panel is about one-half the pronotum width. Males of E. microzonus have the neck more abruptly angled and the collar strongly transverse, with the length of the lateral panel obviously less than half the width of the pronotum. Males of E. falcatus have the dorsal setal line of the costal cell extending along the leading margin for at most the parastigma length, while in E. microzonus it extends for up to about the apical two-thirds, at least surpassing the parastigma. The male of E. seculatus is even more similar to that of E. microzonus but can be distinguished by its distinctly bicoloured head and brownish tegula.

Biology: A specialized parasitoid associated with species of Tetramesa Walker. According to Erdős (1960) also associated with species of Eurytoma Illiger parasitizing Tetramesa . I have seen specimens reared from stems of grasses with Tetramesa sp. (in Festuca sulcata ), T. aciculata (Schlechtendal) (in Stipa capillata ), T. dispar Zerova (in Stipa joannis ), from stems of Stipa parviflora ; from the galls of T. scheppigi (Schlechtendal) , T. brevicornis (Walker) , and T. schlechtendali (Hedicke) ; and from seeds of Stipa capillata and Stipa pennata with T. cylindrica (Schlechtendal) .

Distribution: Absent from Northern Europe, but otherwise distributed from Spain to Tadzhikistan ( Noyes, 2015). I have seen specimens from 12 countries of which Austria, Greece and Italy seem to be new records (see material examined). A common species in the right habitats.

Remarks: Eupelmus karschii Lindeman, 1887 was described apparently from both sexes from specimens reared from the Hessian fly. It was compared with Eupelmus allynii French ( Brasema allynii ) and differentiated because E. allynii was said to have the mesosoma triangularly uplifted [the female depicted by Riley (1885) had the mesosoma contorted]. It was probably the availability of a plate with a male of B. allynii that led Lindeman to correctly describe the males of E. ( Macroneura ) in Eupelmus , while the females were included in Euryscapus Förster ( Encyrtidae ). In the original description of E. karschii , there is one short sentence referring to the female, ‘beim Weibchen die vorderen Beine ganz gelb’ [in females fore legs entirely yellow], so Lindeman had also what he thought was a female. Ruschka (1921) rightfully considered that E. karschii was described only on males and synonymized the species with E. vesicularis , but the description of the colour of the legs does not fit the male of any species in the E. vesicularis complex. Also, the depicted antenna ( Lindeman, 1887) looks very much to that of an E. ( Macroneura ) male, but the setae are semierect and not adpressed as in E. vesicularis males. The legs of E. karschii were described as yellow, with the apices of the femora and tibiae and the last tarsal segments black. This corresponds very well with E. falcatus males, including that some specimens have the fore legs entirely yellow (possibly the female described by Lindeman), the antenna with long segments and semierect setae, and the species is associated with stems of grasses, although with Tetramesa species and not with Cecidomyiidae larvae. In E. vesicularis and E. barai , although the tibiae correspond to the description given by Lindeman, the femora are almost entirely brown. The only detail in the description that does not fit E. falcatus is the colour of the body, which was described as dark, although with green or blue metallic luster. The question of the identity of E. karschii remains open until when, and if, Lindeman’s original material becomes available.

Type material examined: Syntypes of Eupelmella f a l c a t a, 4♀: [U Z B E K I S TA N] Аман - Кутан / 5-VII 32 / Гуссаков... [ Aman-Kutan , 5 July 1932, leg. Gussakovsky] (2♀; CNC, ZIN). Same data except 13-VI 32 (1♀; CNC). [ RUSSIA, Orenburg Oblast] 9 VII 30 Орск / Artemisia , кош 5 / Чет... [9 July 1930, Orsk, Artemisia , sweeping no. 5, leg. Chet ...]; ПРЕП. 1626 [Slide no. 1626] (1♀; ZIN). All with a red label : Paratypus ♀ / Eupelmella falcata / Nik.

Non-type material: Austria (BMNH, NHMV), Bulgaria (AICF, PUPB/IBER), Croatia (BMNH, HNHM, CNC), France (BMNH, CNC, GDCO, MNHN), Greece (AICF, CNC), Hungary (AICF, CNC, HNHM), Italy (CNC), Moldova (AICF), Romania (AICF, ANCO, CNC, HNHM), and Spain (AICF). See Appendix 1.

The clade E. ( Macroneura ) s.s.

Besides the peculiar fore wing structure described above, females included in this clade have a line of erect setae on the pronotal ridge and a dorsally setose basal cell. This discriminate them from E. falcatus as in this species the setae are undifferentiated ( Fig. 59 ) and the basal cell is bare dorsally. The setae are conspicuous in light-coloured species ( Figs 56–58, 64 ) but less conspicuous in those with dark integuments ( Figs 60–63 ). Similar to the fore wing rudiment, the pronotal setae break easily ( Fig. 56 ). The scutellum is only weakly convex and not carinate anteriorly ( Fig. 95 ) as in E. falcatus and members of the clade ‘Euronmacra’.

Figures

Figures 35–42. Habitus of Eupelmus (Macroneura) species: E. aseculatus ♀ (35), E. rameli ♀ holotype (36), E. seculatus ♀ (37) and ♂ (38) with the insert showing the characteristic colour of the head, Eupelmus falcatus ♀ (39) and ♂ (40), E. barai ♀ (41) and ♂ (42). Scale bars – 1 mm.

Figures 88–95. Mesosoma in lateral view and scutellar-axillar complex in females of: Eupelmus aseculatus (88), holotype of E. rameli (89, 94), E. barai (90), E. muellneri (91), E. falcatus (92), E. impennis (93), E. vesicularis clade B (95). Scale bars – 0.2 mm for 88–91 and 50 µm for 92–95.

Figures 56–67. Mesosoma in dorsal view in Eupelmus (Macroneura) females: E. aseculatus (56), E. rameli (57), E. seculatus (58), E. falcatus (59), E. balcanicus (60), E. barai (61), E. vesicularis clade B from Canada (62), E. vesicularis from Sweden (63), E. messene (64), E. impennis (65), E. maculatus (66), E. vladimiri (67). Scale bars – 0.2 mm.

Figures 68–87. Metasoma and mesotarsus in Eupelmus (Macroneura) females: E. rameli (68, 77), E. balcanicus (69, 78), E.barai from Romania (70, 79),E. barai from Spain (71, 82), E.messene (72, 80), E.vesicularis from Sweden (73, 83),E.vesicularis from Slovenia (74), E. vesicularis clade B from Canada (75), E. seculatus (76), E. messene (lectotype of Eupelminus coleopterophagus) (81), E. impennis (84), E. falcatus (85), E. muellneri (86), E. vladimiri (87). Scale bars – 0.2 mm.

Figures 103–110. Antenna in Eupelmus (Macroneura) males: E. falcatus (103), E. seculatus with insert showing pedicel and fl1–fl4 (104), E. vesicularis with insert showing pedicel and fl1–fl3 (105), E. barai from Romania (106), E. barai from Spain (107), E. vladimiri (108), E. impennis (109), E. muellneri with insert showing pedicel, quadrate fl1 and base of fl2 (110). Scale bars – 0.2 mm. Black arrows in insert of Figures 104 and 105 point to the groups of differentiated setae on the ventral side of fl2 to fl4. White arrows in Figures 105 point to the MPS visible below the setae.

Figures 19–26. WIP on the wings of Eupelmus (Macroneura) males: E. vesicularis (19), E. impennis (20), E. barai (21), E. vladimiri – large specimen (22), E. falcatus (23), E. vladimiri – small specimen (24), E. seculatus (25), E. muellneri (26). Scale bars 0.2 mm.

Figures 27–34. Wings of Eupelmus (Macroneura) males: E. vesicularis (27), E. impennis (28), E. barai (29), E. vladimiri – large specimen (30), E. falcatus (31), E. vladimiri – small specimen (32), E. seculatus (33), E. muellneri (34). Scale bars – 0.2 mm. Arrows indicate the extent of the dorsal line of setae along leading margin of costal cell. Inserts: distal part of costal cell; dorsal setae are close to the leading wing margin, thicker, and pointing anteriorly.