See van Achterberg (1991: 19). The type species of Lysitermus Foerster was not described in 1863; the species name is valid because it was the only species included in the new genus. Indirectly, the type species is characterised by the two features mentioned in the key to the genera (vein 2-SR of fore wing absent and only three metasomal segments visible) but its unequivocal recognition has been problematical. Therefore, we illustrate here recently reared specimens from Sweden, because the cotypes of L. pallidus in ZMB are less suitable for redescription and in any case not currently available.

Figure 1. 

Lysitermus pallidus Foerster, ♀, Sweden, habitus lateral. Photograph: R. Soethof.

Facultative gregarious parasitoids of case-bearing lepidopterous larvae of Psychidae and Tineidae; they are almost certainly idiobiont ectoparasitoids (Gupta and Quicke 2018; Mifsud et al. 2019; this paper). There is no mummification of the host larva, as in Rogadinae, and the host remains in the host case are compatible with ectoparasitoism (M.R. Shaw pers. comm.). The records of Scolytini (Pityophthorus micrographus (Linnaeus, 1758), Polygraphus poligraphus (Linnaeus, 1758)) are based on a mass rearing from a dead Picea abies tree infested by both species (Hedqvist 1957). As Lysitermus has been reared from case-bearing larvae so far and there is no direct rearing known from Curculionidae (Scolytini), we consider both records very doubtful.

Lysitermus Foerster and the widespread Old World genus Acanthormius Ashmead, 1906, are very similar and should be synonymised in future if molecular data show that Acanthormius and Lysitermus are paraphyletic. Up to now, with only few species sampled, the Old World Lysitermus species sampled clusters with Afrotritermus Belokobylskij, 1995 and Atritermus Belokobylskij, Zaldivar-Riverón & Quicke, 2007 and not with the Acanthormius clade (Jasso-Martínez et al. 2021). Therefore, we refrain from synonymising both genera, despite that both have vein CU1a of the fore wing at the level of vein 2-CU1 or above (Fig. 2) and lack a parastigma (but the parastigma is also rarely absent in Aulosaphoides van Achterberg, 1995). However, in Acanthormius vein 2-SR of the fore wing is complete and the third tergite, excluding lamella, usually protruding latero-apically. In Lysitermus vein 2-SR is often largely or entirely absent, if present then nearly always its posterior third unpigmented and only the lamella of the third tergite is protruding. The development of vein 2-SR is very variable; the specimen in Figure 2 has the vein in one wing only pigmented, as figured, but in the other wing entirely sclerotised. In Aulosaphoides vein CU1a of the fore wing is situated distinctly below the level of vein 2-CU1 (at the same level or above in Lysitermus) and vein r is emitted distinctly before the middle of the pterostigma (submedially in Lysitermus). Trissarthrum Ashmead, 1900, is traditionally included in Lysitermus (Wharton 1993; van Achterberg 1995; Yu et al. 2016), but its Neotropical type species, T. maculipennis Ashmead, 1900, from St. Vincent has a complete vein 2-SR of the fore wing and the propodeal areola comparatively narrow. Therefore, it may be a different Neotropical genus near Acanthormius lacking the apico-lateral protruding part of the third tergite and having vein M+CU1 of the fore wing non-tubular and vein 1-M of hind wing much longer than vein M+CU (van Achterberg 1995). Both characters are also present in the only other described species from the New World, L. woolleyi Wharton, 1993 from Mexico. The Australian Lysitermus sp. 1 listed by Jasso-Martínez et al. (2021) clusters with the Afrotropical genera Afrotritermus Belokobylskij, 1995 and Atritermus Belokobylskij, Zaldívar-Riverón & Quicke, 2007. The listed Neotropical Lysitermus sp. 2 (= Trissarthrum) clusters with the Acanthormius clade (Jasso-Martínez et al. 2021). Lysitermus without Trissarthrum has an Old World distribution, known from the Afrotropical (Papp and van Achterberg 1999; van Achterberg 2000), Australian (Jasso-Martínez et al. 2021), and Palaearctic regions (Yu et al. 2016).

Figures 2–8. 

Lysitermus pallidus Foerster, ♀, Sweden 2 wings 3 mesosoma dorsal 4 metasoma dorsal 5 second and third metasomal tergites dorsal 6 head anterior 7 head dorsal 8 detail vertex dorsal. Photographs: R. Soethof.

The position of the tribe Lysitermini is uncertain, but there is increasing evidence for a subordinate position in the Hormiinae. Recently, Lysitermini are either included as a tribe in the Rogadinae sensu lato (Chen and van Achterberg 2019) or the Hormiinae (Jasso-Martínez et al. 2021), or treated as a separate subfamily (Quicke et al. 2020).

Figures 9–11. 

Lysitermus pallidus Foerster, ♂, Sweden 9 habitus lateral 10 third metasomal tergite dorsal 11 propodeum and metasoma dorsal. Photographs: R. Soethof.

5 ♀ + 1 ♂ (= type series of L. pallidus; ZMB), “[Germany], Aachen”, “Frst”, “pallidus Furst”, “Fam. 3 Hecaboloidae, n. gen. (rest illegible)”; 4 ♀ + 1 ♂ (RMNH), “Sweden: Skåne, Fjälkestad, Balsberget, ex cases of Diplodoma laichartingella (Goeze) (Psychidae), coll. 25.vi.2019, em. (indoors) 18.ii.2020, F. Skeppstedt”; 1 ♀ (NMS), “Finland: Lemland, Flaka, Björkö, 59.98°N, 20.19°E AI, 3.viii.2004, ex ?Psychid [= Diplodoma laichartingella] case, N. R. Fritzen”, “♀ Ant 17, Lysitermus pallidus Foerster, det. M. R. Shaw 2015”.

Figured and reared ♀ from Sweden (RMNH), length of body 2.2 mm, and of fore wing 1.6 mm.

Head. Antenna 1.2× as long as fore wing, with 16 segments, slightly widened apically (Fig. 1), scapus oblique apically, length of third segment 1.3× fourth segment; third, fourth and penultimate segments 5.0, 4.0, and 2.4× their width, respectively; face largely smooth, with long erect setae and 1.7× wider than high; clypeus smooth, upper half distinctly convex and ventral half depressed; head in dorsal view 1.8× broader than long medially, eye 1.3× longer than temple dorsally, strongly and roundly narrowed posteriorly (Fig. 7); vertex finely granulate and superficially rugulose near stemmaticum (Fig. 8); occipital carina strong and in front of it crenulate; POL: diameter of posterior ocellus: OOL = 4:2:6; eye in lateral view 1.6 × as high as wide, temple distinctly broadening ventrally and width of eye 1.2× minimum width of temple (Fig. 1); malar space 0.7× as long as height of eye and 1.3× as long as basal width of mandible; frons smooth, except for some fine rugulae.

Mesosoma. Mesosoma 1.4× as long as high in lateral view; mesoscutum granulate and with rather long, narrow, medio-posterior groove (Fig. 3); notauli shallow, complete, largely smooth and anteriorly connected to lateral irregular carina; scutellar sulcus with 3 carinae; scutellum finely striate antero-laterally and superficially granulate medially (Fig. 3); propodeum granulate and with large areola, its median carina much shorter than anterior side of areola (Fig. 3); side of pronotum rugose-crenulate and secondary granulate sculpture; mesopleuron largely smooth and convex (Fig. 1); precoxal sulcus rather deep and only anterior half present, with few crenulae; metapleuron densely rugulose and with long setae; mesosternal sulcus deep, narrow and smooth. Wings. Fore wing: pterostigma elongate triangular and 4× longer than wide (Fig. 2), r issued near its middle and 1.2× longer than width of pterostigma; 2-SR complete and sclerotized left wing) or only basal two-thirds pigmented (right wing, Fig. 2); 3-SR 1.6× longer than r; SR1 straight and reaching tip of wing; m-cu distinctly postfurcal, rather short (Fig. 2); subdiscal cell distally closed, CU1b close to m-cu and CU1a at same level as 2-CU1 (Figs 1, 2). Legs. Hind coxa largely smooth; length of femur, tibia and basitarsus of hind leg 5.5, 11.4, and 10.2× their width, respectively; hind tarsus compressed.

Metasoma. Length of first tergite 0.6× its apical width, its surface longitudinally striate and with additional granulate sculpture between striae, dorsal surface evenly convex, its dorsal carinae lamelliform and medially interconnected; medial length of second tergite 0.9× its basal width, and 1.4× as long as third tergite; second and third tergites longitudinally striate (but on middle of third tergite weakly developed) and secondary granulate sculpture; second transverse suture coarsely crenulate and nearly straight (Fig. 4); third tergite antero-laterally without minute, tooth-shaped protuberance and distinctly narrowed posteriorly (Figs 4, 5), with narrow, rugulose, and rather dull apical rim medially (Fig. 5) and distinctly serrate latero-apically (Fig. 4); apical lamella of third metasomal tergite distinctly protruding laterally (Fig. 1), concave and wide in dorsal view, with approx. 25 carinae (Figs 4, 5); setose part of ovipositor sheath 0.23 × as long as fore wing and 0.5 × as long as hind tibia, nearly parallel-sided (Fig. 1).

Colour. Yellowish brown; third tergite mainly yellowish brown but laterally darkened, not contrasting with similarly coloured second tergite (Figs 1, 5, 26); mesosoma brown, but mesoscutum and scutellum largely dark brown; antenna (basal segments yellowish), pterostigma (but basal quarter yellow) and veins M+CU1 apically, 1-CU1, 1-SR, 1-M, r, and veins of apical half of fore wing dark brown (Fig. 2); palpi and tarsi pale yellowish; remainder of legs yellowish brown; wing membrane infuscate, but with subhyaline band below base of pterostigma (Fig. 1).

Variations. Antenna with 16–17 segments; length of body 2.1–2.3 mm, and of fore wing 1.6–1.7 mm; length of ovipositor sheath 0.21–0.23× as long as fore wing; vein 2-SR of fore wing varies in reared series from nearly complete to entirely absent (Fig. 2), most frequently only basal half present as pigmented but unsclerotised vein; notauli complete to posterior third obsolescent; second metasomal tergite 1.3–1.5× longer than second tergite; lamella of third tergite more or less serrate (Figs 1, 5).

Male. Very similar to female, but metasoma slenderer (Fig. 11); head dark brown dorsally; third tergite more or less darkened in ♂ (Fig. 9), striate and/or granulate and its lamella serrate and with approx. 20 carinae (Figs 9–11); pterostigma dark brown basally.

Finland, Germany, Moldova, *Sweden.

Five specimens of Lysitermus pallidus hatched from ten final instar larval cases of Diplodoma laichartingella (Goeze, 1783) (Lepidoptera, Psychidae) collected in Sweden by the second author. Dissection of the final instar larval cases showed that only three had been parasitized and five specimens had hatched from them. It clearly indicates that L. pallidus is a gregarious larval ectoparasitoid of this host, but probably a facultative one perhaps depending on the size (first- or second-year stage?) of the host. In northern Europe D. laichartingella has a two-year life cycle which raises the question of whether L. pallidus is a parasitoid only of fully grown larva and, therefore, has a two-year lifecycle like its host (Kunz 1989) or whether it might be able to complete its lifecycle in a juvenile larval case as well. The D. laichartingella cases are usually found in woodland areas where the caterpillar feeds on algae/mosses as well as dead insects on tree trunks, especially, of Fagus sylvatica L. and Quercus robur L. The specimen from Finland has also been reared from D. laichartingella (det. M. Mutanen) but was referred by Gupta and Quicke (2018) as reared from an unidentified psychid host.

1 ♀ (FMNH), “Finland: Ab, Parainen, Pexor, 60.26°N, 22.25°E, Malaise trap 1a, 25.vi.–6.vii.2020, Juho Paukkunen”; 1 ♀ (CSV), same label data, but 6–19.vii.2020, Juho Paukkunen & Jonathan Scotson; 1 ♀ + 1 ♂ (RMNH), “S. Sweden: Uppland, Edsbro, Kristineholm, S15 or S20, coll. 28.i.2009, ex Inonotus radiatus on Alnus glutinosa, C. Gonzales Alonso, RMNH’11”; 1 ♂ (RMNH), “Netherlands: UT, UTM FF 6560, Amerongen, unmanaged Quercus robur [forest], ex dead stem [in] cage 9(h), 29.v.–12.vi.2001, L. Moraal, RMNH’02”; 1 ♀ (NMS), “France: Lot-et-Garonne, Bernac, 28.vii.[19]90, M.R. Shaw”; 1 ♀ + 2 ♂ (RMNH), “Spain, Llansa, 1986, ex Luffia lapidella, H. Hendrickx, RMNH’96”; 1 ♀ (RMNH), “Portugal, Oeiras, 18–22.viii.1979, A. van Harten”; 9 ♀ + 4 ♂ (RMNH), “Portugal, Cascais fort, ex Luffia lapidella, coll. 27.vii.1994, H. Hendrickx”; 5 ♀ + 3 ♂ (RMNH), idem, but coll. 4.v.1995, ex Luffia sp.; 1 ♀ (RMNH), idem, but coll. 1.iii.1995; 10 ♀ + 2 ♂ (RMNH, ZJUH), idem, but Cascais (and mislabelled as from Azores), ex Luffia ferchaultella (Psych.), coll. 27.vii.1994, em. 21.viii.1994; 2 ♀ (RMNH, MTMA) “Italy: Sardinia centr., Bruncu Istiddi, 900 m, ex Luffia sp. n.?, viii.1975, E. Hartig & Gozmany”; 1 ♀ + 1 ♂ (NMS), “Malta, Buscett, 22.xi.2006, ex larva on Luffia lapidella (Goeze, 1783) [Psychidae], M. Zerafa”; 2 ♀ + 1 ♂ (NMS), “Malta: Mosta valley, larva on Eudarcia derrai (Gaedike, 1983) [Tineidae], coll. 22.ii.2010, em. v.2010, M. Zerafa”; 3 ♀ + 5 ♂ (BZL, NMS), “Romania: Siebenbürgen, Munt Apuseni (Trascaului), Umg. Posaga 2 km oberhalb, 600 m, ex Dahlica rakosy oder Apt. helicoidella [Psychidae], em. Ende April 2005, M. Weidlich”; 2 ♀ + 1 ♂ (BZL, NMS), “Bulgaria: Macedonia, Pirin planina – Süd, Umg. Jane Sandanski, 1220 m, el. 13.v.2000, M. Weidlich, ex Dahlica sp. [Psychidae]”.

Figured ♀ from France (NMS), length of body 1.6 mm and of fore wing 1.4 mm.

Head. Antenna 1.1× as long as fore wing, with 15 segments, rather widened apically (Fig. 12), scapus oblique apically, length of third segment 1.1× fourth segment; third, fourth and penultimate segments 5.0, 4.5, and 3.1× their width, respectively; face largely smooth, with long erect setae and 1.7× wider than high; clypeus smooth, upper half distinctly convex and ventral half depressed; head in dorsal view 1.8× broader than long medially, eye 1.4× longer than temple dorsally, strongly and roundly narrowed posteriorly (Fig. 18); vertex smooth and shiny, including area near stemmaticum (Fig. 18); occipital carina moderately strong and in front of it indistinctly micro-crenulate; POL: diameter of posterior ocellus: OOL = 2:2:3; eye in lateral view 1.6× as high as wide, temple distinctly broadening ventrally, smooth and width of eye 1.6× minimum width of temple laterally (Fig. 12); malar space 0.4× as long as height of eye and 1.5× as long as basal width of mandible; frons smooth and shiny.

Figure 12. 

Lysitermus tritoma (Bouček), ♀, France, habitus lateral. Photograph: R. Soethof.

Mesosoma. Mesosoma 1.5× as long as high in lateral view; mesoscutum granulate and with 2 rather short carinulae and no medio-posterior groove (Fig. 14); notauli shallow, distinctly developed anteriorly and posterior half obsolescent, largely smooth and anteriorly connected to lateral irregular carina; scutellar sulcus with 1 carina; scutellum smooth and shiny, convex (Fig. 14); propodeum shiny, largely smooth between carinae and with large areola, its median carina approx. as long as anterior side of areola (Fig. 14); side of pronotum rugose-crenulate and with some granulate sculpture; mesopleuron largely smooth and convex (Fig. 12); precoxal sulcus rather deep and only in anterior half present, with few crenulae anteriorly; metapleuron largely smooth and with long setae; mesosternal sulcus deep, narrow and smooth. Wings. Fore wing: pterostigma elongate triangular and 3.5× longer than wide (Fig. 13), r issued from its middle and slightly longer than width of pterostigma; 2-SR completely absent (Fig. 13); 3-SR 1.5× longer than r; SR1 straight and reaching tip of wing; m-cu rather short (Fig. 13); subdiscal cell distally closed, CU1b close to m-cu and CU1a at same level as 2-CU1 (Fig. 13). Legs. Hind coxa largely smooth; length of femur, tibia and basitarsus of hind leg 5.0, 9.2, and 5.2× their width, respectively; hind tarsus hardly compressed.

Figures 13–18. 

Lysitermus tritoma (Bouček), ♀, France 13 wings 14 mesosoma dorsal 15 propodeum and metasoma dorsal 16 second and third metasomal tergites dorsal 17 head anterior 18 head postero-dorsal. Photographs: R. Soethof.

Metasoma. Length of first tergite 0.6× its apical width, its dorsal surface evenly convex, surface longitudinally striate and with additional granulate sculpture between striae, its dorsal carinae lamelliform and medially interconnected; medial length of second tergite 0.9× its basal width, and 1.4× as long as third tergite; second and third tergites longitudinally striate and with distinct secondary granulate sculpture; second transverse suture coarsely crenulate and nearly straight (Fig. 15); third tergite antero-laterally without minute tooth-shaped protuberance and distinctly narrowed posteriorly (Figs 15, 16), with distinct smooth and shiny apical rim (Fig. 15); apical lamella of third metasomal tergite moderately protruding laterally (Fig. 12), concave and wide in dorsal view, with approx. 8 carinae (Fig. 16); setose part of ovipositor sheath 0.21× as long as fore wing and 0.6× as long as hind tibia, slightly widened apically (Fig. 12).

Colour. Dark brown; third tergite dark brown, contrasting with largely yellowish brown second tergite (Figs 15, 16); first tergite yellowish brown; antenna (basal segments yellowish), pterostigma (but basal fifth yellow) and veins M+CU1 apically, 1-CU1, 1-M, and veins of apical half of fore wing dark brown (Fig. 13); palpi and tarsi pale yellowish; remainder of legs yellowish brown; wing membrane infuscate, but band below base of pterostigma and marginal cell partly, subhyaline (Fig. 13).

Variations. Antenna with 14–17 segments; length of body 1.5–1.9 mm, and of fore wing 1.3–1.5 mm; length of ovipositor sheath 0.21–0.26× as long as fore wing; vein 2-SR of fore wing varies from completely absent (Figs 13, 19), complete (Fig. 29) to small unsclerotised trace (Fig. 45); notauli complete to posterior third obsolescent; scutellar sulcus with 1–3 carinae; precoxal sulcus smooth or with few crenulae; metapleuron largely smooth or with some rugulae medially; median carina of propodeum approx. as long as anterior side of areola or much shorter; second metasomal tergite 1.3–1.5× longer than second tergite; lamella of third tergite hardly serrate (Fig. 12), with 8–16 carinae; colour of body is very variable: southern specimens are brownish yellow with only third tergite dark brown and northern specimens are largely dark brown (except first and second tergites, but in both Finnish specimens also darkened; Figs 27–29), sometimes hind coxa, femur and tibia largely brown or dark brown (Fig. 29).

Figures 19–21. 

Lysitermus tritoma (Bouček), ♂, Malta 19 habitus dorso-lateral 20 propodeum and metasoma dorsal 21 second and third metasomal tergites dorsal. Photographs: R. Soethof.

Male. Very similar to female, but metasoma slenderer (Fig. 20); antenna with 16 or 17 segments; length of body 1.4–1.6 mm, and of fore wing 1.3 mm; head dark brown dorsally; linear medio-posterior depression of mesoscutum absent or slightly impressed; third tergite dark brown and contrasting with yellowish second tergite (Fig. 20), striate and/or granulate and its lamella hardly serrate (Figs 19–21, 45); pterostigma dark brown basally.

Reared from lepidopterous case-bearing larvae belonging to Psychidae (Luffia ferchaultella (Stephens, 1850); L. lapidella (Goeze, 1783); L. sp.; Dahlica sp.) and Tineidae (Eudarcia derrai (Gaedike, 1983); Mifsud et al. 2019). It has been reared from Inonotus radiatus bracket fungi on Alnus glutinosa (L.) (Jonsell et al. 2016), most likely from host cases hiding in the fungi.

*Bulgaria, Czech Rep., *Finland, *France, Italy (Sardinia), Malta, *Netherlands, Poland, *Portugal (mainland), *Romania, *Spain (mainland), Sweden.

The medio-longitudinal carina of the propodeum is very variable in length, from about as long as oblique anterior side of propodeal areola to much shorter and the second metasomal suture varies from distinctly sinuate (typical L. tritoma; Figs 24, 25) to straight (typical L. suecicus; Figs 15, 20, 22). After more reared specimens became available, intermediates of both characters have been found, and there are no grounds to separate any longer the two species, as has been proposed by van Achterberg (1991).

Figures 22–25. 

Lysitermus tritoma (Bouček), ♀, 22 holotype L. suecicus, 23–25 types of L. tritoma 22 habitus dorsal 23 metasoma lateral 24, 25 detail third tergite dorsal. 22 from Forshage et al. (2016) and 23–25 from Bouček (1956).

The holotype of L. suecicus (NRS) is incorrectly figured in the original description. For instance, the second tergite is not twice as long as the third tergite but 1.5× (Fig. 22), the ovipositor sheath is not widened but subparallel, and the pterostigma is not robust but rather slender (Fig. 22).

Figures 26–27. 

26 Lysitermus pallidus Foerster, ♀, Sweden (freshly emerged specimen), habitus lateral 27 L. tritoma (Bouček), dark ♀, Finland, metasoma dorsal. Photographs: F. Skeppstedt (26) and P. Malinen (27).

Figures 28–29. 

Lysitermus tritoma (Bouček), dark ♀, Finland 28 body dorsal 29 habitus lateral. Photograph: P. Malinen.

Holotype of Prolysitermus talitzkii, ♂ (ZISP), “MCCP [= Moldova], Kishinev, radiolu, 2.vi.[19]62, 65, Talitzkij”, “Holotypus Praelysitermus [sic!] talitzkii Tobias, [19]71”; 1 ♂ paratype of P. talitzkii (ZISP) from Moldova, Străşeni, 21.vii.1961. Holotype of Prolysitermus longiventris, ♂ (ZISP), “[Russia:] Sochi-Lazarevskoe, 3–4.v.[1]973, V. Tobias”, “Prolysitermus longiventris sp. n., Tobias, det. 1973”, “Holotypus Prolysitermus longiventris Tobias, 1976”; 1 ♀ paratype (ZISP), “28.iv.[19]75”, “[Russia:] Krasnodarskiy kray, Lazarevskoe, les na terrasirovannych sklonach, 28.iv.1975, V. Tobias”, “Paratypus Prolysitermus longiventris Tobias, 1976”; 1 ♂ paratype (ZISP), “11.v.[19]75”, and same label data as ♀ paratype.

Paratype ♀ of L. longiventris, length of fore wing 1.4 mm, and of body 1.6 mm.

Head. Antenna 1.1× as long as fore wing, with 15 segments, rather widened apically (Fig. 30), scapus oblique apically, length of third segment 1.1× fourth segment; third, fourth, and penultimate segments 6.6, 5.8, and 2.9× their width, respectively; face largely smooth, with long erect setae and 2.2× wider than high; clypeus smooth and distinctly convex; head in dorsal view 1.6× broader than long medially, eye 1.4× longer than temple dorsally, strongly and roundly narrowed posteriorly (Fig. 32); vertex smooth and shiny, including area near stemmaticum (Fig. 32); occipital carina strong medio-dorsally and in front of it micro-crenulate; POL:diameter of posterior ocellus: OOL = 20:12:35; eye in lateral view 1.5× as high as wide, temple distinctly broadening ventrally, smooth, and width of eye 1.3× minimum width of temple laterally; malar space 0.5× as long as height of eye and 1.7× as long as basal width of mandible; frons smooth and shiny.

Mesosoma. Mesosoma 1.5× as long as high in lateral view; mesoscutum granulate and shiny, medio-posteriorly with indistinct groove (Fig. 32); notauli only anteriorly distinct, largely smooth, but anteriorly crenulated; scutellar sulcus with one median carina and 6 weak crenulae; scutellum largely smooth and shiny, convex (Fig. 32); propodeum shiny, largely smooth between carinae and with large areola, its median carina shorter than anterior side of areola; side of pronotum and mesopleuron largely smooth; precoxal sulcus rather shallow and only its anterior half present, largely smooth; metapleuron largely smooth and with long setae. Wings. Fore wing: pterostigma elongate triangular and 5.0× longer than wide (Fig. 30), r issued from its middle and 0.7× shorter than width of pterostigma; 2-SR absent except for some pigmentation (Fig. 30); 3-SR 3.1× longer than r; SR1 straight and reaching tip of wing; m-cu rather short and largely unpigmented; subdiscal cell distally closed, CU1b far from m-cu and CU1a above level of 2-CU1 (Fig. 30). Legs. Hind coxa largely smooth; length of femur, tibia and basitarsus of hind leg 4.5, 11.1, and 8.4× their width, respectively; hind tarsus compressed.

Figures 30–32. 

Lysitermus talitzkii (Tobias), ♀, paratype of L. longiventris 30 habitus lateral 31 metasoma dorsal 32 head and mesoscutum dorsal. Photographs: K. Samartsev.

Metasoma. Length of first tergite 0.6× its apical width, its surface longitudinally striate and with additional granulate sculpture between striae, dorsal surface evenly convex, its dorsal carinae lamelliform and medially interconnected anteriorly; medial length of second tergite 0.9× its basal width, and 1.4× as long as third tergite; second and third tergites longitudinally striate and with distinct additional granulate sculpture between striae; second transverse suture coarsely crenulate and nearly straight (Fig. 31); third tergite antero-laterally with minute tooth-shaped protuberance and gradually narrowed posteriorly (Fig. 31), with distinct and sculptured posterior rim; apical lamella of third metasomal tergite moderately protruding laterally (Fig. 31), straight and narrow medially in dorsal view, with approx. 14 carinae; setose part of ovipositor sheath 0.4× as long as hind tibia.

Colour. Mainly dark brown; third tergite dark brown, contrasting with largely yellowish brown second tergite (Figs 30, 31); first tergite yellowish brown; scapus infuscated, pedicellus, third and fourth segments yellow; remainder of antenna, pterostigma, and veins M+CU1 apically, 1-CU1, 1-M, and veins of apical half of fore wing brown; palpi and tarsi pale yellowish; remainder of legs yellowish brown; wing membrane subhyaline.

Male. Colour very variable: body entirely dark brown (Fig. 43) to partly yellowish brown (Fig. 45); metasoma slender, darkened and antero-lateral small tooth-like protuberance of third tergite either absent (holotypes, but area slightly convex; Figs 36, 47) or present (Fig. 44); first tergite weakly narrowed posteriorly (Figs 36, 44) or parallel-sided (Fig. 47); vein 3-SR of fore wing 1.4–3.0× longer than vein r (Figs 34, 43, 45); length of body1.4–1.9 mm and fore wing 1.4–1.5 mm.

Figure 33. 

Lysitermus talitzkii (Tobias), ♂, holotype of L. longiventris, habitus lateral. Photograph: K. Samartsev.

Unknown.

Moldova, Poland (Huflejt 1997), Russia.

Figures 34–42. 

Lysitermus talitzkii (Tobias), ♂, holotype of L. longiventris 34 fore wing 35 head and mesosoma lateral 36 propodeum and first and second metasomal tergites dorsal 37 metasoma dorso-lateral 38 metasoma lateral 39 metasoma dorso-lateral 40 head anterior 41 head and mesonotum dorsal 42 hind coxa and femur lateral. Photographs: K. Samartsev.

The male holotype of L. talitzkii (Tobias, 1971) was considered to be a synonym of L. pallidus Foerster by Belokobylskij and Tobias (1986) and van Achterberg (1991), but after examination of reared series consisting of both sexes it is obvious that the holotype male with its gradually widened hind tibia (Fig. 45) fits better with L. longiventris, as defined above, and the latter is synonymised with it. The holotype has the notauli shallowly impressed posteriorly (van Achterberg 1995) although normally the posterior half of the notauli are absent, but specimens with vaguely to distinctly indicated notauli have been examined among specimens of the closely related L. tritoma from Sweden (holotype of L. suecicus), Italy, and Portugal, and, therefore, we do not consider the more developed notauli as a valid reason to maintain L. longiventris as a species different from L. talitzkii.

Figures 43–44. 

Lysitermus talitzkii (Tobias), ♂, paratype of L. longiventris 43 habitus lateral 44 metasoma dorsal. Photographs: K. Samartsev.

Lysitermus longiventris (Tobias) was described from N. Caucasus and is very similar to L. tritoma (Bouček) but differs by having the third metasomal tergite often with a minute tooth-like protuberance antero-laterally and its posterior lamella straight medially or nearly so, the metasoma slightly slenderer, the third tergite slightly less narrowed posteriorly, and vein 3-SR of the fore wing usually more than twice as long as vein r. The reduction of the longitudinal rugae on the third tergite is considered less distinctive because reduction of sculpture is common in Lysitermus males and to a lesser degree in females. Other differences given by Belokobylskij and Tobias (1986), such as the first tergite as long as wide at apex and the second tergite longer than its apical width, disagree with the only figure in the very short original description and the figures included here (Figs 31, 36, 44). Characters such as the third tergite less sculptured than second tergite and without distinct lamella apically, the face twice as wide as high, and the width of the hypoclypeal depression equal to distance from eye to depression are more or less also found in males of L. tritoma.

Figures 45–47. 

Lysitermus talitzkii (Tobias), ♂ holotype, but 47 of ♂ paratype 45 habitus lateral 46, 47 metasoma dorsal. Photographs: K. Samartsev.