Lysitermus Foerster, 1863

Achterberg, Cornelis van, Skeppstedt, Fredrik & Vaeaenaenen, Simo, 2021, Revision of the Palaearctic species of Lysitermus Foerster (Hymenoptera, Braconidae, Hormiinae), ZooKeys 1040, pp. 65-89 : 67-68

publication ID	https://dx.doi.org/10.3897/zookeys.1040.66274
publication LSID	lsid:zoobank.org:pub:63E20193-A7C8-420F-99C3-23ED54706BB4
persistent identifier	https://treatment.plazi.org/id/CF439742-C97F-5F30-9E7D-0F5A2E210B08
treatment provided by	ZooKeys by Pensoft
scientific name	Lysitermus Foerster, 1863
status

Treatment

Lysitermus Foerster, 1863 View in CoL Figs 1 View Figure 1 , 2-8 View Figures 2–8 , 9-11 View Figures 9–11 , 12 View Figure 12 , 13-18 View Figures 13–18 , 19-21 View Figures 19–21 , 22-25 View Figures 22–25 , 26-27 View Figures 26–27 , 28-29 View Figures 28–29 , 30-32 View Figures 30–32 , 33 View Figure 33 , 34-42 View Figures 34–42 , 43-44 View Figures 43–44 , 45-47 View Figures 45–47

Lysitermus Foerster, 1863: 236 [not Tobias 1971: 205, 1976: 49]; Hedqvist 1963: 35; Shenefelt 1975: 1154-1155; van Achterberg 1982: 125; Belokobylskij and Tobias 1986: 63-64; van Achterberg 1991: 19, 1995: 93; Jonsell et al. 2016: 12, 18; Forshage et al. 2016: 12. Type species (by monotypy): Lysitermus pallidus Foerster, 1863 [examined].

Rogadinaspis Bouček, 1956: 441; Hedqvist 1963: 35 (as synonym of Lysitermus Foerster, 1863); Shenefelt 1975: 1155; van Achterberg 1991: 19, 1995: 93. Type species (by monotypy): Rogadinaspis tritoma Bouček, 1956 [examined].

Paracedria Hedqvist, 1957: 219; Hedqvist 1963: 35 (as synonym of Lysitermus Foerster, 1863); Shenefelt 1975: 1155; van Achterberg 1991: 19, 1995: 93. Type species (by monotypy): Paracedria suecicus Hedqvist, 1957 [examined].

Prolysitermus Tobias, 1971: 205-206; Shenefelt 1975: 1155; Tobias 1976: 49; van Achterberg 1982: 125 (as synonym of Lysitermus Foerster, 1863), 1991: 19, 1995: 93. Type species (by monotypy): Prolysitermus talitzkii Tobias, 1971 [examined].

Diagnosis.

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.

Biology.

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.

Notes.

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 View Figures 2–8 ) 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 View Figures 2–8 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).

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).

Key to Palaearctic species of the genus Lysitermus Foerster

1	Area behind stemmaticum finely granulate and more or less rugulose anteriorly (Fig. 8 View Figures 2–8 ); scutellum finely striate antero-laterally and granulate medially (Fig. 3 View Figures 2–8 ); apical lamella of third metasomal tergite in ♀ distinctly protruding laterally (Fig. 1 View Figure 1 ), with approx. 25 carinae and wide in dorsal view (Figs 4 View Figures 2–8 , 5 View Figures 2–8 ), its border distinctly serrate in lateral view (also in ♂ comparatively wide, but in lateral view less serrate, without smooth apical rim; Figs 9-11 View Figures 9–11 ); third tergite of ♀ mainly yellowish brown, less contrasting with second tergite (Figs 1 View Figure 1 , 5 View Figures 2–8 , 26 View Figures 26–27 ; more or less darkened in ♂: Fig. 9 View Figures 9–11 )	L. pallidus Foerster, 1863
-	Area behind stemmaticum smooth or largely so (Figs 18 View Figures 13–18 , 32 View Figures 30–32 , 41 View Figures 34–42 ); scutellum smooth, without lateral striae (Figs 14 View Figures 13–18 , 28 View Figures 28–29 , 32 View Figures 30–32 , 36 View Figures 34–42 , 41 View Figures 34–42 ), but rarely granulate medially; apical lamella of third tergite less protruding laterally (Figs 12 View Figure 12 , 19 View Figures 19–21 , 23 View Figures 22–25 , 29 View Figures 28–29 , 30 View Figures 30–32 , 39 View Figures 34–42 ), with 8-16 carinae and medium-sized in dorsal view (Figs 16 View Figures 13–18 , 21 View Figures 19–21 , 24 View Figures 22–25 , 25 View Figures 22–25 , 27 View Figures 26–27 , 31 View Figures 30–32 ), usually straight to slightly serrate in lateral view (Figs 12 View Figure 12 , 29 View Figures 28–29 , 30 View Figures 30–32 , 39 View Figures 34–42 ); third tergite dark brown or brown, darker than yellowish brown second tergite (Figs 15 View Figures 13–18 , 20 View Figures 19–21 , 22 View Figures 22–25 , 31 View Figures 30–32 ), but in melanistic specimens second tergite more or less dark brown (Figs 27 View Figures 26–27 - 29 View Figures 28–29 , 39 View Figures 34–42 , 43 View Figures 43–44 )	2
2	Apical lamella of third metasomal tergite concave medio-posteriorly (Figs 16 View Figures 13–18 , 21 View Figures 19–21 , 24 View Figures 22–25 ), but sometimes intermediate (Figs 25 View Figures 22–25 , 27 View Figures 26–27 ) and with a distinct and smooth rim in front of it (Figs 15 View Figures 13–18 , 20 View Figures 19–21 , 23 View Figures 22–25 , 27 View Figures 26–27 ); hind tibia (except apically) parallel-sided or nearly so (Figs 12 View Figure 12 , 29 View Figures 28–29 ); third antennal segment yellow or yellowish brown (Figs 12 View Figure 12 , 17 View Figures 13–18 , 19 View Figures 19–21 , 22 View Figures 22–25 , 29 View Figures 28–29 ), rarely mainly dark brown; vein 3-SR of fore wing 1.3-2.0 × longer than vein r (Figs 13 View Figures 13–18 , 22 View Figures 22–25 )	L. tritoma ( Bouček, 1956)
-	Apical lamella of third metasomal tergite straight medio-posteriorly or nearly so (Figs 31 View Figures 30–32 , 37 View Figures 34–42 , 39 View Figures 34–42 , 44 View Figures 43–44 , 47 View Figures 45–47 ) and rim in front of it less developed and more or less sculptured (Figs 30 View Figures 30–32 , 31 View Figures 30–32 , 33 View Figure 33 , 37 View Figures 34–42 , 46 View Figures 45–47 , 47 View Figures 45–47 ); hind tibia gradually widened (Figs 30 View Figures 30–32 , 45 View Figures 45–47 ); third antennal segment dark brown or largely so (Figs 33 View Figure 33 , 45 View Figures 45–47 ); vein 3-SR of fore wing usually 2.3-3.0 × longer than vein r (Figs 30 View Figures 30–32 , 33 View Figure 33 , 34 View Figures 34–42 ), but sometimes approx. 1.4 × (Figs 43 View Figures 43–44 , 45 View Figures 45–47 )	L. talitzkii (Tobias, 1971), stat. nov.