Liosphex Townes, 1977

Lohrmann, Volker & Ohl, Michael, 2010, World revision of the wasp genus Liosphex Townes, 1977 (Hymenoptera: Rhopalosomatidae), Zootaxa 2384, pp. 1-43 : 4-6

publication ID	https://doi.org/ 10.5281/zenodo.193731
DOI	https://doi.org/10.5281/zenodo.6209697
persistent identifier	https://treatment.plazi.org/id/03B3C46B-390C-1C0A-FF67-213BD80B0CC1
treatment provided by	Plazi
scientific name	Liosphex Townes, 1977
status

Treatment

Genus Liosphex Townes, 1977 View in CoL View at ENA

Liosphex Townes, 1977: 10 View in CoL . Type species: Liosphex varius Townes, 1977 View in CoL , by original designation.

Diagnosis. The genus Liosphex is unique among all genera of Rhopalosomatidae in the combination of the following characters: occipital carina absent (present in all other extant genera); ocelli of moderate size, OOD 1.8–2.6× LOD ( Figs 1–2 View FIGURES 1 – 7 ; the ocelli of the brachypterous genus Olixon are markedly reduced in size or lacking, in the other two fully winged genera the ocelli are large, except in Paniscomima seyrigi ); inner margin of compound eye with a deep notch above the antennal socket, the dorsal margin of the notch is extremely shorter than the ventral margin ( Fig. 1 View FIGURES 1 – 7 ; the inner eye margin of Olixon is straight, in the other two genera the margins of the eye notch are more or less of equal length).

Description of the female. Head ( Figs 1–2 View FIGURES 1 – 7 ): Maximum width in frontal view 1.5–1.9 mm. Inner eye margin with deep scalene notch above torulus ( Fig. 2 View FIGURES 1 – 7 ). Ventral margin of eye almost reaching clypeus. UID 1.05–1.8× as long as LID. MOD almost of same size as LOD. OOD 1.8–2.6× LOD. Vertex with impression laterally of hind ocellus. Frons with slight median longitudinal impression ( Fig. 1 View FIGURES 1 – 7 ). Ventral margin of clypeus slightly concave ( Fig. 2 View FIGURES 1 – 7 ). Mandible with four teeth, most inner tooth very small but clearly present. Occipital carina absent. Outer region of occiput convex, inner area concave. Apex of flagellomeres I–V with two bristles each (in some specimens also on further flagellomeres), outer bristle longer than inner bristle. Head covered with dense, short setae, which are longer on clypeus and lacking on occiput. Apical section of mandible with long setae. Article II of labial palpus with one thick long bristle, article and bristle almost of same length.

Mesosoma ( Figs 11–13 View FIGURES 8 – 13 ): Maximum length 2.4–3.3 mm. Pronotum with collar and streptaulus. Ventral margin of pronotum with acute angle. Posterior margin of pronotum strongly concave and weakly sclerotized. Parapsidialsulcus present. Transition between mesoscutum and scutellum regular without any cavity. Scutellum in dorsal view trapezoidal, its posterior margin weakly rounded. Metanotum wider than long, with posterior transverse, membraneous section. Metepimeron triangular, its posterior angle slightly rounded.

Forewing ( Figs 3, 5–10 View FIGURES 1 – 7 View FIGURES 8 – 13 ): Maximum length 5.5–9.0 mm. Forewing with eight (in some specimens nine) enclosed cells ( Fig. 3 View FIGURES 1 – 7 ): costal (C) narrow at base and slightly wider at distal section but over complete distance narrower than bordering veins, radial (R), first cubital (1 Cu), second cubital (2 Cu) apically not completely enclosed by a tubular vein, first median (1M), first radial 1 (1R1), first radial 2 (2 R1), and first radial sector (1Rs). Some specimens with additional cell present at distal apex of 1M ( Fig. 3 View FIGURES 1 – 7 ; named 1M-a within this work). At least anterodistal part of forewing slightly infuscate. Wing membrane covered and ventral margin rendered with short, evenly distributed setae.

Hindwing ( Fig. 4 View FIGURES 1 – 7 ): With two complete cells: R and Cu, Costal cell only present as membranous area anterior to Sc+R but not enclosed by C. Jugal and anal lobe present. Anal lobe more than twice as long as jugal lobe. Sc+R tubular and pigmented, at its basal two thirds fused with C. R tubular on its basal section as long as with distal hamuli. Rs tubular, straight and reclivous at basal section, distal section not tubular but markedly pigmented. M+Cu tubular and pigmented from base to intersection of M, distally not tubular but markedly pigmented. Distal section of M only present as slightly pigmented remnant. Cu-a tubular but not pigmented. Basal hamuli straight, their length continuously increasing distad. Distal hamuli curved, hookshaped; similar in size and form. Wing membrane covered and ventral margin rendered with short regularly distributed setae.

Legs: Posterolateral margin of coxae with a few long bristles. Forefemur swollen and slightly concave on anterior side. Dorsal side of femura, anterior side of tibiae and hindbasitarsus with thick bristles. Tarsomeres II–V flattened, with dense erect setae on ventral side. Tarsomeres II–IV slightly narrowed, tarsomere V parallel sided and with large aroleum.

Metasoma: Tergite I 1.2–2.3× as long as wide, with posterior median impression. Posterior margin of sternum V concave. Sting upcurved.

Color: Variable, ranging from stramineous or pale brown species with black markings to almost black species with whitish, orange or reddish brown markings.

Description of the male. As in females except for the following:

Head: Maximum width in frontal view 1.0– 1.6 mm. Apical bristles on flagellomeres shorter than in females, longer bristle on flagellomere I not longer than 0.65× flagellomere length.

Mesosoma: Maximum length 1.8–2.7 mm. Forefemur not swollen. Tarsomeres rounded, not flattened. Plantulae at least present on tarsomeres II–IV. Tarsal claws bifurcated, aroleum rather small.

Wings: Maximum length of forewing 4.0–7.0 mm.

Metasoma: Posterior margin of sternite VII with row of thick bristles. Parameres upcurved.

Distribution ( Figs 69–72 View FIGURE 69 View FIGURE 70 View FIGURE 71 View FIGURE 72 ). The genus is only known from two islands in Southeast Asia (Borneo and Mindanao) and the New World, where the distribution ranges from southeastern USA to Southern Brazil ( Brazil, Colombia, Costa Rica, Ecuador, El Slavador, Mexico, Panama, Paraguay, Peru and USA (Arkansas, Florida, Louisiana and Mississippi) ( Townes 1977, Gauld 1995, MacGown 1998, Guidotti 1999, Fernández & Sarmiento-M. 2002, Cambra 2005, Pilgrim et al. 2008 and Lohrmann & Ohl 2009). In this study, Liosphex is recorded from Argentina for the first time. Kentucky, a new state record of the genus in the USA, is shown to be the most northern distribution limit of Liosphex .

Life History. Almost nothing is known about the biology of Liosphex . Since species of Olixon and Rhopalosoma are evidently ectoparasitoids of crickets ( Perkins 1908, Hood 1913, Gurney 1953, Alexander & Otte 1967, Freytag 1984), this life mode is also suspected to be present in Liosphex . There is only little information given on the data label on the habitat of the investigated specimens. Most of the more than 150 specimens of L. varius have been collected in ravine hard- or mixed woods whereas some have also been caught in a regrown oak forest (eight specimens), in rosemary/turkey oak stands (one specimen) or spine/oak scrubs. Liosphex boreus has been collected in an oak-hickory forest whereas L. bribri is reported with one specimen from rainforest. Most specimens have been collected in Malaise traps, only a few with black- and sunlight lamps. This fact and the nocturnal life style of their suspected hosts may indicate that at least some species of Liosphex are nocturnal, as suspected for other rhopalosomatid genera. Some specimens of Liosphex are recorded from up to 3350m (11.000ft) in the highlands of South Mexico but most of the records are from below 1000m.