Oberthuerella transiens (Benoit)

Buffington, Matthew L. & Noort, Simon van, 2012, Revision of the Afrotropical Oberthuerellinae (Cynipoidea, Liopteridae), ZooKeys 202, pp. 1-154 : 72-76

Oberthuerella transiens (Benoit) Figures 35-36

Tessmannella transiens Benoit, 1955: 283. New combination by Ronquist (1995).

Description.

Coloration of head, mesosoma, and metasoma black to dark brown; legs reddish brown. Sculpture on vertex, lateral surface of pronotum and mesoscutum present, deeply striate on head, costate with foveae on pronotum, mesoscutum.

Head. Broadly triangular, in anterior view. Pubescence on head present, sparse setae scattered over head. Sculpture along lateral margin of occiput absent. Gena (measured from compound eye to posterolateral margin of head) short, ratio of length of gena to length of compound eye in dorsal view <0.3, in dorsal view. Sculpture of gena deeply striate with remnants of fovea. Lateral margin of occiput defined by distinctly angled, raised, sharp carina. Occiput (except extreme lateral margin) smooth. Ocelli small, ratio of maximum diameter of a lateral ocellus to shortest distance between lateral ocelli 0.2-0.4. Anterior ocellus close to posterior ocelli, posterior margin of anterior ocellus behind or subcontiguous with a transverse line running through anterior margins of posterior ocelli. Relative position of toruli close to ocelli, ratio of vertical distance between inner margin of torulus and ventral margin of clypeus to vertical distance between anterior ocellus and torulus <2.0. Median keel of face present, extending to middle of face, not reaching clypeus. Vertical carina adjacent to ventral margin of torulus absent. Facial sculpture almost entirely foveate, slightly horizontally striate along median keel. Facial impression absent, face flat. Antennal scrobe absent. Anterior tentorial pits large. Vertical delineations on lower face absent. Ventral clypeal margin laterally, close to anterior mandibular articulation, straight. Ventral clypeal margin medially emarginate. Clypeus horizontally striate. Malar space adjacent to anterior articulation of mandible evenly rounded, striate. Malar sulcus absent. Compound eye close to posterior ocellus, ratio of distance between compound eye and posterior mandibular articulation to distance between posterior ocellus and compound eye> 1.2. Compound eye, in dorsal view, distinctly protruding from the surface of the head, particularly laterally. Pubescence on compound eye absent. Orbital furrows absent. Lateral frontal carina of face absent. Dorsal aspect of vertex deeply foveate. Posterior aspect of vertex foveate. Hair punctures on lateral aspect of vertex absent. Posterior surface of head almost flat, not deeply impressed.

Labial-maxillary complex. Apical segment of maxillary palp with pubescence, consisting only of erect setae. Apical seta on apical segment of maxillary palp shorter than twice length of second longest apical seta. Erect setae medially on apical segment of maxillary palp present. Last two segments of maxillary palp (in normal repose) straight. Apical segment of maxillary palp more than 1.5 times as long as preceding segment.

Antenna. Articulation between flagellomeres in antenna connate with articles broadly joined. Male antenna composed of 12 flagellomeres. Placoidal sensilla absent. Second flagellomere of male antenna cylindrical. Length of second flagellomere of male antenna longer than first flagellomere.

Pronotum. Macrosculpture on lateral surface of pronotum present, dorsomedially foveate, laterally foveate-costate. Pubescence on lateral surface of pronotum present, sparse, composed of few short hairs. Anterior flange of pronotal plate distinctly protruding anteriorly, centrally smooth, longitudinally striate laterally. Carinae extending posteriorly from lateral margin of pronotal plate absent. Lateral pronotal carina present. Pronotal crest absent. Dorsal margin of pronotal plate (in anterior view) straight. Submedian pronotal depressions closed laterally, deep. Lateral margin of pronotal plate defined all the way to the dorsal margin of the pronotum. Pronotal plate wide, almost as wide as head.

Mesoscutum. Mesoscutal surface convex, evenly curved. Sculpture on mesoscutum present, foveate-punctate, with remnants of transverse costae. Notaulus present, marked by series of deep subcontiguous pits of uniform width. Median mesoscutal carina absent. Anterior admedial lines present, with adjacent cuticular surface horizontally striate. Median mesoscutal impression present, long, reaching over 1/2 length of mesoscutum. Parascutal carina distinctly sinuate, posteriorly ending in posteroventrally directed projection.

Mesopleuron. Horizontally strigulate, with striae converging along posterior margin of sclerite. Subpleuron entirely smooth with few long white setae anteriorly, posteriorly. Lower mesopleuron micro-pitted anteriorly, smooth and glabrous posteriorly. Epicnemial carina present, running from mesoscutum to anterior margin of mesopleural carina, narrow ventrally, costate. Lateroventral mesopleural carina present, not marking abrupt change of slope of mesopectus. Mesopleural triangle absent. Subalar pit large and well defined, lying in posterior end of subalar groove. Speculum present, microcarinate. Mesopleural carina present, complete, composed of several long, parallel, straight carinae. Anterior end of mesopleural carina inserting above notch in anterior margin of mesopleuron.

Scutellum. Dorsal surface of scutellum foveate-areolate. Circumscutellar carina absent. Posterior margin of axillula marked by distinct ledge, axillula distinctly impressed adjacent to ledge. Lateroventral margin of scutellum posterior to auricula smooth ventrally, obliquely longtidinally striate dorsally, entirely striate posteriorly. Dorsoposterior part of scutellum produced posteriorly into sharp spine, less than 1.0 × length of petiole. Dorsal part of scutellum entirely rugose. Scutellar plate absent. Scutellar foveae present, three, with lateral foveal bissected by longitudinal carina, resulting in five longitudi nally elongate subfovea. Longitudinal scutellar carinae absent. Single longitudinal carina separating scutellar foveae absent. Posterolateral margin of scutellum drawn out into distinct protuberance. Lateral Lateral bar narrow, with strong strigate, foveate sculpture.

Metapectal-propodeal complex. Metapectal cavity anterodorsal to metacoxal base present, ill-defined. Anterior margin of metapectal-propodeal complex separated from mesopleuron by deep, broad, uninterrupted marginal impression. Posteroventral corner of metapleuron (in lateral view) rounded, not drawn out posteriorly. Anterior i mpression of metepimeron present, narrow, linear impression, not broadened ventrally. Posterior margin of metepimeron distinct, separating metepimeron from propodeum. Subalar area slightly broadened anteriorly, without longitudinal division indicated. Calyptra present, blunt, lobe-like, polished posteriorly with setiferous punctures anteriorly. Dorsellum present with two strong medial fovea, glabrous. Anterior impression of metepisternum, immediately beneath anterior end of metapleural carina, large and wide. Pubescence consisting of few scattered hairs on posterior part of metapleuron and lateral part of propodeum. Propodeal spurs present, crenulate. Lateral propodeal carinae present, not reaching scutellum. Ventral end of lateral propodeal carina reaching nucha, carinae separated from each other. Inter propodeal carinae space glabrous with bifurcating central carina, foveate. Petiolar foramen removed from metacoxae, directed posteriorly. Horizontal carina running anteriorly from lateral propodeal carina present. Lateral propodeal carina uniformly curved inward. Calyptra, in lateral view, elongate. Propodeum relatively short, not drawn out posteriorly. Calyptra, in posterior view, rounded.

Legs. Pubescence posterolaterally on metacoxa sparse to moderately dense, confined dense hair patch absent. Microsculpture on hind coxa absent. Longitudinal carina on the posterior surface of metatibia absent. Metafemoral spine present, elongate, extending distally as low keel along ventral femoral margin. Distal mesotibial spurs shorter than medial spurs. Distal metatibial spurs equal in length to medial spurs. Ratio of first metatibial segment to remaining 4 segments less than 1.0. Pubescence on outer surface of metatarsal claw dense, consisting of numerous setae. Outer surface of metatarsal claw entirely smooth. Apical seta of metatarsal claw positioned on outer surface below dorsal margin. Base of metatarsal claw weakly expanded, apex slightly bent, ratio width of base to length of apex <0.6.

Forewing. Pubescence of forewing absent on basal half of wing, sparse distally. Apical margin of female forewing rounded. Rs+M of forewing tubular. Mesal end of Rs+M vein situated closer to posterior margin of forewing, directed towards posterior end of basalis. Vein R1 tubular along at least basal part of anterior margin of marginal cell. Basal abscissa of R1 (the abscissa between 2r and the forewing margin) of forewing as broad as adjacent wing veins. Coloration of forewing hyaline with slight infuscation covering marginal cell, area posterior to marginal cell. Marginal cell of forewing membranous, similar to other wing cells. Areolet absent. Hair fringe along apical margin of forewing absent.

Petiole. Distinctly elongate,>5 –6× longer than broad. Surface of petiole longitudinally costate, ventral keel absent.

Metasoma. Setal band (hairy ring) at base of tergum 3 absent, base of metasoma glabrous. Tergum 3 distinctly smaller than tergum 4. Posterior margin of tergum 3 smoothly rounded. Posterior margin of tergum 4 arcuate. In lateral view, sternum 3 exposed, ventral border of T2-T7 visible. Sculpture on metasomal terga present, finely punctate laterally, dorsally; posteriorly with large setal pits. Syntergum absent, all postpetiolar terga free. Annulus absent. Peg-like setae on T6-T7 absent.

Diagnosis.

The petiole on this species is unusually long, about 3x longer than its width; other species of Oberthuerella have petioles 2 × longer than wide, or less. In addition, Oberthuerella transiens has light and dark patches on the forewing, rather than entirely infuscate or entirely hyaline as in other species.

Distribution.

Democratic Republic of Congo. Link to Distribution Map. [http://hol.osu.edu/map-full.html?id=181562]

Material examined.

Holotype, male, Tessmannella transiens : DEMOCRATIC REPUBLIC OF THE CONGO: Kalemie (Albertville), 1.I-20.I.1919, R. Mayné, Mus. Cong. Cyn1-1 (deposited in MRAC).