Oberthuerella tibialis Kieffer

Buffington, Matthew L. & Noort, Simon van, 2012, Revision of the Afrotropical Oberthuerellinae (Cynipoidea, Liopteridae), ZooKeys 202, pp. 1-154 : 67-72

Oberthuerella tibialis Kieffer Figures 33-34

Oberthuerella tibialis Kieffer, 1904: 107

Description.

Coloration of head and mesosoma, black to dark brown; metasoma and legs yellow-orange. Sculpture on vertex, lateral surface of pronotum and mesoscutum present, deeply foveate laterally on head; pronotum, mesoscutum striate-foveate.

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 present, with distinct 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 present, punctate-rugose, transversely striate; striations meeting at medial 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, foveate. Malar sulcus absent. Compound eye close to posterior ocellus, ratio of distance between com pound 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. Maxillary palp composed of three segments. 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. Female antenna composed of 11 flagellomeres. Female F1 shorter than F2; black. Flagellomeres of female antenna cylindrical, not widened towards apex, non-clavate. Placoidal sensilla absent. Second flagellomere of male antenna cylindrical. Length of second flagellomere of male antenna longer than first flagellomere. Distal flagellomeres of female antenna not conspicuously enlarged compared to proximal flagellomeres.

Pronotum. Macrosculpture on lateral surface of pronotum present, dorsomedially with fine transverse reticulation, dorso-laterally foveate-punctate. Pubescence on lateral surface of pronotum absent. Anterior flange of pronotal plate distinctly protruding anteriorly, transversely striate. 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, flat, indistinct, with adjacent cuticular surface foveate. Median mesoscutal impression present, long, reaching over 1/2 length of mesoscutum. Parascutal carina distinctly sinuate, posteriorly ending in posteroventrally directed projection.

Mesopleuron. Dorsally irregularly horizontally costate with occasional fovea, ventrally smooth. Subpleuron entirely smooth, glabrous. Lower mesopleuron micro-pitted anteriorly, smooth and glabrous posteriorly. Epicnemial carina present, running from mesoscutum to anterior margin of mesopleural carina, spread out ventrally, shagreened. Lateroventral mesopleural carina present, 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, smooth to micro-pitted. Mesopleural carina present, complete, composed of several long, irregular, curved 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, becoming dorsoventrally 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, two, each with two longitudinal divisions resulting in transverse row of 6 longitudinally elongate subfovea. Longitudinal scutellar carinae absent. Single longitudinal carina separating scutellar foveae present, short, ending at posterior margin of foveae. Posterolateral margin of scutellum drawn out into distinct protuberance. 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 impression of metepimeron present, narrow, linear impression, not broadened ventrally. Posterior margin of metepimeron distinct, separating metepimeron from propodeum. Subalar area slightly broadened anteriorly, with distinct laterally protruding lobe ventrally. 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, present, small and narrow. Pubescence thin, evenly covering entire metapectal-propodeal complex. Propodeal spurs present, foveate. Lateral propodeal carinae present, not reaching scutellum. Ventral end of lateral propodeal carina terminating before reaching nucha. Inter propodeal carinae space lightly setose, horizontally striate. Petiolar foramen removed from metacoxae, directed posteriorly. Horizontal carina running anteriorly from lateral propodeal carina present. Lateral propodeal carina straight, sub-parallel. Calyptra, in lateral view, elongate. Propodeum relatively short, not drawn out posteriorly. Calyptra, in posterior view, dorsoventrally elongate.

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 equal in length to medial spurs. Distal metatibial spurs equal in length to medial spurs. Ratio of first metatibial segment to remaining 4 segments equal to 1.0. Pubescence on outer surface of metatarsal claw sparse, consisting of few setae. Outer surface of metatarsal claw microcarinate. 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. Forewing entirely lightly infuscate. Marginal cell of forewing membranous, similar to other wing cells. Areolet absent. Hair fringe along apical margin of forewing absent.

Petiole. Slightly elongate, 1.5 –2× longer than wide. Surface of petiole longitudinally costate, ventral keel absent. Posterior part of female petiole not abruptly widened. Ventral flange of annulus of female petiole 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, dorsally with broad setal pits, ventrally with dense, fine punctation. Syntergum absent, all postpetiolar terga free. Annulus absent. Peg-like setae on T6-T7 absent. Posteroventral cavities of female metasoma T7 present, glabrous save for few, long setae. Female posteroventral margin of T6-T7 gently sinuate. Terebrum and hypopygium (in lateral view) straight, pointing posteriorly.

Ovipositor. First valvula of ovipositor narrowing gradually, not broadened apically, serrate at tip. Ovipositor clip absent.

Diagnosis.

This species is most easily confused with Oberthuerella pardolatus , but can seperated from that species by: 5 subfovea present at base of scutellum (7 in Oberthuerella pardolatus ); admedial lines indistinct (distinct in Oberthuerella pardolatus ); mesoscutum dominated by very shallow fovea (deep and distinct in Oberthuerella pardolatus ).

Distribution.

Cameroon, South Africa; Zimbabwe. Link to Distribution Map. [http://hol.osu.edu/map-full.html?id=181561]

Material examined.

Holotype, female: CAMEROON: no date, Sjostedt, USNM ENT 00764779 (deposited in NHRS). Other material: (2 females, 1 male) SOUTH AFRICA: KwaZulu-Natal Prov., Sodwana Nature Reserve, 11.XI.1984, H. Howden (1 female, USNM ENT 00764777 (CNCI)). Transvaal, no date, Junod (1 male, USNM ENT 00764778 (MHNG)). ZIMBABWE: Harare (Salisbury), 21.I.1915 (1 female, SAM-HYM-P003004 (SAMC)).