Oxyscelio gressus Burks

Burks, Roger A., Masner, Lubomir, Johnson, Norman F. & Austin, Andrew D., 2013, Systematics of the parasitic wasp genus Oxyscelio Kieffer (Hymenoptera, Platygastridae s. l.), part II: the Australian and southwest Pacific fauna, ZooKeys 331, pp. 1-266 : 92-94

Oxyscelio gressus Burks sp. n. Figures 127-132; Morphbank52

Description.

Female. Body length 3.55-3.7 mm (n=2).

Radicle color and shade: darker than scape. Pedicel color: same as scape. A3: shorter than pedicel; as long as pedicel. A4: broader than long. A5: broader than long.

Ventral clypeal margin: with slightly convex median lobe. Interantennal process: not elongate. Lower frons at dorsal margin of interantennal process: without transverse carina. Transverse curved rugae extending from frontal depression to eye: absent. Median longitudinal carina in frontal depression: absent. Ventral portion of frontal depression: with medially interrupted transverse carinae; smooth. Dorsal portion of frontal depression: with medially interrupted transverse carinae. Submedian carina: present. Frontal depression dorsally: not hood-like, open dorsally. Upper frons major sculpture: umbilicate foveate; irregularly rugose. Upper frons microsculpture: absent. Hyperoccipital carina: indicated by a set of irregular elevations. Carina connecting occipital carina to hyperoccipital carina: absent. Occipital carina: weakly arched dorsally, with rounded lateral corners. Occiput sculpture: transversely rugose. Extra carina ventral to occipital carina: present, complete. Gena length: shorter than eye. Major sculpture of gena anteroventrally: umbilicate foveate. Major sculpture of gena posteroventrally: rugose. Microsculpture of gena anteroventrally: absent. Microsculpture of gena posteroventrally: granulate.

Lateral pronotal area sculpture: anteriorly smooth, posterodorsal corner with dense microsculpture, ventral corner with irregular carinae. Posterior border of central pronotal area: directed anteriorly, protruding at corner of epomial carina and transverse pronotal carina. Mesoscutum anteriorly: very steep and tall, descending at a right angle or protruding anteriorly. Major sculpture of mesoscutal midlobe anteriorly: umbilicate foveate. Mesoscutal midlobe sculpture at midlength: with large smooth areas. Major sculpture of mesoscutal midlobe posteriorly: umbilicate foveate; irregularly rugose. Microsculpture of mesoscutal midlobe anteriorly: granulate. Microsculpture of mesoscutal midlobe posteriorly: absent. Median mesoscutal carina: present as a narrow carina. Major sculpture of mesoscutellum centrally: umbilicate foveate. Major sculpture of mesoscutellum peripherally: umbilicate foveate. Microsculpture of mesoscutellum centrally: absent. Microsculpture of mesoscutellum peripherally: absent. Mesoscutellar rim: not expanded. Mesoscutellar rim medially: without notch. Mesofemoral depression: longitudinally striate dorsally, smooth ventrally. Metascutellum shape: deeply emarginate, with the resulting pair of posterior processes subtriangular and directed dorsally. Metascutellar setae: absent. Metascutellum sculpture: with large smooth posterior fovea. Postmarginal vein: absent. Fore wing apex at rest: reaching middle of T5. Coxae color brightness: same color as femora. Spines along tibiae: absent. Lateral propodeal carinae: broadly separated, not parallel anteriorly. Setae in metasomal depres sion: present. Anterior sculpture of metasomal depression: absent. Median propodeal carina: absent.

T1 horn: absent. Number of longitudinal carinae of T1 midlobe: 5. T1 lateral carina: protruding laterally, visible from ventral view. T2 sculpture: with longitudinal striae or rugae, setiferous puncta present between them. T2 sublateral longitudinal foveae: absent. T3 metasomal flanges: absent. T4 sculpture: longitudinally striate to rugose, setal pits spanning interspaces. T4 metasomal flanges: present as slightly protruding sharp corners. T5 sculpture: longitudinally striate to rugose, setal pits spanning interspaces. T5 metasomal flanges: present as slightly protruding sharp corners. T6: broader than long. Major sculpture of T6: umbilicate punctate. Microsculpture of T6: absent. T6 medially: with a median projection set off by an abrupt narrowing posterior to tiny metasomal flanges, not separated from apical rim. T6 metasomal flanges: present subapically. T6 raised peripheral rim: absent. S4 sculpture: longitudinally striate or rugose, setal pits spanning interspaces. S5 sculpture: longitudinally striate to rugose, setal pits spanning interspaces. S5 median carina: present. S6 peripheral carina: absent. S6 apex in relation to T6: not exposed to dorsal view. S6 apex: rounded or acuminate.

Male. Body length 3.65-3.75 mm (n=2). A3: longer than pedicel. A5 tyloid shape: narrow, linear. A6: broader than long. A11: broader than long. Major sculpture of mesoscutal midlobe anteriorly: umbilicate foveate. Major sculpture of mesoscutal midlobe posteriorly: umbilicate foveate. Microsculpture of mesoscutal midlobe anteriorly: granulate. Microsculpture of mesoscutal midlobe posteriorly: absent. Major sculpture of mesoscutellum centrally: umbilicate foveate. Major sculpture of mesoscutellum peripherally: umbilicate foveate. Microsculpture of mesoscutellum centrally: absent. Microsculpture of mesoscutellum peripherally: absent. Fore wing apex at rest: reaching middle of T6. T1 midlobe longitudinal carinae: 4. T3 metasomal flanges: absent. T4 metasomal flanges: absent. T5 metasomal flanges: absent. T6 metasomal flanges: absent. T7: broadly and deeply emarginate, with rounded posterolateral margins.

Diagnosis.

Both sexes: Frontal depression deep; submedian carina distinct, sharp. Hyperoccipital carina indicated by rugae. Occipital carina complete, medially convex. Metascutellum concave dorsally, weakly emarginate apically, projecting dorsally. Coxa same color as most of femur, leg otherwise lighter in color. Postmarginal vein absent. Female: A3 not longer than pedicel. A4, A5 broader than long. Fore wing long enough to reach middle of T5. T1 midlobe with 5 longitudinal carinae. T4 with sharp corners, T5 with small sharp metasomal flanges, not otherwise abruptly narrower than preceding tergum. Main body of T6 not raised above apical rim, not abruptly separated from it; T6 with small and sharp subapical metasomal flanges. S6 not exposed to dorsal view. Male: A4, A11 broader than long. Fore wing long enough to reach middle of T6. T7 deeply emarginate, with broad posterolateral lobes. Oxyscelio gressus is very similar to Oxyscelio cuspidis , but females differ in having a shorter A3 and 4 T1 midlobe longitudinal carinae instead of 5. In Oxyscelio cuspidis , A3 is much longer than the pedicel, while in Oxyscelio gressus it is about the same length.

Etymology.

Latin 4th declension noun, genitive case, meaning "a step."

Link to distribution map.

[http://hol.osu.edu/map-full.html?id=307081]

Material examined.

Holotype, female: AUSTRALIA: WA, 40km SE Armadale, Banksia-jarrah forest, Mount Cooke, 7.XII-22.XII.1990, malaise trap, A. D. Austin, OSUC 456176 (deposited in WAMP). Paratypes: AUSTRALIA: 1 female, 2 males, OSUC 456177-456179 (WINC).