Bracalba tricorata Burks

Burks, Roger A., Masner, Lubomir, Johnson, Norman F. & Austin, Andrew D., 2012, Taxonomic revision of Bracalba Dodd (Hymenoptera, Platygastridae s. l.), a parasitoid wasp genus endemic to Australia, ZooKeys 236, pp. 1-53 : 36-38

Bracalba tricorata Burks sp. n. Figures 60-61Morphbank29

Description.

Female. Body length 3.88-4.25 mm (n=4). Color of antenna beyond radicle: entirely dark. Radicle color: same as scape. Number of claval segments with ventral gustatory sensilla: 7. Number of ventral gustatory sensilla on A6: 1.

Ocular setae: short and sparse. Frontal depression: with many strong transverse carinae, sparsely foveolate at torular triangle. Smooth depression extending dorsolaterally from antennal foramen: present. Dorsal clypeal margin: bordering antennal foramina, absent between them. Clypeal median carina: absent. Ventral clypeal margin: with a small median point. Mandibular color: mostly yellowish brown, dark at teeth. Mandibular teeth: three, but middle tooth tiny. Smooth area obliquely posterior to la teral ocellus: present. Genal sculpture: deeply reticulate-rugose with some septa much stronger than others, forming distinct rows differing in height.

Dorsal pronotal area: not set off by carina ventrally. Anterolateral corner of dorsal pronotal area: weakly rounded anteriorly. Sculpture of posteromedian area of mesoscutum: foveolate with slightly stronger longitudinal septa. Lateral margin of dorsal axillar area: with a semicircular expansion, broadest near midlength. Mesoscutellar sculpture: sparsely foveolate, with large smooth interspaces. Metascutellum in dorsal view: trapezoidal with broad apex. Dorsal surface of metascutellum: convex. Femoral depression: crossed by rounded carinae. Leg color: coxae, femora (aside from their apices), and at least the last two tarsomeres dark, otherwise yellowish brown. Anterior corner of lateral propodeal carina: flat, without tooth. Posteromedial corner of lateral propodeal area: protruding posteriorly.

Metasoma color: black to dark reddish brown. Median lobe of T1: with a set of rugae that merge with one another. Metasoma at middle of T4: with very weak bend. Posterolateral margins of metasomal terga: without protrusions. T5 median carina: absent. Longitudinal sculptural septa on T5: weak, blunt and hardly raised. Transverse sculptural septa on T5: about as strong as the longitudinal septa. T5 setae: directed posteriorly, arising from anterior edge of sculptural mesh. T6: as broad or broader than long. T6 laterotergite: overlapped by rim from S6. S4 median carina: absent. Transverse sculptural septa on S5: weak or absent, much weaker than the longitudinal septa. S5 setae: directed posteriorly, arising from anterior edge of sculptural mesh. Lateral carinae of S6: forming complete peripheral carina. Apex of S6: without notch.

Male. Body length 3.75-4.00 mm (n=3). Flagellomere length: A3 over 1.5 × as long as broad, most others as long or longer than broad. T7: arched and posteriorly concave.

Diagnosis.

Female. A6 with 1 large ventral sensillum; 3 mandibular teeth with the middle tooth much smaller than the others; metascutellum broadly trapezoidal with a broad apex that is truncate or sometimes slightly incised; metasomal bend present but very weak; sculpture posterior to metasomal bend with transverse septa about as strong as the longitudinal septa; T4-T6 without median carina, S4-S6 with or without median carina; T6 about as broad as long; S5 with longitudinal septa much stronger than transverse septa; S6 without apical notch. This species is very similar to Bracalba pinnula , but has distinctly different ventral metasomal sculpture.

Etymology.

Latin participle meaning “tricky,” named for its strong similarity to some other species and its very subtle metasomal bend.

Link to distribution map.

http://hol.osu.edu/map-full.html?id=302163

Material examined.

Holotype, female: AUSTRALIA: WA, 20km N Denmark, 16.I.1987, J. S. Noyes, OSUC 238541 (deposited in WAMP). Paratypes: AUSTRALIA: 3 females, 3 males, OSUC 148699, 238192, 238195, 238197, 238199-238200 (CNCI).