Seneciobracon novalatus Engel & Huang

Engel, Michael S., Huang, Diying, Cai, Chenyang & Alqarni, Abdulaziz S., 2018, A new lineage of braconid wasps in Burmese Cenomanian amber (Hymenoptera, Braconidae), ZooKeys 730, pp. 73-84 : 76-78

Seneciobracon novalatus Engel & Huang sp. n. Figs 1, 2

Holotype.

♀ (Fig. 1A), NIGP 164784, lowermost Cenomanian (near Albian boundary), Hukawng Valley, Kachin State, northern Myanmar; deposited in the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, China.

Diagnosis.

As for the subfamily (vide supra).

Description.

♀: Total length 2.0 mm (as preserved, excluding ovipositor); forewing length 1.50 mm, hind wing length 1.35 mm; integument dark brown (Fig. 1A), lighter on mouthparts, tarsi, ovipositor, and ovipositor sheaths; wing veins brown to dark brown, membranes hyaline.

Head apparently longer than broad (direct facial view not possible, observable in frontal-oblique view: Fig. 2a), impunctate and imbricate, with sparse, minute setae on face, such setae slightly longer on clypeus; face below antennal toruli faintly convex, sloping to distinct impression along epistomal sulcus; clypeus protruding, rounded, short, medial length about one-third that of length of face from antennal toruli to epistomal sulcus; hypoclypeal depression deep and wide; mandible short, just meeting opposing mandible when closed, apparently with a single, minute, subapical tooth; maxillary palpus elongate, longer than head, with 6 palpomeres, with palpomeres II–VI longer than wide, individual palpomeres with dense, minute setae; compound eye large and glabrous, length 0.28 mm, much broader than gena, inner margin not emarginate; ocelli positioned on top of vertex; ocelli well separated, median ocellus separated from lateral ocelli by approximately twice median ocellar diameter, lateral ocelli separated from posterior of head by almost twice median ocellar diameter, ocellocular distance slightly more than twice ocellar diameter; antenna slightly shorter than body length (excluding ovipositor); scape twice as long as apical width, length 0.08 mm, width 0.04 mm, truncate apically; pedicel about 1.75 times as long as wide, about as broad as scape, length 0.07 mm; flagellum with 19 flagellomeres; basal flagellomeres elongate and of approximately equivalent widths, flagellomere I length 0.15 mm, width 0.03 mm; flagellomere II length 0.12 mm; flagellomere III length 0.12 mm; remaining flagellomeres progressively tapering in length toward apex, apical flagellomeres about 2.0-2.25 times as long as wide except apicalmost flagellomere slightly more than 3 times as long as wide; multiporous plate sensilla sparse; apicalmost flagellomeres with a short, thick, peg-like seta at apex.

Mesosoma length 0.75 mm; pronotal collar distinct; pronotal surface smooth, dorsope and laterope absent; mesoscutum smooth, raised above pronotum; notauli deeply impressed, simple, percurrent but not meeting; lateral areas of mesoscutum (lateral to notauli) distinctly raised, convex; mesoscutellar sulcus deeply impressed, simple; mesoscutellum slightly raised, convex, smooth; mesopleuron smooth; propodeum areolate. Legs slender, with numerous setae; metafemur swollen; tibial spurs short, protibial calcar slightly curved, without comb; tibiae without spines or peg-like setae; metatibia length 0.63 mm; basitarsi largest tarsomeres, but shorter than combined length of remaining tarsomeres; pretarsal claws short, simple; arolium small. Forewing (Fig. 2B) with minute costal cell present apically near base with pterostigma, otherwise C+Sc+R fused along length; pterostigma large, longer than wide, with border inside marginal cell comparatively straight, anterior border convex, bulging; marginal cell large, extending nearly to wing apex, broad, broader than pterostigmal width; 1Rs exceedingly short, forming straight line with 1M; 1Rs+M originating near prestigma; 1M straight; 1Rs+M long, slightly curved, extending strongly posteriad to meet 1m-cu; 1m-cu meeting Rs+M near longitudinal tangent of M+Cu; 2Rs+M present, exceedingly short; first submarginal cell trapezoidal, but nearly triangular owing to short 2Rs+M; second submarginal cell large, nearly square, apical border formed of nebulous rs-m; r-rs arising slightly distad pterostigmal midlength, much shorter than 3Rs, at least 2 times longer than 1Rs; 1cu-a postfurcal; 1Cu shorter than 1cu-a; 2Cu much longer than 1Cu; 2cu-a absent, thus subdiscal cell open; stubs of 1a and 2a absent. Hind wing (Fig. 2C) with margins setose and secondary ‘hamuli’ (two distinctively elongate setae on anterior margin at apex of C); 3 distal hamuli present on R; R tubular on anterior wing margin for short distance, otherwise extending as nebulous vein to near wing apex; 2Sc+R distinct, longer than sc+r-m; sc+r-m without bulla; Rs tubular near base then extending as nebulous vein; 2M tubular near base then nebulous; 1Cu shorter than 1M; 2Cu absent; bulla present between apex of A and Cu.

Metasoma length 1.0 mm; terga with integument transversely wrinkled, otherwise impunctate, with sparse, minute setae; sterna apparently smooth and impunctate; tergum I about as long as wide, terga II and III apparently longer than wide, fused; remaining terga transverse; dorsope of tergum I apparently absent; ovipositor long, straight, shorter than metasoma when exerted, length 0.80 mm; ovipositor sheaths slightly broader apically, with abundant minute setae.

♂: Latet.

Etymology.

The specific epithet is a combination of the Latin novus, meaning, “new”, and alatus, meaning, “wing”, and is a reference to the more derived wing venation relative to other Cretaceous amber Braconidae (e.g., the protorhyssalines and Aenigmabracon Perrichot et al.).