Austrostelis bicolor Griswold, 2025

Austrostelis bicolor Griswold , new species

ZooBank: urn:lsid:zoobank.org:act:

( Figs. 1, 2 View Figures 1–5 , 6, 7 View Figures 6–10 , 11, 12 View Figures 11–15 , 16, 17, 21)

DIAGNOSIS: This species differs from other northern species by the more angulate axillae ( Figs. 11, 12 View Figures 11–15 ), short labrum, T2 with coarser punctation and broader impunctate margin (Figs. 16, 17), and absence of submedial, longitudinal stripes on the scutum ( Figs. 11, 12 View Figures 11–15 ). From the potentially co-occurring A. flava (Friese) it differs in tergal punctation finer and impunctate tergal margins narrower.

DESCRIPTION: Female. Body length, 5.6 mm; intertegular distance, 1.58 mm. Body with black marks limited to head and mesosoma, metasoma dorsally orange with yellow markings ( Fig. 1 View Figures 1–5 ). Forewing smoky apically including marginal cell, stigma and veins surrounding marginal cell dark brown ( Fig. 1 View Figures 1–5 ). Labrum short, not reaching full length of fossa, mouthparts in repose exposed apically. Mandible 4-toothed, third tooth weak, obtuse, gap dorsal to it deeper than one ventral to it. Clypeus with moderate, nearly contiguous punctures. Subantennal suture convex ( Fig. 6 View Figures 6–10 ). Juxtantennal carinae with even flare. Flagellum dark except F1, F2 yellow; penultimate segment slightly longer than broad. Pronotal collar lacking narrow groove laterally. Scutum polished; punctation dense, not contiguous; punctures regular ( Fig. 11 View Figures 11–15 ). Scutellum with apical margin very broadly, evenly convex, carinate except medially; laterally, at margin with axilla, exceeding the axillar length. Axilla angulate laterally ( Fig. 11 View Figures 11–15 ). Mesepisternum with punctation dense, punctures medially no larger than those on scutum laterally. Metapleuron with puncture row along anterior margin, disc without punctures on ventral half, posterior margin distinctly angulate near middle. Forewing unicolored, venation dark; marginal cell darkly cloudy in contrast to surrounding areas ( Fig. 1 View Figures 1–5 ). T2 with lateral margin in dorsal view slightly convex; punctation of subapical band slightly smaller than on disc, not fine; apical impunctate margin moderately wide (Fig. 16). T3–T6 with rather dense, subappressed white pubescence. T6 with small preapical pit medially, with very fine indistinct transverse preapical striae.

Male. Body length, 5.3 mm; intertegular distance, 1.52 mm. As female except: Mandible apically reduced, 3-toothed. Labrum with apical margin truncate, not angled medially. Additional flagellomere. T2 shape as in female but punctation medially less dense, less coarsely punctate, only slightly finer than on disc (Fig. 17). T7 apical margin slightly convex with hint of emargination medially. S2 short, disc flat, apical zone translucent, concolorous ( Fig. 21 View Figures 21, 22 ). S3 apical margin slightly incurved on middle two-thirds, laterally slightly angled anteriorly, fringe on margin dense, straight medially becoming long laterally, curled toward midline. S4, S5 with similarly configured fringes but shorter. S5, S6 with small apicolateral slightly acute angle

TYPE MATERIAL: Holotype female: “ Venezuela Merida Los Araques 13km W Lagunillas 18-VII-1991 L.Stange & C.Porter ” ( HOLO103 ) . Paratypes: same data, 1 female, 7 males . Holotype deposited in FSDA , paratypes in FSDA and BBSL .

COMMENTS: This is the first record of Austrostelis from Venezuela. It runs to couplet 5, A. flava , in Parizotto et al. (2018) but differs as indicated in the diagnosis. It is worth noting that both species from northern South America, this species and A. flava from Colombia, have a pale metasoma unlike the largely dark metasomal coloration in all known species from more southerly parts of South America. A single male from the type locality has the basal zone of T2 black. This specimen is also larger than the other specimens and may not be conspecific, so is not included here. The markings, body size and shape of A. bicolor are virtually identical with Hypanthidium magdalenae Urban of adjacent northern Colombia.