Perissosega sulcata, Mita, 2022

Mita, Toshiharu, 2022, Taxonomy of Perissosega Krombein (Hymenoptera: Chrysididae, Amiseginae) with description of a new species from Japan, Zootaxa 5169 (3), pp. 279-285 : 283-284

Perissosega sulcata , new species ( Figs 11–17 )

Diagnosis. Body 2.1–2.3 mm; black, legs partly testaceous; fore wing strongly infuscate around 2r-rs 2 v; head punctate, punctures almost contiguous on vertex; scapal basin with dorsal margin not carinate; occipital carina present only posterior to ocellar region; ocelli forming regular triangle; mesosoma densely punctate; dorsal part of mesopleuron densely punctate and rugose; posterolateral corner of metapectal-propodeal complex angulate, forming a blunt posterior propodeal projection; distal part of pterostigma + R1 2 v 0.4 × 2r-rs 2 v; 2r-rs 2 v weakly curving; Rs&M 2 v arising almost at Cu-a 2 v; metasoma densely punctate, punctures shallow, somewhat smaller and sparser than those on mesosoma; median polished line present from T1 to T2. Male unknown.

This new species is distinguished from P. venablei by the shallow scapal basin without a strong dorsal carina (scapal basin is deep and the dorsal margin is surrounded by a strong transverse carina in P. venablei ); the incomplete occipital carina only present posterior to ocellar region (laterally complete, only absent or effaced posterior to ocellar region); the blunt posterior propodeal projection on the metapectal-propodeal complex (a long spine-like projection is present); the median smooth line on T1 (smooth line absent on T1).

Description. Holotype female. Body length 2.05 mm. Head ( Figs 12, 14, 15 ) punctate except scapal basin, 1.6 × as wide as long in dorsal view, as wide as deep in frontal view; punctures 0.3–0.6 × MOD, 0.2–0.5 × PD apart with smooth interspaces, denser and contiguous on vertex; scapal basin ( Fig. 14 ) shallow, cross-ridged with smooth median line; strong carina absent around dorsal margin; frons dorsally converging, shortest distance between eyes 0.33 × head width; MS 0.36 × maximum length of eye; lateral ocelli almost touching eye, OL 1.0, OPL 2.1, POL 1.0, OOL 0.1, MOD 0.6; occipital carina present only posterior to ocellar triangle; posterior margin of vertex excavated. Mandible cylindrical. Eye setose. Antenna compact, F2–F8 wider than long; length (width) of F1–F4 following ratio: 6.0 (2.0): 1.5 (2.5): 2.0 (3.0): 2.0 (3.0).

Mesosoma ( Fig. 16 ) covered with short decumbent setae. Pronotum punctate with smooth interspaces; punctures somewhat longitudinally contiguous, as large as those on frons, 0.3–1.0 × PD apart, sparser posteriorly; medial longitudinal line reaching 0.8 × length of pronotum; median length of pronotum 0.62 × longer than wide. Mesoscutum as long as pronotum, punctate with smooth interspaces; punctures smaller and denser on median part, larger and sparser on lateral part. Mesoscutellum 0.6 × mesoscutum, sculptured as median part of mesoscutum. Mesopleuron punctate with smooth interspaces; punctures 0.5 MOD, 0.2–0.6 × PD apart; dorsal part densely punctate and rugose. Metanotum with median triangular enclosure, median length 0.54 × mesoscutellum, densely punctate. Metapectalpropodeal complex rugose, with blunt posterior propodeal projection; dorsal surface slightly shorter than propodeal declivity, with median longitudinal carina; propodeal declivity weakly rugose, with median, sublateral and lateral carina. Fore wing tinged with brown, around 2r-rs 2 v more strongly infuscate ( Fig. 13 ).

Metasoma ( Fig. 14 ) punctate with smooth interspaces, surface covered with short decumbent setae; punctures on T1 somewhat longitudinally contiguous, ca. 0.3 × MOD, 0.2–1.0 × PD apart, denser posteriorly, punctures on T2 as large as T1, anteriorly denser, posteriorly sparser; median smooth line with one fine groove present on T1 and T2.

Color. Body black except mandible, antenna and tegula dark brown, joints of legs, protibia and tarsi testaceous, other part of legs dark brown, basal part of metasoma brownish.

Specimens examined. Holotype ♀, “JPN: Okinawa Pref., Iriomote-jima Isl., Haiminaka , yellow pan trap, 24.2897N, 123.8775E, 20m alt., 28-VIII-2020, T. Mita leg.” ( ELKU) . Paratype 1♀, same island as holotype, but Komi, Airagawa, 24.3261N, 123.8914E, 15. V . 2014, H. Handa leg. ( ELKU) .

Host. Unknown.

Etymology. The specific epithet sulcata, a Latin adjective, meaning bearing a groove. The species name refers to the median groove on metasoma.

Remarks. The paratype female shows the following variation: body length 2.25 mm; punctures on metasoma slightly denser.

Figures

FIGURE 11. Perissosega sulcata sp. nov., holotype ♀, lateral habitus. Scale bar = 1.0 mm.

FIGURES 12–17. Perissosega sulcata sp. nov., paratype ♀. 12, Head, dorsal view; 13, forewing; 14, head, frontal view; 15, head, lateral view; 16, mesosoma; 17, metasoma. Scale bars = 0.5 mm.