Pison metallescens Pulawski, 2018

Pulawski, Wojciech J., 2018, A Revision of the Wasp Genus Pison Jurine, 1808 of Australia and New Zealand, New Guinea, and the Pacific Islands (Hymenoptera: Crabronidae), Proceedings of the California Academy of Sciences 65, pp. 1-584 : 511-514

Pison metallescens Pulawski , species nova

Figures 1229-1236.

NAME DERIVATION.– Metallescens is a Neolatin word meaning with metallic shine; with reference to this species head, thorax, and propodeum color.

RECOGNITION.– Among the New Guinean Pison , the three species with only two submarginal cells are P. aberrans , P. difficile , and P. metallescens . They differ by a number of characters indicated in the key. Pison metallescens differs from all the Australian and New Guinean species with only two submarginal cells in having terga I and II practically impunctate (Fig. 1235) rather than densely punctate, and also in having the head, thorax, and propodeum with an inconspicuous bluish lustre (rather than all black). Subsidiary recognition features are: the gaster sessile (the length of tergum I is smaller than its apical width), the posterior margin of the second submarginal cell equal to 2.1 × its height (Fig. 1234), the tegula largely impunctate posteriorly, the mesopleuron sparsely punctate, the posteroventral surface of the forefemur impunctate, the propodeal dorsum finely punctae (Fig. 1233), and the posterior propodeal surface unridged, with well-defined punctures.

DESCRIPTION.– Frons aciculate but not totally dull, finely punctate, punctures on upper frons averaging about 2-3 diameters apart (Fig. 1230), middle supraantennal carina rudimentary. Occipital carina slightly expanded ventrally. Labrum emarginate. Gena narrow in dorsal view (Fig. 1231). Anteromedian pronotal pit transversely elongate, about 3 × as long as midocellar diameter. Scutum not foveate along flange, without short longitudinal ridges adjacent to posterior margin; scutal punctures fine, averaging about one diameter apart (Fig. 1232). Tegula somewhat expand- ed, fully covering humeral plate. Mesopleural punctures fine, several diameters apart except near borders. Postspiracular carina ill defined. Metapleural sulcus not costulate between dorsal and ventral metapleural pits. Propodeum with longitudinal carina separating side from dorsum and posterior surface and extending from gastral socket area toward spiracle; dorsum finely punctate (punctures several diametes apart) and also with ill-defined, transverse ridges that are invisible from several angles (Fig. 1233); side unsculptured on disk, with several fine ridged anterodorsally; posterior surface unridged, with well-defined punctures. Forewing with two submarginal cells; posterior margin of second submarginal cell equal to 2.1 × its height (Fig. 1234). Posteroventral forefemoral surface and posterior surface of midfemur with only a few scattered punctures, practically impunctate. Outer surface of hindtibia with minute spines. Horizontal surface of tergum I with a few, sparse punctures (Fig. 1235); terga II and III with sparse punctures that are many diameters apart. Sternum II (except laterally) with a few, sparse punctures.

Setae silvery, on frons oriented uniformly dorsad, on postocellar area erect but shorter than midocellar diameter, appressed on scutum and tergum I, on lower gena suberect, shorter than midocellar diameter; not concealing integument on clypeus. Apical depressions of terga without setal fasciae.

Head, thorax, propodeum and gaster black with inconspicuous bluish lustre except mandible and flagellar venter ferrugineous (mandible black basally, brown apically; flagellum all black apically). Wing membrane yellowish, veins in basal half pale yellow. Femora black; foretibia black, ferruginous on inner surface and on apical third, midtibia black, ferruginous on anterior surface, hindtibia black, partly ferruginous on posterior (= inner) surface; tarsi ferruginous.

♀.– Upper interocular distance equal to 0.96 × lower interocular distance; ocellocular distance equal to 1.2 × hindocellar diameter, distance between hindocelli equal to 1.0 × hindocellar diameter; eye height equal to 1.10 × distance between eye notches. Free margin of clypeal lamella subrectangular (Fig. 1229). Dorsal length of flagellomere I 1.5 × apical width, of flagellomere IX

1.1 × apical width. Mandible: trimmal carina without small incision. Tergum VI with median carina at very apex. Length 7.3 mm; head width 1.8 mm.

♂.– Unknown.

GEOGRAPHIC DISTRIBUTION (Fig. 1236).– Known from a single locality in Papua New Guinea mountains.

RECORDS.– HOLOTYPE: ♀, PAPUA NEW GUINEA: Madang Province: Pandambai 6 air km W Bundi at 5º38ʹS 145º11ʹE, alt. 2,330 m, 10-13 May 1888, W.J. Pulawski ( CAS).