Pison minutum 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 : 279

Pison minutum Pulawski , species nova

Figures 645 -649.

NAME DERIVATION.– Minutus (neuter: minutum ), a Latin adjective meaning minute; with reference to this species body size.

RECOGNITION.– Only the female of this species is known. It is small (length 3.8-4.0 mm), all black, with three submarginal cells, the second recurrent vein interstitial with the second intersubmarginal vein, and the setae appressed on tergum I. It has a psammophore on the forefemoral venter and in some specimens also on the lower gena, but unlike other such species the psammophore is unusually short, its longest setae being equal to 0.5-0.6 × midocellar diameter; the lower gena is impunctate and asetose on each side of the oral fossa. The scutum conspicuously microsculptured between punctures, the absence of the median sulcus on the propodeal dorsum, the absence of the longitudinal carina separating the propodeal side from the dorsum and posterior surface, and the sterna punctate throughout are subsidiary recognition features.

DESCRIPTION.– Frons dull, minutely punctate, punctures less than one diameter apart, middle supraantennal carina absent. Gena narrow in dorsal view ( Fig. 646 ). Labrum not emarginate. Anteromedian pronotal pit transversely elongate, about two thirds of the midocellar diameter. Propleuron impunctate anteriorly, conspicuously microsculptured. Scutum not foveate along flange, without longitudinal ridges adjacent to posterior margin; scutal punctures fine, less than one diameter apart ( Fig. 648 ); interspaces dull, markedly microsculptured. Tegula not enlarged. Mesopleural punctures minute, less than one diameter apart, partly concealed by appressed setae. Postspiracular carina absent. Metapleural sulcus costulate between dorsal and ventral metapleural pits. Propodeum without longitudinal carina separating side from dorsum and posterior surface and extending from gastral socket area toward spiracle; dorsum irregularly, longitudinally ridged, punctate between ridges, without middle sulcus; side ridged, punctate between ridges, ridges oriented longitudinally except anterior ridges oriented anteroventrally; posterior surface irregularly transversely ridged, punctate between ridges. Hindcoxal dorsum with outer margin obtusely carinate. Outer surface of hindtibia with evanescent spines. Punctures of tergum I minute, about one diameter apart anterior to apical depression. Sterna finely, closely punctate throughout.

Setae silvery, appressed on upper frons, postocellar area, scutum, and tergum I, oriented ventrally on upper frons; not concealing integument on clypeus; genal setae: see below. Apical depressions of terga with silvery, setal fasciae.

Body all black, mandible (except basally) and tarsi dark brown.

♀.– Upper interocular distance equal to 0.60 × lower interocular distance; ocellocular distance equal to 0.5 × hindocellar diameter, distance between hindocelli equal to 1.0 × hindocellar diameter; eye height equal to 0.88 × distance between eye notches. Free margin of clypeal lamella arcuate, with ill-defined lateral corner ( Fig. 645 ). Dorsal length of flagellomere I 2.0 × apical width, of flagellomere IX 1.1 × apical width. Lower gena impunctate and asetose on each side of oral fossa. Mandibular posterior margin and forefemoral venter with psammophore, psammophore absent on lower gena in paratype ( Fig. 647 ), in holotype present on right side and absent on left side (psammophore short, its longest setae about 0.5-0.6 × midocellar diameter). Mandible: trimmal carina with minute incision at about two thirds of length. Tergum VI somewhat broadened. Length 3.8-4.0 mm; head width 1.3 mm.

♂.– Unknown.

Figures

FIGURES 645-648. Pison minutum Pulawski, sp. nov., female. (645) Clypeus and mandibles; (646) Head in dorsal view; (647) Left gena in lateral view; (648) Tegula an adja- cent scutum. FIGURE 649. Collecting locality of Pison minutum Pulawski, sp. nov.