Pison modestum 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 : 280-282

Pison modestum Pulawski , species nova

Figures 650 -657.

NAME DERIVATION.– Modestus (neuter: modestum ) is the Latin adjective meaning modest; with reference to this species small size and lack on conspicuous diagnostic features.

RECOGNITION.– Pison modestum is an all black, small species (length 6.2-6.8 mm in female, 5.4-6.3 mm in male), with three submarginal cells, the second recurrent vein interstitial with second intersubmarginal vein, and setae appressed on the frons, postocellar area, scutum, and tergum I, on the lower gena curved, slightly shorter than the midocellar diameter. It is further characterized by the narrow ocellocular distance (equal to about 0.4 × postocellar diameter), the absence of the carina separating the propodeal side from the dorsal and posterior surfaces, and in the male the free margin of the clypeal lamella obtusely angulate to narrowly arcuate ( Fig. 651 ). Pison angustivertex a n d P. brachyceras are similar¸ but they differ in having the propodeal dorsum markedly ridged, with the punctures inconspicuous, and the entire posterior propodeal surface ridged (at least mesally). In P. modestum , the posterior propodeal surface is punctate in the dorsal half or so; the propodeal dorsum, in the female, is finely, obliquely ridged, the ridges not concealing the punctures, and in the male punctate, somewhat ridged adjacent to the anterior margin and next to the median sulcus (at least some punctures are more than one diameter apart except less than one diameter apart laterally).

DESCRIPTION.– Frons slightly swollen above antennal socket, minutely punctate, punctures ill defined, about one diameter apart, interspaces conspicuously microsculptured; middle supraantennal carina present, but short, about as long as 0.5 × midocellar diameter. Gena narrow in dorsal view. Labrum emarginate. Anteromedian pronotal pit transversely elongate, about as long as midocellar diameter. Scutum not foveate along flange, without longitudinal ridges adjacent to posterior margin; scutal punctures minute, about one diameter apart; interspaces markedly microsculptured. Tegula not enlarged. Mesopleural punctures fine, slightly more than one diameter apart; interspaces unsculptured. Postspiracular carina present, 1.0-1.5 × as long as midocellar diameter. Metapleural sulcus not costulate between dorsal and ventral metapleural pits. Propodeum adjacent to anterior margin and next to median sulcus ( Fig. 653 ), at least some punctures more than one diameter apart except laterally; side punctate (punctures averaging more than one diameter apart), interspaces in some specimens merging into minute ridges; posterior surface punctate, transversely ridged in ventral third or quarter. Posteroventral forefemoral surface microscopically, closely punctate. Hindcoxal dorsum with outer margin sharply carinate near apex. Punctures of tergum I minute, averaging a few diameters apart on horizontal portion (anterior to apical depression). Sterna punctate throughout, punctures of sternum II averaging about 2-3 diameters apart mesally.

Setae silvery, appressed on frons, postocellar area, scutum, and tergum I, oriented obliquely ventrad on upper frons, on lower gena subappressed to suberect, curved, slightly shorter than midocellar diameter; completely concealing integument on clypeus (except lamella). Apical depressions of terga with silvery, setal fasciae.

Body all black, mandible dark reddish mesally in many specimens.

♀.– Upper interocular distance equal to 0.48-0.56 × lower interocular distance; ocellocular distance equal to 0.4 × hindocellar diameter, distance between hindocelli equal to 0.7-0.8 × hindocellar diameter; eye height equal to 1.06 × distance between eye notches. Free margin of clypeal lamella roundly arcuate ( Fig. 650 ). Dorsal length of flagellomere I 2.4-2.6 × apical width, of flagellomere IX 1.2-1.3 × apical width. Mandible: trimmal carina with minute incision shortly beyond midlength. Length 6.2-6.8 mm; head width 1.8-1.9 mm.

♂.– Upper interocular distance equal to 0.56-0.58 × lower interocular distance; ocellocular distance equal to 0.4 × hindocellar diameter, distance between hindocelli equal to 0.8 × hindocellar diameter; eye height equal to 1.08-1.12 × distance between eye notches. Free margin of clypeal

Figures

FIGURES 650-653. Pison modestum Pulawski, sp. nov. (650) Female clypeus and mandible; (651) Male clypeus and mandible; (652) Female propodeum in dorsal view; (653) Male propodeum in dorsal view.