Psomizopelma Gibson

Gibson, Gary A. P., 2018, The species of Psomizopelma Gibson (Hymenoptera: Eupelmidae), Zootaxa 4444 (1), pp. 73-91: 74-75

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Psomizopelma Gibson


Psomizopelma Gibson 

Psomizopelma Gibson, 1995: 255  –258. Type species: Psomizopelma brachypterum Gibson  , by monotypy and original designation.

Diagnosis. FEMALE. Body usually mostly yellow (e.g. Figs 44, 45 View Figure ) to dark brown (e.g. Figs 17, 18 View Figure ) except gaster with all but apical one or two sternites and at least Gt1 and Gt2 and sometimes Gt3 laterally white ( Figs 8 View Figure , 24 View Figure , 33 View Figure , 45 View Figure , 62 View Figure ), though sometimes with quite distinct metallic luster on head and mesosoma ( Fig. 54 View Figure ) and gaster dorsally ( Fig. 62 View Figure ); body (excluding appendages) mostly meshlike reticulate to punctate-reticulate, though sometimes acropleuron or gaster much more finely sculptured than rest of body.

Head in lateral view comparatively flat, lenticular ( Figs 2 View Figure , 18 View Figure , 33 View Figure ), and in frontal view ( Figs 3 View Figure , 19 View Figure , 34 View Figure , 46 View Figure , 56 View Figure ) subcircular to somewhat transversely oval with comparatively large, densely setose, elongate-oval eyes with subparallel inner margins extending most of height of head such that malar space only about one-quarter to one-third height of eye; entirely setose except for variably extensively bare scrobes; scrobal depression more or less bell-shaped but lacking distinct margins except for sinuous, carinate margin lateral of torulus; toruli inserted much closer to oral margin than middle of head, ventral margin separated from oral margin by distance only about equal to height of torulus ( Figs 4 View Figure , 20 View Figure , 35 View Figure , 47 View Figure , 57 View Figure ). Mandible tridentate ( Figs 4 View Figure , 57 View Figure ). Antenna ( Figs 4 View Figure , 36 View Figure , 41– 43 View Figure , 59 View Figure ) variable in colour pattern, entirely dark to partly pale; clavate; fl1 longer than wide, subequal in length or longer than fl2; clava large, subequal in length to combined length of apical 4–6 funiculars, and in ventral view with variably conspicuous sensory region along most or entire length ( Figs 4 View Figure , 43 View Figure ).

Brachypterous (fore wing extending at least to base of gaster but for less than half length of gaster, Figs 1 View Figure , 17 View Figure , 32 View Figure , 54 View Figure ) or macropterous (fore wing extending about to apex of gaster, Figs 44, 45 View Figure ). Fore wing densely setose and infuscate with orangish to dark brown setae, without hyaline regions with white setae ( Figs 7 View Figure , 23 View Figure , 38 View Figure , 52 View Figure , 61 View Figure ). Mesosomal structures similar in both brachypterous and macropterous forms except mesoscutum with distinct, convex, triangular medial lobe only in macropterous female (cf. Figs 5 View Figure , 48 View Figure : arrow). Pronotum in dorsal view subtriangular, medially divided with dorsal surface in single plane, without differentiated collar and neck ( Figs 1 View Figure , 17 View Figure , 44 View Figure , 48 View Figure ). Prepectus ( Figs 6 View Figure : pre, 21, 49, 58) comparatively short, not extending posteriorly to base of tegula ( Fig. 6 View Figure : tg, 21, 37, 49, 58); bare or setose. Metapleuron ( Fig. 22 View Figure : pl3) bare or setose, separated by more or less distinct carina (e.g. Fig. 50 View Figure : arrow) from more horizontal, quadrangular, setose metasternal surface ( Fig. 22 View Figure : st3; Gibson 1995, fig. 138: lpl) separating acropleuron from base of metacoxa ( Figs 22 View Figure , 50 View Figure ). Mesotibia with apical groove (e.g. Gibson 1995, fig. 329: mag) and with apical pegs over base of tibial spur (e.g. Gibson 1995, fig. 327: map); mesobasotarsomere ventrally with single row of pegs along either side (e.g. Gibson 1995, fig. 328: mpg), the pegs similar in color to tibia. Metafemur in lateral view sometimes with dorsal margin undulating ( Fig. 2 View Figure ) or femur distinctly expanded subapically ( Figs 18 View Figure , 60 View Figure ); metatibia strongly compressed dorsally, unicolorous dark ( Fig. 40 View Figure ) or with dorsal margin paler ( Figs 2 View Figure , 45 View Figure ) and sometimes with variably distinct ‘notch’ along dorsal ( Fig. 60 View Figure ) or ventral margin ( Fig. 40 View Figure ). Propodeum with carinate margins of foramen sinuately or arch-like incurved to anterior margin, differentiating uniformly meshlike reticulate plical and callar regions ( Fig. 51 View Figure ).

Gaster ( Figs 8 View Figure , 24 View Figure , 39 View Figure , 53 View Figure , 62 View Figure ) with posterior margins of tergites transverse except Gt5 emarginate; syntergum extended posteriorly into syntergal flange over only slightly protruding ovipositor sheaths.

MALE. Head structure, setation and sculpture ( Figs 11 View Figure , 27 View Figure ) similar to female except for antennal structure and malar space longer, about 0.4× eye height. Antenna ( Figs 12 View Figure , 28 View Figure ) with pedicel almost as long as combined length of fl1 and fl2, and ventrally without line of long setae; flagellum variably distinctly robust-filiform with multiple rows of inconspicuous mps beyond fl1; fl1 almost as long to somewhat longer than wide, but slightly shorter than fl2, without mps; clava of same width as and at least as long as combined length of apical three funiculars, and tapered to point apically without distinct micropilose sensory region. Mesosoma not unusually modified for male Eupelminae  ( Figs 13, 14 View Figure , 30 View Figure ); metapleuron with 2–5 setae ventrally; metasternal region ( Fig. 30 View Figure : st3) much smaller and less conspicuous than for female, but separated from metapleuron ( Fig. 30 View Figure : pl3) by carina and separating mesepimeron from base of metacoxa ( Figs 14 View Figure , 30 View Figure ) similar to female. Fore wing ( Figs 15 View Figure , 29 View Figure ) without speculum; disc at least slightly infuscate behind marginal vein. Metatibia less distinctly compressed than for female, but sometimes with dorsal margin paler ( Fig. 10 View Figure ) as for female.

Discussion. Females of Psomizopelma  can be distinguished from those of all other genera except Taphronotus Gibson  by their comparatively short prepectus ( Fig. 6 View Figure : pre) that apically is conspicuously separated from the base of the tegula ( Figs 6 View Figure : tg, 21, 49, 58) (Gibson 1995, character 20, state 2, table 1). A more comprehensive description of both sexes is given by Gibson (1995), though some modifications to this are necessitated by the newly described species. The discovery of P. metallicum  females demonstrates that at least the head ( Figs 54–57 View Figure ) and mesosoma dorsally ( Figs 54, 61 View Figure ) can have quite distinct metallic lusters. Males of P. metallicum  are unknown and therefore it is unknown whether they display similar metallic lusters, but this is possible because the larger P. albiclava  male exhibits slight but distinct metallic luster ( Fig. 11 View Figure ). This contradicts Gibson’s (1995) couplet 13(12) for males, which keys out Psomizopelma  . The discovery of P. albiclava  males also falsifies some other statements in the couplet and the generic diagnosis. Relative length of the OOL for P. albiclava  males differs from that stated in the key and generic diagnosis of Gibson (1995), the flagellar segments, including fl1, are all quite obviously longer than wide ( Fig. 12 View Figure ), and the body is not uniformly dark brown but has some yellowish regions ( Fig. 13 View Figure ) in addition to sometimes slight metallic luster. However, Psomizopelma  males are quite readily identifiable to genus because head structure ( Figs 11 View Figure , 27 View Figure ) is otherwise similar to that of females ( Figs 3 View Figure , 19 View Figure ).

Homology of the lateral surface of the metathorax remains somewhat uncertain in Psomizopelma  , but females have a vertical, sculptured, bare or setose region that here is interpreted as the metapleuron ( Fig. 22 View Figure : pl3). Ventrally this region is separated by a variably well-developed transverse carina ( Fig. 50 View Figure : arrow) from a more horizontal, setose region that is here interpreted as an exposed part of the metasternum ( Fig. 22 View Figure : st3), which separates the posterior of the acropleuron from the base of the metacoxa ( Figs 22 View Figure , 50 View Figure ). Males are known for only P. albiclava  and P. brachypterum  . Females of P. albiclava  have setae on both the presumptive metapleuron and metasternum (cf. Fig. 50 View Figure ) whereas females of P. brachypterum  have setae only on the presumptive metasternum ( Fig. 22 View Figure ). Males of both species have setae ventrally on the presumptive metapleuron whereas the presumptive metasternum is bare ( Figs 14 View Figure , 30 View Figure ), though a transverse carina below the setae is visible in males that distinguishes the much smaller presumptive metapleuron.

The presence of P. brachypterum  and P. metallicum  in Florida, as the only two species from the Nearctic region, indicates Psomizopelma  is restricted to the tropical and subtropical regions of the New World.












Psomizopelma Gibson

Gibson, Gary A. P. 2018



Gibson 1995: 255


Psomizopelma brachypterum

Gibson 1995