Pseuderimerus burgeri Burks

Burks, R. A. & Redak, R. A., 2004, New species of Pteromalidae and Torymidae (Hymenoptera: Chalcidoidea) from California, with taxonomic notes, Zootaxa 606, pp. 1-20 : 17-19

Pseuderimerus burgeri Burks n. sp.

Diagnosis. Gaster greatly elongate in females:>0.6x total body length. Color pattern distinctive, with pale subbasal gastral blotch in both sexes, separated from longitudinal lateral pale strips by dark strip.

Description. Females. Total body length 1.8–2.6 mm (10.0–14.0 in relative units).

Color: Dark and pale forms present: dark forms almost entirely purple (Fig. 21), but pale forms (like the holotype in Figs. 17–18) extensively yellow. A few specimens are mostly orange instead, but differ in no other characters. Humeral plate, median longitudinal gastral blotch, and some isolated lateral gastral blotches always pale yellow to nearly white. Face at clypeal height varying from brownish to yellowish, but anterior tentorial pits always purple. Legs in dark specimens with at most all coxae, subbasal quarter of meso­ and metatibia, entire femur except for extreme base and apex, and apical tarsomeres brown. All of mandible except for periphery and denticles yellowish. Palps yellow. Eye reddish­gray, ocelli white. Antenna mostly brown but club gradually becoming yellowish, longitudinal sensilla white, radicle and base of scape yellow. Forewing and hind wing venation mostly white, brown at the edges, but basally entirely yellowish. Gaster with at least a row of dorso­lateral pale blotches on each side.

Sculpture: Head weakly imbricate to alveolate. Clypeus smooth. Pronotum, anterior parts of mesoscutum and axillae, and propodeum imbricate to transversely alveolate, but mesoscutum becoming more nearly isodiametrically alveolate for most of its length. Scutellum alveolate. Frenum with broader and shallower alveoli but otherwise undistinguished except at extreme lateral edges of frenal groove. Dorsellum with a row of tiny basal carinae, very shallowly alveolate. Prepectus, acropleuron, metapleuron, and upper mesepimeron glossy and smooth, the rest of the mesopleuron shallowly alveolate. Mesosoma with irregularly placed whitish setae.

Head width 2.1–2.7, height 1.9–2.5, length 1.2–1.5; dorsal IOD 1.2–1.5, ventral IOD 1.4–1.8; POL 0.5–0.6; OOL 0.3–0.4; EH 1.1–1.5; MS 0.4–0.6; MW 0.9–1.2; EL 0.9–1.1; TL 0.2–0.4; ocular setae inconspicuous, much shorter than diameter of an adjacent ommatidium; upper frons with impressed scrobal grooves diverging at their extremes, extending from beside the median ocellus to below the toruli, the grooves and scrobal depression with rounded edges; toruli 0.1–0.2 above lower eye margin, with a rounded longitudinal elevation between them; ITD 0.2–0.4; VTD 1.2–1.5; MTD 0.4–0.6; clypeus truncate. Scape 0.7–1.1:0.2–0.3, at rest not reaching median ocellus; pedicel 0.4–0.5:0.2–0.3; basal pair of flagellomeres comprising true anelli: distinctly shorter than the 3rd flagellomere and lacking longitudinal sensilla; all flagellomeres distinctly broader than long; 3rd–5th flagellomeres bearing 1 row of longitudinal sensilla, flagellomeres 6–11 with a second row partially overlapping the first; flagellar setae inconspicuous, shorter than longitudinal sensilla. Both mandibles with three denticles, the dorsal pair sometimes only weakly separated, denticles gradually longer and larger ventrally. Apical segment of maxillary palp with one long lateral apical seta, one medium supapical medial seta, and another medium dorsal seta basal to the latter. Labial palp fleshy and stoutest in middle, not appearing movably jointed.

Mesosoma (Figs. 17–18). Pronotal collar not formed, top of pronotum essentially flat in profile; lateral panel of pronotum broad and without a distinct scrobe, but broadly and shallowly concave from postero­ventral corner to its center; pronotal width 1.5–1.9; mesoscutum 1.3–1.7:1.7–2.1; scutellum 1.0–1.4:1.0–1.3; dorsellum extremely short; propodeum length 0.2–0.4, ISD 1.0–1.3; notauli complete; dorsal margin of prepectus as long or slightly longer than tegula; transepisternal sulcus not indicated, acetabular, mesopleural, and transepimeral sulci distinct; axillae only slightly advanced anteriad of scutellar margin, axillar separation 0.3–0.4; axillulae tiny; frenal groove indicated only at lateral extremes. Propodeum smooth centrally, with a row of very short anterior carinae at the plical area, and a pair of tiny submedian carinae medially that extend less than half the propodeal length; spiracles oval; callus with 8–9 short setae that become gradually longer posteriorly; nucha hardly present: its length less than half the short axis of the spiracles. PRF 1.3–1.9:0.4–0.6; PRT 1.2–1.7:0.2–0.3; MSF 1.4–1.7:0.4–0.5; MST 2.0–2.4:0.2–0.3; mesotibial spur 0.2–0.3; basal mesotarsomere 0.6–0.8; MTF 1.6–2.3:0.5–0.7; MTT 2.2– 3.2:0.2–0.3; metatibial spur 0.2–0.3; basal metatarsomere 0.6–1.0; metacoxa with a row of tiny dorso­basal setae much shorter than the long, erect dorso­apical setae. FW 6.3– 8.2:2.3–3.0; CC 2.3–3.2; MV 1.0–1.4; PMV 0.6–0.9; SV 0.3–0.4, shortest distance from uncal apex to PMV 0.1, from stigmal apex to PMV 0.3–0.4; uncus slightly longer than maximum stigmal width; costal cell with one row of ventral setae along its entire length and several additional ventral setae in apical half; speculum closed posteriorly by cubital setal track, extending to stigmal base and exposing about three vague rows of short admarginal setae; basal cell with some dorsal setae in its apical half; basal fold setose, its posterior half strongly arching towards forewing base; cubital setal track complete. HW 4.2– 5.8:0.8–1.1.

Petiole very short, several times broader than long. Gaster length (not including ovipositor sheaths) 6.0–9.2; gaster poorly sclerotized dorsally, appearing membranous, dorsal apical edges of tergites almost impossible to discern through an optical microscope; 5th and 6th gastral tergites the longest, apex of 3rd gastral tergite extending to that of the 4th; hypopygium extending 3.0–5.5 from gastral base, with a small apical notch; ovipositor sheaths extending 2.6–5.5 beyond gastral apex.

Males. (Fig. 19–20): Body length 1.1–2.0 mm (6.0–11.0 in relative units). Color and patterns as in females but frequently more nearly brownish. Like female except for the following characters: EH 0.7–1.3; MS 0.4–0.5; head width 1.5–2.5, height 1.3–2.3, length 0.8–1.5; scape 0.5–0.9:0.2–0.3; pedicel 0.3–0.5:0.2; flagellum sometimes with 3rd flagellomere anelliform and lacking longitudinal sensilla; propodeum longer: length 0.2– 0.4, ISD 0.8–1.4; gaster much shorter: length 3.2–5.4; genitalia (Fig. 20) with long, curved parameres extending well beyond volsellar apex, with two apical setae; volsellae truncate apically and with a digital spine at each corner; intervolsellar process present and extending only slightly beyond volsellar apex.

Variation: Some females have a distinctly shorter and narrower forewing than others, but this varied within localities and followed no discerned pattern; the holotype has relatively broad wings. Very small specimens have relatively narrow metafemora and metatibiae.

Host: Unknown. It has been hypothesized (E.E. Grissell, personal communication) that it may parasitize Tetramesa Walker (Eurytomidae) in grass stems, but we have not been able to find or rear it or Tetramesa in subsequent visits to known collection sites, despite extensive searching throughout its known seasons of occurrence.

Distribution: San Diego, Riverside, Solano, and Napa Counties, California, USA, all from coastal sage scrub or chaparral habitat.

Etymology: This species is named in honor of Jutta Burger, whose hard work and dedication in collecting and processing samples from the Lake Skinner area were instrumental in acquiring critical specimens of the species described in this publication.

Material examined: Holotype Ψ USA: CA: San Diego Co. Miramar Naval Air Station 32°55 N 117°0 W elev. 290m 10.viii.1998 Redak Lab UCR (USNM). Allotype ɗ USA California, Riverside Co. Menifee Valley (hills on W. end) 33°39 N 117°13 W 1800’ 19– 31.vii.1995 J.D. Pinto MT (USNM). 1 Ψ paratype San Diego Co. Miramar Naval Air Station 32°53 N 117°0 W elev. 167m. 40­50 Legacy GC6 (UCRC). 1 ɗ paratype Riverside Co. Menifee Vly (Hills on W. end) 33°39 N 117° 13 W. 1800’el. Iv.18.1999 John D. Pinto (UCRC). 1 ɗ paratype Riverside Co. Lake Skinner (NE end) 33°36 N 117°2 W 11.vi.1996 U9#1 Redak Lab UCR (UCRC). 1 Ψ paratype Riverside Co. Lake Skinner (NE end) 33°36 N 117°2 W 11.vi.1997 B3 Redak Lab UCR (UCRC). 1 ɗ paratype Riverside Co. Lake Skinner (NE end) 33°36 N 117°2 W v­7/21 ­1996, J.D. Pinto MT Coastal Sage Scrub MET U11, UNBURNED (UCRC). 1 Ψ and 4 ɗɗ paratypes Riverside Co. UCR Campus Coll. J. Huber In pan trap [collection dates between 18.iv.1981 and 3­vii.1981] (UCRC). 1 Ψ paratype Solano Co. Cold Canyon Rsrv. 11 km W. Winters 23.iv.1992 S.L. Heydon (UCDC). 24 Ψ and 47 ɗ paratypes Solano Co. Cold Canyon Rsrv. 11km W. Winters on Daucus pusillus S.L. Heydon [collection dates between 23.iv and 18.viii of 1991– 1993] (UCDC). 2 Ψ paratypes Napa Co. Lake Hennessey 10km E. St. Helena 7.ix.91 S.L. Heydon off Heracleum (UCDC).

Placement. This species possesses several characters that place it in the genus Pseuderimerus as defined by Grissell (1995): club with apical spicule, more than one anellus, only one metatibial spur, no occipital carina, metafemur without ventral denticles, and marginal vein <2.5x postmarginal vein length, <4.5x stigmal vein length. It may lack one of the apomorphies used by Grissell to define the genus: the eyes in males are not as much smaller than those in females; this character is only inconsistently observable in P. b u rg e r i. Pseuderimerus burgeri differs from all other species in the genus in the unusually long gaster in females and constitutes a very distinct element within the genus. We consider neither character to be of generic value. E.E. Grissell (personal communication) agrees with our placement of this species.