Usia theodori Gibbs, 2011

Gibbs, David, 2011, 2960, Zootaxa 2960, pp. 1-77 : 68-70

Usia theodori Gibbs sp. nov.

( Figs. 16 & 18, Plate XX)

Usia (?) carmelitensis: Theodor, 1983: 61 Figs. 162–167, misidentification.

Type material examined. HOLOTYPE: Israel, Dunes Akko, Coastal Plain, Palestine, 8 April [19]54, O. Theodor [♂ in TAU] . PARATYPES: Israel, Dunes Akko , Coastal Plain, Palestine, 8 April [19]54, O. Theodor [9♂ 12♀ in TAU]; 19 May 1954, Cea Savea (dunes), Coll. Krystal J. [♀ in TAU]; Herzliyya, 13 March 1995, leg. B. Merz [♀ in MHNG] .

Etymology. Named after Oskar Theodor, who first illustrated the genitalia of this species ( Theodor 1983: 61).

Diagnosis. A small entirely black species, teneral or faded specimens browner, only known from the coastal strip of Israel. Identifiable by a combination of short adpressed hairs on ventral side of hind femora, hairs on margin of scutellum about as long as length of scutellum medially and details of genitalia. Male epandrium fairly large and conspicuously constricted medially in dorsal view with elongated, clavate lobes apically that fold round the cerci in dried specimens. Female sternite 8 is conspicuously raised proximally to form forwardly directed boss that almost protrudes beyond the proximal margin of this sternite. Details of male and female genitalia diagnostic.

PLATE XX. Usia theodori Gibbs sp. nov.; a epiphallic complex ventral, b epiphallic complex lateral, c gonocoxite ventral, d gonocoxite lateral, e epandrium dorsal, f epandrium lateral, g female genitalia ventral, h female sternite 8 ventral.

Description. Measurements. Body length. 1.6–3.0mm Wing length. 1.6–2.8mm.

Male. Head. Frons a little more than a fifth, sometimes almost a quarter, head width, at narrowest point as wide just wider than length of third antennal segment, rather matt with no more than inconspicuous anterolateral dust spots, front of frons close to antennal bases often obscurely brown. Mouth margin exceedingly narrow, essentially absent. Ocellar triangle obtuse, lateral ocelli separated from the eye by less than their diameter. Longest hairs on ocellar tubercle about as long as or longer than width across frons at vertex. Occiput covered with grey dust obscuring ground colour, marginally more thinly so on triangular area behind vertex. Black hairs on occiput short above, longer below, those on ventral side of head even longer than those hairs on ocellar tubercle. Antennae black, relatively short, third segment long-obovate, about twice as long as scape and pedicel combined. Antennae largely bare dorsally but with a few short setulae just before the apical sulcus. Proboscis black, naked, relatively short, about as long as mesonotum. Palps very small, black to brown, clavate with small apical setae as long as the palps. Thorax. Entirely black, mesonotum shining and mostly smooth to inconspicuously wrinkled with hair insertions apparent but not strongly marked, thinly dusted on pronotum, postpronotal lobe, notopleuron and posterior part of mesonotum adjacent to scutellum. Mesonotum with fairly long, scattered, perpendicular black hairs, acrostichals biserial, clearly separated by bare paramedian lines from lateral hairs, latter generally distributed, the longest almost as long as the length of third antennal segment. Scutellum smooth, surface thinly dusted on anterior half, disc almost bare, just a few long black hairs, hind margin with a somewhat irregular, in parts uniserial, row of long, upwardly directed black hairs the longest almost as long as scutellum is long. Pleura black to dark brown, subshining but with thin pale dusting covering all but lower anterior corner of anepisternum all of meron, propleuron and more thinly so, dorsum of katepisternum. Dorsal half of anepisternum with shortish black hairs. Wing. Clear, the veins pale brown. Anal lobe convex, about as wide as anal cell, r-m before middle of discal cell. Haltere. Whitish knob, stem slightly infuscated basally. Legs. Black to dark brown, shining but with rough texture to cuticle, with very short, adpressed black hairs, those on the femora generally longer than those on tibia. Tarsi about as long as respective tibia, segments 1–5 steadily decreasing in length. Abdomen. Black, short with broad tergites, middle ones often exceedingly short, surface sculpture obscure, no more than inconspicuous transverse welts and hair insertions. Basal tergites laterally dulled by a coating of pale dust, visible dorsally on tergite 1 only. Disc of tergites covered with relatively short black hairs, lateral hairs a little longer. Sternites grey-dusted with apical fringes of short, dark hairs. Genitalia. Large and globular, occupying most of venter of abdomen, larger than the abdomen and often obscuring the sternites. Epandrium evenly convex with very conspicuous apical clavate extensions, viewed caudally these can be seen to encircle the cerci, disc of epandrium with short dark hairs. Viewed dorsally lobes of gonocoxite only just protrude beyond the apical sternite, divided by a relatively shallow sulcus. Gonocoxite with perpendicular black hairs as long as any elsewhere on the insect. In pinned specimens the shiny, rounded, apicolateral lobes of the gonocoxite are clearly visible. Epiphallus short, not extending much beyond aedeagus.

Female. Very like the male, frons noticeably wider, mouth margin broader so quite apparent and disc of abdomen shorter haired. Tergites less clearly dusted, dusting thin and largely confined to tergite 1. Cerci normal. In pinned material sternite 8 is conspicuously raised proximally to form forwardly directed boss that almost protrudes beyond the proximal margin of this sternite. When dissected the apical processes (sternite 9) lightly sclerotised, yellowish with a clear U-shaped notch between them.

Discussion. A very distinctive species not obviously affiliated to any of the other Micrusia . The genitalia show some characters in common with those of U. forcipata but other characters do not support a close relationship with this species.

Distribution. Israel. So far only known from three sites, all probably dunes, along the coastal strip of Israel. Only at one of these has it been found in any numbers so this exceedingly local species is likely to be endangered.