Parorthomus socotranus B. Gueorguiev

Body length 8.2–10.0 mm (9.2 mm in holotype); width 3.2–3.9 mm (3.6 mm in holotype), maximum width behind the middle of elytra. Head, pronotum, elytra, segments III–IV (in the most cases) of antennae, and ventral surface (without mouthparts) black in mature specimens, light to dark brown in immature specimens; labrum, mandibles, mentum, segments I–II and V–XI of antennae, and sometimes sides of pronotum testaceus; maxillary palpomeres, labial palpomeres, and labium rufous; coxae, femora, and tibiae of legs dark brown or testaceus, trochanters and tarsomeres mostly rufous. Microsculpture distinct on the whole dorsal and ventral surfaces (including coxae, trochanters and femora), consisting of isodiametric and slight transversal meshes, more apparent in females (female specimens almost matt on dorsal surface, males somewhat shiny), reduced on the most part of the clypeus and gula. Head noticeably longer and narrower with respect to the pronotum, frons smooth, frontal furrows well-marked, divergent posteriorly, reaching the level of anterior supraorbital punctures; neck without constriction posteriorly; eyes fairly large, convex, moderately prominent, with diameter as long as the combined length of segment I-II of the antennae, temporae short, as long as or shorter than half of eye diameter; paraorbital sulci moderately deep, encircling eyes behind; clypeus trapezoidal, separated from frons by fine suture, with anterior margin slightly concave; labrum rectangular; antennae moderately long, pubescent from second fourth of segment IV, the apex of terminal segment not reaching basal margin of pronotum; mentum transverse, deeply emarginate, with large labial pits, median tooth slightly bifid at tip, epilobes narrow, slightly projecting beyond lobes; submentum with medial setae, without lateral ones (Fig. 28). Pronotum wide, transverse, sub-trapezoid, widest about middle, with margins distinctly, narrowly bordered (the bordering reduced in the middle quarter of apical margin, and sometimes in the middle of basal margin, just between the internal basal impressions); sides somewhat more constricted apically than basally, with two pairs of setiferous punctures, lateral punctures situated at about end of apical third, posterolateral ones situated near hind angles, near to lateral margin and close to basal margin; apical margin moderately emarginate, narrower than basal margin, fore angles rounded, moderately projecting; basal margin nearly straight, slightly concave in the middle, hind angles almost rectangular, rounded at tip; basal impressions somewhat variable in extension and size, internal ones always present, linear, narrow and falcate, diverging toward base, impunctate, deeper and longer than the outer ones, outer impression present or reduced becoming evanescent, when present then mostly faint, foveolate, somewhat punctate; disc slightly convex, midline well-impressed, long, not reaching both anterior and posterior margins. Elytra sub-elongate, moderately convex, widest at about the second third, fused at suture; shoulders well-marked, obtusely angulate; basal margin complete, reaching stria 1 inwards, forming a very minute denticle at humerus; discal striae moderately impressed, impunctate, parascutellar striae distinct, striae 1-8 joining basal margin; intervals slightly flat, smooth, interval 3 with three to four (rarely two or five) setiferous punctures adjoining stria 3, with last puncture in posterior third of elytron, rarely in about middle of interval 3 (see also Variability); scutellar setiferous puncture present; hind wings reduced to small scales. Prosternum, mesosternum, middle of metasternum, proepipleura, epipleura of elytra, and abdominal sternites (excl. sides of sternites 1-3) smooth, impunctate, proepisterna and sides of sternites 1-3 slightly punctured, mesepisterna, metepisterna, and sides of metasternum more or less roughly punctured; intercoxal process of prothorax subquadrate, distinctly bordered at sides and backwards; metaepisterna short, sub-quadrate, moderately narrowed toward behind, its anterior border longer than internal and posterior ones, as long as external border. Abdominal sternites IV-VI with transverse basal sulci complete (continuous) and well-impressed, abdominal sternum VI with posterior margin rimmed throughout, with one pair of foveate setigerous punctures medially in males and two pairs in females. Legs slender, relatively long; protibia apically moderately but abruptly enlarged at internal margin in males; mesotibia and metatibia straight in both sexes, mesotibia with slight inner callus distally in males; tarsomeres 1-5 glabrous dorsally, segment 5 setose ventrally; segments 1-3 of male protarsi moderately expanded. Male genitalia (5 specimens dissected). Median lobe of aedeagus slender (Figs 19–20), narrower at middle, with basal part long, almost rectangularly bent behind apical part, narrowest at middle, from there toward apical lamella rectilinear, right external angle of apical lamella somewhat bent down, left external angle elevated (left lateral view), median lobe from middle part shifted to left, with right margin moderately convex, lengthwise appreciably elevated over left margin, left margin concave towards apex, apical lamella wide, rounded on left side, obtusely angled on right side, with a slight front concavity (dorsal view), ostium slightly deflected to right; right paramere narrow and elongate, smaller than left one, with a slanting lateral process (Fig. 21); left paramere conchoid (Fig. 22). Female genitalia (3 specimens dissected). Ovipositor (Fig. 23), with valvifer more chitinized proximally and less distally, its distal margin having a setose and moderately chitinized area, basal stylomere large, conical, apical stylomere smaller, falcate, with two dorsolateral ensiform setae and one dorsomedial ensiform seta, sensorial pit distinct with two long nematiform setae; spermathecal complex (Fig. 24) with copulatory bursa proximally slightly gooseneck-like (this character not visible in Fig. 24), spermatheca with seminal canal and receptaculum slightly differentiated [undifferentiated type, according to Bousquet 1999: 35-36], receptaculum shorter than seminal canal, widened and slightly curved apically, appended spermathecal gland spherical, with elongate diverticulum.

Up to present only known from Socotra.