Ithocritus similis Bi & Lin, 2020

Bi, Wen-Xuan, Chen, Chang-Chin & Lin, Mei-Ying, 2020, Notes on the tribe Petrognathini Blanchard, 1845 from China, with description of a new species from Yunnan (Coleoptera, Cerambycidae, Lamiinae), Zootaxa 4732 (3), pp. 453-460 : 455-457

Ithocritus similis Bi & Lin , sp. nov.

( Figs. 4, 5 , 10, 11, 14, 16 , 17, 20 )

Type material. Holotype: male, “ CHINA. Yunnan, Gongshan / Dulongjiang, Maku / 1500m, 2015.VIII.7 / leg. Xiao-Dong Yang ” ( SNUC) . Paratypes: 1 female, same locality as holotype “ 2015.VII.21 / leg. Chao Wu ” ( CCCC) ; 1 female, ditto “ 2015.VIII.9 / leg. Wen-Xuan Bi ” ( CBWX) ; 1 male, “ CHINA. Yunnan, Gongshan / Dulongjiangxiang / 1480m, 2017.VII.30 / local collector” ( CCCC) .

Description. Male ( Fig. 4 ). Body length 30.0– 32.5 mm, humeral width 10.0– 10.1 mm. Integument of body, antennae and legs blackish; elytra dark-brown. Head except for anterior margin of frons, genae and antennal insertions, pronotum except for sides and posterolateral margins, scutellum and most of elytra densely covered with yellowish-white pubescence. Elytron with blackish pubescent macula involving humerus, blackish pubescent macula near scutellum, and a few small irregular blackish spots near basal and apical third. Ventral sur f ace predominantly covered with fine blackish pubescence, except for anteromedian area of prosternum, most of mesanepisternum, posterior angle of metasternum, postmedian area of metanepisternum, sides of abdominal ventrite I to V, and anterolateral area of metacoxae covered with yellowish-white pubescence forming bright maculae.

Body elongate, subcylindrical, feebly narrowed posteriorly. Head slightly wider than pronotal base, occiput with several umbilicate punctures anteriorly; eyes emarginate, coarsely faceted; lower eye lobe 1.5 times as long as width, 2.2 times as long as gena. Antenna long and slender, about 2.7 times body length, finely punctate, basal 3 antennomeres sparsely fringed beneath with short setae; scape gradually thickened apically, with numerous granules near outer edge ( Fig. 11 ); 3rd antennomere 2.8 times as long as scape, 1.2 times as long as 4th, 1.5 times as long as 5th; relative length of antennomeres as follows: 3.5: 0.7: 10: 8.5: 6.9: 6.5: 6.0: 5.9: 6.7: 6.7: 11.6.

Pronotum broader than long, 0.7 times as long as basal width, width across lateral spines about 1.5 times of basal width; lateral spine stout, strongly thickened at base with acute apex; disk weakly convex, provided with several setigerous granules at sides after middle. Scutellum broadly rounded posteriorly. Prosternal process widened apically; procoxal cavities widely open posteriorly. Mesosternal process without tubercle and obliquely sloped in lateral view.

Elytra elongate, ca. 2.1 times as long as humeral width, slightly convergent toward conjointly rounded apices with short sutural teeth; sparsely provided with a few small granules near humeri; disk smooth, impunctate. Legs moderately long, stout; fore femora with coarse wrinkling sculpturing on both sides; metafemora reaching apical fourth of elytra; tarsus five segmented, tarsal claws divaricate.

Male genitalia. Tergite VIII, tegmen and median lobe as in Fig. 17 . Endophallus in everted condition ( Fig. 20 ) robust, about 2.3 times as long as median lobe, curved near apical third dorsally; APH defined, limit between BPH and MPH indicated by basal-lateral tubercle (blt); crescent-shaped sclerite absent; MPH subdivided into MT+CT and PB by constrictions, MT slightly longer than CT or PB; CT with lateral tubercles (ltc, Fig. 20d ) developed, elongate, directed forward, PB strongly swollen laterally near base, thence, in ventral view, gradually narrowed ( Fig. 20d ) or expanded in lateral view ( Fig. 20 ) toward apex; APH not subdivided, moderately swollen, weakly sclerotized dorsally from base to gonopore; apical furrow (af) with internal membrane (im) incomplete, represented by short dorsal appendix; spicules mainly distributed on ventral apical surface of MT and apical half of PB; ejaculatory ducts (ej) paired, gonopore (gn) situated near apex of dorsal side of APH.

Female ( Fig. 5 ). Body length 35.0– 35.5 mm, humeral width 11.1–11.4 mm. Almost identical to male in general appearance. Antenna about 2.0 times body. Head relatively larger, about 1.2 times wider than pronotal base. Abdo- men with ventrite V ( Fig. 16 ) widely protruded, apex 0.24 times basal width. Legs relatively slenderer and shorter, fore femora without wrinkling sculpturing.

Etymology. From the Latin, meaning similar or resembling, referring to the similarities between the new species and Ithocritus ruber .

Distribution. China: Yunnan (Gongshan County).

Remarks. Ithocritus ruber also occurs in the type locality of the new species. Both species share highly morphological similarities, especially regarding the yellowish-white colored individuals ( Figs. 3–5 ), but the new species can be distinguished by the metanepisternum and metacoxae provided with bright colored maculae (instead of absent); scutellum densely pubescent, obscuring integument (instead of with pubescence relatively sparser, not obscuring integument); elytra dark-brown (instead of reddish ochraceous); female with abdominal ventrite V widely protruded, apex 0.24 times as basal width (instead of 0.13 times); male with endophallus relatively more robust, CT with lateral tubercles developed, elongate, directed forward (instead of weakly developed), PB strongly swollen laterally near base, thence, in ventral view, gradually narrowed toward apex (instead of weakly swollen laterally and ventrally near base, thence strongly constricted toward subparallel-sided apex).

Figures

FIGURES 1–7. Habitus of three species. 1–3, Ithocritus ruber (Hope, 1839); 4–5, Ithocritus similis Bi & Lin, sp. nov.; 6–7, Falsimalmus niger Breuning, 1956. 1, 2, 4, 6, 7, male; 3, 5, female. 1–6, dorsal view; 7, lateral view. Not to scale.

FIGURES 8–16. Habitus of two Ithocritus species. 8, 9, 12, 13, 15, Ithocritus ruber (Hope, 1839); 10, 11, 14, 16, Ithocritus similis Bi & Lin, sp. nov. 8, 9, 10, scutellum; 11, scape (lateral view); 12, 13, 14, meso- and metathorax (lateroventral view), showing the bright pubescent maculae on mesanepisternum or metanepisternum; 15, 16, female abdominal ventrite V. Not to scale.

FIGURES 17–21. Male terminalia of three species. 17, 20, Ithocritus similis Bi & Lin, sp. nov.; 18, 21 Falsimalmus niger Breuning, 1956; 19, Ithocritus ruber (Hope, 1839). 17, 18, genitalia. 19, 20, 21, endophallus in inflated and everted condition (lateral view). a, tergite VIII with sternites VIII and IX in ventral view; b, tegmen in ventral view and lateral view; c, median lobe in ventral view and lateral view; d, apical part of endophallus (ventral view); e, enlarged apical part of endophallus (lateral view). 17, 18, scale = 1 mm; others not to scale.