Systellus Kleine, 1917

Maruyama, Munetoshi, Morimoto, Katsura, Bartolozzi, Luca, Sakchoowong, Watana & Hashim, Rosli, 2014, On the myrmecophilous genus Systellus Kleine (Coleoptera: Brentidae), with systematic and biological notes on S. mentaweicus (Senna), Raffles Bulletin of Zoology 62, pp. 805-811 : 805-806

Systellus Kleine, 1917

Systellus Kleine, 1917a: 175 (type-species: Systellus rex Kleine 1917 , by original designation); Alonso-Zarazaga & Lyal, 1999: 49 (= Eusystellus , unjustified replacement name); Sforzi & Bartolozzi, 2004: 321 (catalogue).

Eusystellus Kleine, 1917b: 316 (replacement name for Systellus Kleine, 1917 , not Systella Westwood, 1841 ); Kleine, 1920: 238 (key); Kleine, 1924: 204 (redescription); Kleine, 1926: 35 (male description); Kleine, 1927a: 80 (key); Kleine, 1927b: 31 (catalogue); Kleine, 1937: 28 (key); Kleine, 1938a: 12 (catalogue); Kleine, 1938b: 76, 78 (redescription); Damoiseau, 1979: 3, 21 (key and female redescription).

Eurystellus: Kleine, 1931: 307 (misspelling).

Redescription. Male: Head ( Figs. 1–4 ) short, twice as wide as long to basal constriction, with three longitudinal sulci on vertex; eyes large, occupying almost entire side margin of head, strongly convex laterally, contiguous with basal constriction at base; antennae ( Fig. 5 ) with nine segments, weakly asymmetrical; rostrum longer than wide, separated from head by deep transverse depression at base; metarostrum short, mesorostrum subquadrangular, parallel-sided, broadly depressed dorsally, longitudinally carinate along side margins; prorostrum narrower than mesorostrum, convex at sides, longitudinally depressed in the middle, connected to mesorostrum, costate at each side of depression, costae incurved along antennal insertion from anterior margin of mesorostrum, auriculate on each side of the costa; rostral apophyses well expanded laterally beyond meso- and metarostrum; underside of pro- and mesorostrum strongly compressed laterally on each side of median carina,latter well produced and arcuate ventrally, narrowest between antennal sockets in ventral view and distally enlarged with a pair of narrow sulci to bottom of hypopharyngeal sinus, each side of medial carina broadly depressed.

Pronotum ( Fig. 1 ) longer than wide, punctuated, with trace of median sulcus on disc. Scutellum not visible.

Elytra ( Fig. 1 ) parallel-sided, slightly wider than pronotum, lamellate at apex, striae very narrow, with row of punctures, intervals wide, depressed along entire length, with costate sides, seventh interval with row of 9 distinct umbilicate pores ( Fig. 6 : arrows).

Legs ( Figs. 1, 7 ) robust, femora compressed from base to middle; tibiae bisinuate internally, compressed with weak swelling at basal third, tibial spurs 1-2-2.

Prosternum between coxae linear. Metasternum with median sulcus on posterior half. Venter not sulcate; sternite III behind coxa shorter than IV, sternite VIII truncate at apex, with large depression in middle.

Female: Head ( Figs. 8–10 ): similar to male, but prorostrum short, cylindrical, slightly upturned towards apex, with weak median sulcus at base; underside without carina; mesorostrum weakly expanded laterally below antennal sockets; head and rostrum without conspicuous setae; sternite VIII without depression.

Figures

Figs. 1–7. Systellus mentaweicus, male (from Ulu Gombak, Selangor, Peninsular Malaysia): 1, Habitus, dorsal view; 2, ditto, ventral view; 3, head, dorsal view; 4, ditto, ventral view; 5, left antenna; 6, umbilicate pores on right elytra; 7, right fore leg. Scale bars = 1.0 mm.

Figs. 8–10. Systellus mentaweicus, female (from Ulu Gombak, Selangor, Peninsular Malaysia): 8, Habitus, dorsal view; 9, ditto, ventral view; 10, head, ventral view. Scale bars = 1.0 mm.