Rueckeria nigrileonis, Arriaga-Varela, Emmanuel, Tomaszewska, Wioletta, Huo, Lizhi & Seidel, Matthias, 2018

Arriaga-Varela, Emmanuel, Tomaszewska, Wioletta, Huo, Lizhi & Seidel, Matthias, 2018, On Neotropical Merophysiinae with descriptions of a new genus and new species (Coleoptera, Endomychidae), ZooKeys 736, pp. 1-41 : 19-22

Rueckeria nigrileonis sp. n. Figs 7c, d, 9, 14a, b, 17

DNA barcode.

GenBank accession number: MG676232

Etymology.

This new species is dedicated to our coleopterist colleagues in the entomological collection of the University of Guadalajara, whose mascot is a black lion. The name is derived from Latin “niger” (black) and “leo” (lion).

Differential diagnosis.

Rueckeria nigrileonis is most similar to R. puma by its small size and black body with legs, antennae and mouth parts yellow (Fig. 9 a–c). However it can be distinguished by the pronotum being less narrowed at base (1.05 times wider at widest part than at base) (Fig. 17b), abdominal postcoxal lines regularly rounded, shallower, reaching about 1/3 length of ventrite 1, and the aedeagus with the tegmen longer than the median lobe with apex rounded and the median lobe moderately widened at base and curved (Fig. 9 d–f).

Description.

Length 1.29-1.37 mm, width 0.67-0.71 mm, height 0.5 mm; body moderately elongate-oval, moderately convex, 1.92-1.95 times as long as wide, 2.80 -2.95 times as long as high (Figs 9 a–c, 14a, b). Surfaces shiny, sparsely covered with very short, decumbent, golden setae. Color mainly black with ventral surfaces infuscate yellow, clypeus reddish brown and mouth parts and legs yellowish.

Head with interocular distance 0.8 times as wide as head including eyes. Eyes small, composed of 18 facets. Antenna moderately long and slender, 0.85 times as long as head and pronotum combined; scape 1.33 times longer than wide, 1.33 times as long as pedicel; pedicel 1.36 times longer than wide; third antennomere 1.66 times longer than wide, equal in length with pedicel; antennomeres 4-8 getting gradually shorter and wider towards antennomere 9 which is as long as wide and 0.7 times longer than pedicel; terminal antennomere inflated, asymmetrical, 2.25 times as long at longer margin as pedicel, its longer margin 1.45 times longer than lateral one and 1.05 as long as apical margin, apical margin truncate. Mentum subquadrate, weakly produced anteriorly in middle of anterior margin (Fig. 17a).

Pronotum weakly transverse (Fig. 17b), 0.75-0.80 times as long as wide, 1.41 times wider than head, 1.05 times wider at widest part than at base, widest at anterior fourth, strongly convex in mid length; front angles rounded, weakly produced; lateral margins slightly sinuate, narrowing at basal third, narrowly bordered with edges very weakly crenulate; hind angles right-angled to weakly obtuse, rounded at tips. Anterior half of disc without impressions. Longitudinal sulci weakly convergent, reaching nearly half length of pronotum; basal lateral pores present, connected by deep, faintly defined transversal sulcus; posterior transverse sulcus provided with large foveate punctures, area between transverse sulci convex, weakly depressed at mid-line; posterior margin weakly lobed at mid-line. Prosternal process widely separates front coxae, widest at mid length (Fig. 17e).

Elytra 0.80-0.88 mm long, 1.18-1.24 times longer than wide; 2.10-2.20 times as long and 1.31-1.38 times as wide as pronotum; widest at basal fourth then continuously strongly converging to rounded apex. Punctation composed of small setiferous punctures, each accompanied posteriorly by 2-3 slightly larger shallow foveate punctures (Fig. 17c).

Legs moderately long. Femora very narrow at base, strongly widened at apical half. Pro- and mesotibiae very narrow, slightly curved inwards, parallel sided along basal 2/3, then widened towards apex. Metatibia very narrow, almost straight, continuously widening apically, more accentuated at apical fifth, 0.38-0.42 times as long as elytra. Metatarsus long, 0.68 times as long as metatibia.

Abdomen with ventrite 1 slightly shorter than metaventrite and as long as three following ventrites combined (Fig. 17f); postcoxal lines on ventrite 1 weakly asymmetrically rounded, complete. Ventrite 5 rounded at apex.

Male genital segment with sternite emarginate apically, and acuminately rounded at its base. Tegmen large, slightly curved in lateral view, with rugouse apex. Median lobe short, markedly curved, continuously strongly narrowing to acute apex. Tegminal strut absent (Fig. 9 d–f).

Female genitalia with moderately broad coxites with two apical setae, styli vestigial; spermatheca large, subreniform (Fig. 9g).

Type material.

Holotype, male, MEXICO "Mexico: Veracruz. Tlalnehuayocan, Río Pixquiac, Fragmented cloud forest, 1522 m 19°32'4.9"N 96°59'52"W, Sifted leaf litter, 5.V.2013. Leg. E. Arriaga, F. Alvarado & R. Madrigal (NMPC). Paratypes, "Mexico: Veracruz Trucha Feliz, 1 km SW of Rancho Viejo (W of Xalapa) 19°31.1'N 96°59.1'W; 1445 m 9.ix.2016; Alvarado, Arriaga, Fikáček & Seidel lgt. 2016-MX15 / sifting of accumulations of leaf litter in small pieces of riverside forest" (1 male: CZUG); "Mexico: Veracruz, Coatepec, Reserva La Cortadura, 12 km NV Coatepec town, 1900-2000 m, Fragmented cloud forest, Sifted leaf litter, Winkler extractor, 20.VI. 2012, F. Alvarado & R. Madrigal" (1 female: MIZ); "MEXICO: Veracruz, San Andrés Tlalnehuayocan, 19°31'00.0"N, 97°00'25.4"W. 1500 m. Fragmented cloud forest. Sifted leaf litter, Winkler extractor. 13.VI.2012. Leg. F. Alvarado & R. Madrigal" (1 male: IEXA).

Distribution.

Mexico: Veracruz (Fig. 21).