Ptomaphaginus Portevin, 1914

Wang, Cheng-Bin & Zhou, Hong-Zhang, 2015, Taxonomy of the genus Ptomaphaginus Portevin (Coleoptera: Leiodidae: Cholevinae: Ptomaphagini) from China, with description of eleven new species, Zootaxa 3941 (3), pp. 301-338 : 303

Genus Ptomaphaginus Portevin, 1914

Portevin, 1914a: 194 (species included: longitarsis ); Jeannel, 1936: 54 (characters; key to species); Szymczakowski, 1964: 66 (phylogeny; key to species; revision); Perreau, 2000: 370 (world catalog; 72 species).

Type species: Ptomaphaginus longitarsis Portevin , by monotypy.

Synonymy. Euptomaphagus Hatch, 1928: 158 (Type species: Ptomaphagus cilipes Portevin , by original designation); Jeannel, 1936: 54 (synonym with Ptomaphaginus ).

The members of this genus can be distinguished from all other genera within the tribe Ptomaphagini by the combination of the following characters (according to Jeannel, 1936; Szymczakowski, 1964; Peck, 1973; Newton, 1998; Gnaspini, 1998; Perreau, 2000): (1) size small, 1.8–3.5 mm; (2) compound eyes always present; (3) pronotum with transverse striolations, interspaces generally narrower than that on elytra, widest at hind corners of base ( Figs. 1 A; 2A); (4) male basal three protarsomeres expanded; (5) protibiae of fossorial type, with distinct comb of short spines along outer margin as well as around apex; (6) mesepimera transverse, as wide at inner margin as at outer margin, anterior lateral margin straight, and posterior lateral corner pointing posteriorly; (7) mesosternal medial carina relatively low; (8) metasternal lateral carinae almost parallel to each other and to the axis of the body; (9) winged or wingless; (10) spiculum gastrale with anterior margin aligned with that of genital plates; (11) aedeagus subcylindrical, broad and short, stout in most species, sometimes more or less slender and flattened, apex variable in shape, genital orifice on ventral surface or cutting right margin of median lobe in shift to dorsal surface.

Some other morphological characters had also found to be of taxonomic significance: Mouthparts. Labrum transverse, anterior margin rounded; epipharyngeal area with torma ( Figs. 1 B; 2B). Left and right mandibles distinctly asymmetrical, each with a tooth on inner margin of subapex; subapical orthogonal penicillus made up of slender, fine and dense setae ( Figs. 1 C, D; 2C, D). Maxillary palp only penultimate palpomere wholly covered with setae, length more than twice its width, and slightly swollen towards apex; ultimate palpomere quite slender, feebly arched, a little shorter than penultimate palpomere, base slightly thickened, apex narrowly rounded ( Figs. 1 E; 2E). Hypopharynx and labial palps as shown in Figs. 1 F; 2F, premier labial palpomere about as long as succeeding two palpomeres together. Cervical sclerites. Cervical sclerites with end acuminate, pistol-like ( Fig. 1 G). Thorax. Prosternum with integumental foramina (where prolegs inserted) widely separated ( Fig. 1 I). Meso- and metasternum as shown in Fig. 1 K, mesosternal apophysis strongly developed, edge somewhat thickened. Metatergal apparatus generally broad ( Fig. 1 J). Metendosternite with wide furcal arms ( Fig. 1 H).

Figures

FIGURE 1. Ptomaphaginus gutianshanicus sp. nov. ♂: A, extended habitus (dorsal view); B, labrum (dorsal view); C, left mandible (dorsal view); D, right mandible (dorsal view); E, right maxilla (dorsal view); F, hypopharynx and labial palps (ventral view); G, cervical sclerite (dorsal view); H, metendosternite (dorsal view); I, prothorax (ventral view); J, metatergal apparatus (dorsal view); K, pterothorax (ventral view). Scales: A = 1 mm; B – K = 0.1 mm.