Dermestocyphon Pic, 1918

Ruta, Rafał, Yoshitomi, Hiroyuki & Klausnitzer, Bernhard, 2013, Review of the genus Dermestocyphon (Coleoptera: Scirtidae: Scirtinae), Acta Entomologica Musei Nationalis Pragae 53 (1), pp. 253-285 : 257-260

Subgenus Dermestocyphon Pic, 1918

Type species. Cyphon drianti Pic, 1918

Diagnosis. Body elongate, parallel-sided ( Figs 1–6 ); pronotum always yellow to orange, elytra black or with yellow humeral or adsutural portions; segment III of labial palpi arising from lateral part of segment II ( Fig. 20 ); mandibles with long, narrow, and abruptly curved apical portion ( Fig. 18 ); females always with humeral excitators ( Figs 44, 46, 48–51 ), in D. apiciconcavus also with apical excitators ( Fig. 47 ). Sternite VII (♀) without distinct membranous flap ( Fig. 30 ). Concave groove on tergite VII (♀) indistinct ( Fig. 31 ). Bursella with proximal tricornate sclerite and two small oval distal sclerites ( Figs 53, 55, 57 ). Ovipositor with relatively well sclerotized proctiger, which is composed of a pair of thumb-like projections covered with dense setae ( Figs 52, 54, 56 ).

Redescription. Body small to medium, oblong, sides subparallel, covered with semierect setae that are easily broken. Head and pronotum orange, elytra dark brown to black, with yellow to orange maculation.

Head small, labrum transverse, with straight anterior edge, slightly wider than clypeus, which is short and has straight anterior margin. Eyes relatively small, distance between bottom edge of eye and genal ridge ca. 1/9 diameter of eye; antennomeres II and III ca. 1/2 length of antennomere I, which is as long as antennomere IV; segment 3 of labial palpi arising from side of segment 2; galea with irregularly arranged setae; mandibles triangular, with long, abruptly curved apical portion which is gradually narrowing towards apex, inner edge without teeth.

Pronotum small, about 70 % of maximum width of elytra, about 1.9–2.2 times as wide as long, anterior angles subtly projecting forward, posterior angles almost obtuse to sharp, sides rounded, basal margin bisinuate, with complete margination. Elytra without raised longitudinal carinae, sides subparallel, punctures stronger than on pronotum, epipleura relatively wide, gradually narrowing towards the apex. Pronotal process small, narrow, reduced, rod-like; mesoventral notch for reception of prosternal process absent; mesoventral process long, narrow, apex widened, tempered; metaventral discrimen complete.

Male tergite VIII broad, apical portion well sclerotized, covered with sparse setae, apodemes short; tergite IX membranous with weakly sclerotized plate and relatively long apodemes; sternite IX trapezoidal, with setae on apical portion. Tegmen small, weakly sclerotized, Ushaped with long lateral rods. Penis with narrow parameroids, trigonium broadly triangular, with pointed or excised apex, basal margin of pala shallowly or deeply excised.

Female with distinct humeral excitators on elytra, which are more or less concave, but always present on outer margin, and sometimes extending to epipleural portion. Sternite VII without distinct membranous flap; tergite VII with indistinct groove; ovipositor long, coxites narrow, membranous, styli short, apical; proctiger well sclerotized, proximal bursellar sclerite with tricornate anterior margin, distal portion of bursella with paired sclerites.

Key to species

1. Femora and tibiae black ( Figs 1–2 ); posterolateral angles of pronotum (especially in ♀) projecting posteriorly ( Figs 38, 39 ); elytra (♀) with both humeral and apical excitators ( Figs 44–47 ); humeral concavities present in humeral angles. ........... D. apiciconcavus sp. nov.

– Femora and tibiae evenly yellowish to orange ( Figs 3–6 ); posterolateral angles of pronotum obtuse ( Figs 40–43 ); apical excitators on ♀ elytra absent. ............................................ 2.

2. Elytra uniformly dark brown to black ( Figs 3–4 ); parameroids of penis distinctly longer than trigonium ( Fig. 67 ); elytra (♀) with very shallow humeral excitators ( Figs 48, 49 ); antennomere IV yellow. ................................................................ D. drianti ( Pic, 1918)

– Elytra black with yellow humeral portions (rarely elytra unicolored in ♂) or yellow adsutural region (in ♀) ( Figs 5, 6 ); parameroids of penis only slightly longer than trigonium ( Figs 72–73 ); female with deep and concave humeral excitator ( Figs 50, 51 ); antennomere IV black. .......................................................................................... D. suturalis sp. nov.

Figures

Figs 1–6. Habitus of Dermestocyphon (Dermestocyphon): 1 – D. apiciconcavus sp. nov., holotype, male; 2 – ditto, paratype, female; 3 – D. drianti (Pic, 1918), holotype, male and labels; 4 – ditto, female; 5 – D. suturalis sp. nov., paratype, male; 6 – ditto, female. Scale bar = 1.0 mm.

Figs 18–26. Mouthparts of Dermestocyphon (males); 18, 21, 24 – mandible; 19, 22, 25 – maxilla; 20, 23, 26 – labium: 18–20 – D. drianti (Pic, 1918); 21–23 – D. optatus (Klausnitzer, 1980); 24–26 – D. niisatoi sp. nov.

Figs. 44–51. Excitators of females of D. apiciconcavus sp. nov. (44–47), D. drianti (Pic, 1918) (48–49), and D. suturalis sp. nov. (50–51): 44, 46, 48–51 – Humeral area in lateral view; 45, 47 – apex of elytra in lateral (45) and caudal (47) view.

Figs 30–37. Last visible sternite (30, 32, 35), membranous flap (33, 36) and tergite VII (31, 34, 37) of female: 30–31 – D. suturalis sp. nov.; 32–34 – D. honorus (Klausnitzer, 1980); 35–37 – D. optatus (Klausnitzer, 1980).

Figs 52–58. Dermestocyphon (Dermestocyphon) spp., female genitalia: ovipositor (52, 54, 56), bursella (53, 55, 57), and distal bursellar sclerite (58): 52–53 – D. apiciconcavus sp. nov.; 54–55 – D. drianti (Pic, 1918); 56–58 – D. suturalis sp. nov.

Figs 38–43. Pronotum of male (38, 40, 42) and female (39, 41, 43): 38–39 – D. apiciconcavus sp. nov.; 40–41 – D. drianti (Pic, 1918); 42–43 – D. suturalis sp. nov.

Figs 63–67. Dermestocyphon (Dermestocyphon) drianti (Pic, 1918), male genitalia: 63 – sternite IX; 64 – tergite VIII; 65 – tergite IX; 66 – tegmen with lateral projections; 67 – penis. Scale bar = 0.5 mm.

Figs 68–73. Dermestocyphon (Dermestocyphon) suturalis sp. nov., male genitalia; specimen from Laos (68–72) and from Myanmar (73): 68 – sternite IX; 69 – tergite VIII; 70 – tergite IX; 71 – tegmen with lateral projections; 72–73 – penis. Scale bar = 0.5 mm.