Cephennodes (Cephennodes) letheanus, Jałoszyński, 2017

Jałoszyński, Paweł, 2017, Ant-like stone beetles on the roof of the world. Cephenniini of Nepal and Bhutan (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4349 (1), pp. 1-120 : 54-55

Cephennodes (Cephennodes) letheanus sp. n.

( Figs 148. 163–166 , 223 )

Type material. Holotype: NEPAL (Mustang District): ♂, one label: " Nepal 435 Mustang Distr.,right / banks of Lethe Khola near / Lethe, 2400 m, 5.–7.V.1995 / MARTENS & SCHAWALLER" [white, printed] ( SMNS).

Diagnosis. BL 1.23 mm; abdominal sternite III in ventral view with basal transverse carina expanded posteriorly at middle and forming here rounded lobe, and with posterior median projection which is subtriangular with rounded sides and pointed apex; apex of median lobe of aedeagus rounded; apical projection of aedeagus partly hidden behind median lobe, with distal margin nearly straight and transverse in relation to the long axis of aedeagus.

Description. Body of male ( Fig. 148 ) dark brown, weakly constricted between pronotum and elytra, strongly convex, covered with light brown setae; BL 1.23 mm.

Head subtrapezoidal, HL 0.15 mm, HW 0.30 mm; vertex and frons confluent, evenly and relatively strongly convex; supraantennal tubercles small and weakly elevated; eyes large, strongly convex, coarsely faceted. Punctures on central portion of frons small but sharply marked and distinct, separated by spaces 1–1.5 × as wide as diameters of punctures, posteriorly punctures become gradually smaller and sparser; setae sparse, short, suberect. Antennae moderately long, compact, moderately thickened, pentamerous club indistinctly delimited; AnL 0.65 mm; antennomere I twice as long as broad; II similar in length but slightly narrower than I, 2.3 × as long as broad; III–VI subequal in length and width, each slightly narrower than II and 1.2–1.3 × as long as broad; VII slightly broader and distinctly longer than VI, 1.2 × as long as broad; VIII as long as VII but distinctly broader, about as broad as long; IX much broader and longer than VIII, as long as broad; X slightly larger than IX, as broad as long; XI distinctly broader than X but shorter than IX–X together, about 1.7 × as long as broad.

Pronotum in dorsal view nearly semicircular, broadest near middle, PL 0.38 mm, PW 0.58 mm; anterior margin broadly rounded; lateral margins indistinctly microserrate, rounded, in posterior half distinctly convergent toward nearly right-angled hind corners; posterior margin distinctly bisinuate; lateral carinae narrow, fused with lateral margins; antebasal pits small and shallow, each nearly equally distant from posterior and lateral margin of pronotum. Punctures on disc very small and shallow, evenly and densely distributed, separated by spaces 1–1.5 × as wide as diameters of punctures; setae moderately dense, short, suberect.

Elytra short, oval, broadest slightly anterior to middle, EL 0.70 mm, EW 0.64 mm, EI 1.10. Humeral calli weakly elevated; subhumeral line on each elytron with small pit at base, equal in length to about 0.3 EL, nearly parallel to elytral suture and developed as a sharp stepwise border between more convex humeral region and less convex adsutural area; basal pit on each elytron large and connected to short, distinctly arcuate impression extending posteromesally; apices of elytra separately rounded. Punctures slightly more distinct than those on pronotum but still very fine, dense; setae short, moderately dense, suberect.

Hind wings present, long.

Metaventrite with large, moderately distinctly delimited postmesocoxal impressions, with median area covered with fine punctures.

Abdomen ( Figs 163–164 ) with only sternite III modified, in ventral view sternite III bears broad transverse carina along its posterior margin, median portion of carina rapidly expanded posteriorly and forming a rounded lobe, posteriorly sternite III with subtriangular median projection with rounded sides and pointed apex.

Legs unmodified.

Aedeagus ( Figs 165–166 ), slender, AeL 0.18 mm, apex of median lobe rounded; apical projection partly hidden behind median lobe, its distal margin nearly straight and transverse in relation to the long axis of aedeagus; parameres very slender, unequal in length, not exceeding apex of median lobe, each with one apical seta.

Female. Unknown.

Distribution ( Fig. 223 ). Central Nepal.

Etymology. Locotypical; after the Lethe River.

Remarks. This species differs from all members of the C. simplicipes group in the apical projection of aedeagus, which has its apical portion slightly curved proximally and its distal margin is transverse to the long axis of the aedeagus. The Chinese species C. simplicipes ( Jałoszyński, 2007b; Figs. 63–65) has slightly similar aedeagus, but the median lobe and the apical projection have clearly different shapes. Moreover, these two species can easily be distinguished on the basis of the abdominal sternites, which in C. letheanus are modified in a much more complicated way. The sternite III in C. simplicipes is only projected ventrally and bears neither the basal carina nor the posterior projection ( Jałoszyński, 2007b; Fig. 62). Among Himalayan species, modifications of the sternite III are sufficient to distinguish C. letheanus from all its congeners.

Figures

FIGURES 148 – 155. Dorsal habitus of Cephennodes (s. str.) letheanus sp. n. (148), C. (s. str.) myagdiensis sp. n. (149), C. (s. str.) malla sp. n. (150), C. (s. str.) gorkha sp. n. (151), C. (s. str.) tharepatianus sp. n. (152), C. (s. str.) minisulcatus sp. n. (153), C. (s. str.) mustangensis sp. n. (154), and C. (s. str.) lalitpuranus sp. n. (155).

FIGURES 156 – 162. Dorsal habitus of Cephennodes (s. str.) paralalitpuranus sp. n. (156), C. (s. str.) bahrabisensis sp. n. (157), C. (s. str.) bilaminatus sp. n. (158), C. (s. str.) ghorepanianus sp. n. (159), C. (s. str.) cordilaminatus sp. n. (160), C. (s. str.) mangmayanus sp. n. (161), and C. (s. str.) bilobatus sp. n. (162).

FIGURES 163 – 178. Abdomen of male in right lateral (163, 167, 171, 175) and ventral (164, 168, 172, 176) views and aedeagus in ventral (165, 169, 173, 177) and lateral (166, 170, 174, 178) views. Cephennodes (s. str.) letheanus sp. n. (163 – 166), C. (s. str.) myagdiensis sp. n. (167 – 170), C. (s. str.) malla sp. n. (171 – 174), C. (s. str.) gorkha sp. n. (175 – 178).

FIGURES 223 – 224. Distribution of Cephennodes (s. str.) letheanus sp. n. (223, circle), C. (s. str.) myagdiensis sp. n. (223, triangle), C. (s. str.) malla sp. n. (224, circle), C. (s. str.) gorkha sp. n. (224, circle).