Octavius dorsumsuis, Janák, 2014

Janák, JiĜí, 2014, New species and subspecies of Octavius from South Africa, with a key and additional distribution records (Coleoptera: Staphylinidae: Euaesthetinae), Acta Entomologica Musei Nationalis Pragae 54 (1), pp. 195-231 : 206-208

Octavius dorsumsuis sp. nov.

( Figs 23–25 )

Type locality. South Africa, Eastern Cape Province, Hogsback, 32°35ƍS, 26°56–57ƍE.

Type material. HOLOTYPE: 3: ‘ SOUTH AFRICA, Eastern Cape, Hogsback , 32°35ƍS 26°56–57ƍE, 970–1300 m, 5–7.xii.2006, forest litter, sifting, J. Janák leg. // Octavius dorsumsuis sp. n., J. Janák det. 2013’ ( TMSA) . PARATYPES: 343345 ♀♀ (74 spec. in JJRC, 2 spec. in TMSA, 2 spec. in NMPC, 1 spec. in VPSG): same data as the holotype ; 1 3, same data, but ‘ SOUTH AFRICA, Eastern Cape, Hogsback , 32°35ƍS 26°56–57ƍE, 1300 m, 3.ii.2004, sifted litter, P. HlaváÞ leg.’ ( JJRC) .

Description. Body length 1.7–2.4 mm (M 2.2 mm, HT 2.1 mm), forebody length 0.9–1.1 mm (M 1.0 mm, HT 1.0 mm). Macrophthalmous, apterous, reddish brown, head dull, pronotum slightly shiny, elytra and abdomen moderately shiny.

Head distinctly narrower than pronotum (R 0.82–0.88, M 0.84, HT 0.84), eyes moderately large, temples less than twice as long as eyes (R 1.64–1.98, M 1.80, HT 1.88), moderately arcuately widened, median impression on frons absent, lateral parts of head moderately granulose, median part very densely and ¿nely reticulate.

Pronotum distinctly broader than long (R 1.17–1.23, M 1.20, HT 1.18), strongly narrowed posteriorly; anterior angles slightly angular, dorsal impressions shallow, transverse impression deep, lateral impressions deep and delimited by a sharp longitudinal ridge laterally; lateral parts beside lateral impressions densely granulose, lateral, dorsal and transverse impressions sparsely granulose, anterior margin sparsely granulose and sparsely to densely reticulate, remainder of surface densely and deeply reticulate.

Elytra sub-trapezoidal, much broader than long (R 1.63–1.85, M 1.74, HT 1.63), with a sharp longitudinal ridge laterally; irregularly granulate without distinct reticulation.

Male. Aedeagus strongly sclerotised (n = 5, length 0.52–0.57 mm, M 0.55 mm, HT 0.55 mm), with asymmetrical median lobe. Internal structure of aedeagus with a T-shaped sclerotised plate. Parameres enlarged apically, with about 10 setae in apical part ( Fig. 23 ). Sternite 8 broadly emarginate in posterior twelveth ( Fig. 24 ), sternite 9 as in Fig. 25 .

Differential diagnosis. Octavius dorsumsuis sp. nov. belongs among species with large eyes, with the temples at most twice as long as eyes, with the head not or at most slightly widened posteriorly, with the large body size and disc of head without a median impression. It is closely related to O. piriensis ( Kistner, 1967) and O. bulirschi sp. nov., from which it can be distinguished by the anterior part of pronotum sparsely granulate and by shining, sparsely granulate transverse and dorsal impressions and by T-shaped internal structure of aedeagus.

Etymology. This species is named after the type locality: Hogsback (sus = hog and dorsum = back). Noun in apposition.

Bionomics. All specimens have been found in siftings of forest litter in indigenous forest.

Distribution. Octavius dorsumsuis sp. nov. is currently recorded only from Hogsback in Eastern Cape Province, South Africa (for locality picture see JANÁK 2013: Fig. 17 ).

Note. The series from Hogsback was initially considered as comprising variable specimens of O. piriensis by JANÁK (2007: Figs 11–13 , those ¿gures are reproduced here as Figs 23–25 ). In fact, the differences between the series from Hogsback and that from Pirie and Isidenge Forests were con¿rmed by examination of large numbers of specimens. Also the discovery of another related species ( O. multisetosus sp. nov., described below) with a very different internal structure of the aedeagus, and occurring between the distribution area of O. piriensis (Pirie and Isidenge Forest) and O. dorsumsuis (Hogsback) , provides evidence supporting the species-status for the series from Hogsback.

Figures

Figs. 23–28. 23–25 – Octavius dorsumsuis sp. nov., HT male. 26–28 – O. bulirschi sp. nov., HT male. 23, 26 – aedeagus ventral; 24, 27 – sternite 8; 25, 28 – sternite 9. Scale bars = 0.1 mm.

Figs. 17–22. 17–19 – Octavius kogelbergensis sp. nov., HT male. 20–22 – O. zulu sp. nov., HT male. 17, 20 – aedeagus ventral; 18, 21 – sternite 8; 19, 22 – sternite 9. Scale bars = 0.1 mm.

Figs. 10–16. 10–13 – Octavius acutipenis sp. nov., HT male. 14–16 – O. adriani sp. nov., 14, 15 – HT male, 16 – PT male. 10, 14 – aedeagus ventral; 11, 15 – sternite 8; 12, 16 – sternite 9; 13 – apical part of sternite 9. Scale bars = 0.1 mm.