Octavius undulatus Janák, 2024

Janák, Jiří, 2024, On Octavius from Maloti-Drakensberg and Golden Gate National Parks, South Africa (Coleoptera: Staphylinidae: Euaesthetinae), Zootaxa 5443 (4), pp. 495-522 : 517-518

Octavius undulatus Janák , sp. nov.

( Figs. 113–119, 121 , 133 )

Type locality. South Africa, KwaZulu-Natal Province, Maloti-Drakensberg Park Drakensberg, Kamberg National Reserve .

Type material (4 specimens). Holotype ♂: “ South Africa, KwaZulu-Natal, Maloti-Drakensberg Park , Kamberg NR, ind. forest patches 29°21.85ʼS 29°37.1ʼE, 1820- 40m, 12.i.2019, J. Janák lgt.”, “Berlese extraction, leaf & log litter, sifting”, “ HOLOTYPUS Octavius undulatus sp. nov. J. Janák det. 2021” ( TMSA) . Paratypes: 1 ♂, 2 ♀: same data as holotype ( TMSA, JJRC). All paratypes with additional labels: “ PARATYPUS Octavius undulatus sp. nov. J. Janák det. 2021”.

Description. Body length 1.1–1.3 mm (M 1.19 mm, HT 1.2 mm), forebody length ca. 0.5 mm (M 0.48 mm, HT 0.5 mm). Microphalmous, apterous, rusty, slightly shiny ( Fig. 113 ).

Head ( Figs. 114–115 ) slightly broader than pronotum (R 1.06–1.09, M 1.07, HT 1.07), eyes represented only by one ommatidium, sides of head rounded, posterior angles moderately angular, median impression on disc absent, surface with very fine reticulation consisting of polygonal fields and very fine punctures raising from center of each field.

Pronotum ( Figs. 114–115 ) markedly longer than broad (R 1.16–1.25, M 1.20, HT 1.16), strongly narrowed posteriorly; anterior angles rounded, disc regularly convex, disc and base without impressions, posterior angles shortly rounded; surface finely irregularly reticulate and very finely punctate, similarly as on head.

Elytra ( Figs. 114–115 ) roundly trapezoid, markedly broader than long (R 1.18–1.31, M 1.23, HT 1.22), slightly broader than head (R 1.03–1.06, M 1.04, HT 1.03), with sharp outer longitudinal ridge laterally; surface with very fine reticulation consisting of irregular polygonal fields and then and there with very fine punctures.

Abdomen with two paratergites, with reticulation consisting of polygonal, slightly transverse fields, very finely and sparsely punctate.

Male. Posterior margin of sternite VIII broadly rounded ( Fig. 118 ), sternite IX as in Fig. 119 . Aedeagus symmetrical, long and narrow (length HT, PT 0.24 mm), sides markedly rounded, apical part pointed, internal sac with pair of moderately long curved structures in apical two third and with pair of elongate fields covered by wavy shaped small scales; parameres slightly shorter than median lobe, with 1 apical and 2 subapical moderately long fine setae, all oriented laterally ( Figs. 116–117 ).

Differential diagnosis. Octavius undulatus Janák , sp. nov. belongs among species with one ommatidium together with O. angusticollis Puthz, 2006 and additional four species described in this paper and can be distinguished with certainty only by the shape of the aedeagus and the internal structures – see a key at the end of the description part for details.

Derivatio nominis. The name of this species is the Latin adjective undulatus (= wavy) which refers to the wavy shaped scales in the internal sac of the aedeagus.

Distribution. Octavius undulatus Janák , sp. nov. is currently recorded only from the Kamberg Natural Reserve in Drakensberg Mts., KwaZulu-Natal Province, South Africa ( Fig. 121 ).

Bionomics. All specimens were collected in siftings of forest litter in indigenous forests patches of an indigenous forest at the elevation of about 1820–1840 m a.s.l. with the abundance 0.3 specimens per kg of sifted material ( Fig. 133 ).

Figures

FIGURES 113–121. Octavius undulatus Janák, sp. nov.; 113–116, 118–119, holotype; 117, paratype. 113, habitus; 114, fore parts; 115, fore parts lateral; 116–117, aedeagus ventral; 118, male sternite VIII; 119, male sternite IX. Scale 0.5 mm: 113; scales 0.1 mm: 114–115; 116–117; 118–119; o: ommatidium. 120: Distribution of Octavius – subgroup A. 121: Distribution of Octavius – subgroup B.

FIGURES 128–133. 128: Cathedral Peak, Masongwane river banks. 129: Injisuthi. 130: Monkʼs Cowl, Hlatikulu forest. 131: Lotheni. 132: Kamberg, locality 1. 133: Kamberg locality 2.