Octavius gxalingengwanus 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 : 512-514

Octavius gxalingengwanus Janák , sp. nov.

( Figs. 85–91 , 121 , 134 )

Type locality. South Africa, KwaZulu-Natal Province, Maloti-Drakensberg Park, Mkomazi Wilderness area, Gxalingenwa forest .

Type material (27 specimens). Holotype ♂: “ South Africa, KwaZulu-Natal, Maloti-Drakensberg Park, Mkomazi WA; Gxalingenwa forest ; 29°39.2ʼS 29°25.2ʼE 1610m; 15.i.2019, J. Janák lgt.”, “Berlese extraction, leaf & log litter, sifting”, “ HOLOTYPUS Octavius gxalingengwanus sp. nov. J. Janák det. 2021” ( TMSA) . Paratypes: 9 ♂, 17 ♀: same data as holotype ( TMSA, JJRC). All paratypes with additional labels: “ PARATYPUS Octavius gxalingengwanus sp. nov. J. Janák det. 2021”.

Description. Body length 0.9–1.1 mm (M 1.02 mm, HT 1.0 mm), forebody length 0.4–0.5 mm (M 0.43 mm, HT 0.4 mm). Microphalmous, apterous, rusty, slightly shiny ( Fig. 85 ).

Head ( Figs. 86–87 ) slightly broader than pronotum (R 1.02–1.12, M 1.06, HT 1.09), eyes represented only by one ommatidium ( Figs. 86–87 , o), sides of head slightly widened towards posterior angles, posterior angles moderately angular, median impression on disc absent, surface with very fine reticulation consisting of irregular polygonal fields and very fine punctures raising from center of each field.

Pronotum ( Figs. 86–87 ) markedly longer than broad (R 1.16–1.27, M 1.20, HT 1.19), 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. 86–87 ) roundly trapezoid, markedly broader than long (R 1.15–1.33, M 1.24, HT 1.18), about as broad as head (R 0.94–1.06, M 0.99, HT 0.94), 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. 90 ),sternite IX as in Fig.91 .Aedeagus symmetrical, small, relatively short and wide (length 0.14–0.16 mm, M 0.15 mm, HT 0.13 mm), apical part weakly sclerotized, pointed, apical part with pair of moderately long internal structures, middle part with a narrow moderately long internal structure, internal sac apically with dense scales; parameres slightly shorter than median lobe, each with very short and moderately robust seta directly at apical point and oriented proximally and 2 finer, longer and narrower setae situated nearby at lateral sides and oriented laterally ( Figs. 88–89 ).

Differential diagnosis. Octavius gxalingengwanus 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 derived from the type locality, Gxalingengwa forest.

Distribution. Octavius gxalingengwanus Janák , sp. nov. is currently recorded only from the Gxalingengwa forest in the Mkomazi Wilderness area, Drakensberg Mts., KwaZulu-Natal province, South Africa ( Fig. 121 ).

Bionomics. All specimens were collected in siftings of litter in an indigenous forest patch at the elevation of about 1600 m a.s.l. with the abundance 2.1 specimens per kg of sifted material ( Fig. 134 ).

Figures

FIGURES 85–98. 85–91: Octavius gxaligengwanus Janák, sp. nov.; 85–88, 90–91, holotype; 89, paratype. 92–98: Octavius monachicullus Janák, sp. nov.; 92–95, 97–98, holotype; 96, paratype, Injisuthi. 85, 92, habitus; 86, 93, fore parts; 87, 94, fore parts lateral; 88–89, 95–96, aedeagus ventral; 90, 97, male sternite VIII; 91, 98, male sternite IX. Scale 0.5 mm: 85, 92; scales 0.1 mm: 86–87, 93–94; 88–89, 95–96; 90–91, 97–98; o: ommatidium.

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 134–135. 134: Gxalingenwa forest. 135: Portable Berlese funnels.