Octavius subulatus 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 : 515-517

Octavius subulatus Janák , sp. nov.

( Figs. 107–112 , 121 , 126–128 )

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

Type material (26 specimens). Holotype ♂: “ South Africa , KwaZulu-Natal, Maloti-Drakensberg Park, Cathedral Peak NR, Rainbow Gorge, 28°57.6ʼS, 29°13.4ʼE, 1500m, 4.i.2019, J. Janák lgt., Berlese extraction, leaf & log litter, sifting”, “ HOLOTYPUS Octavius subulatus sp. nov. J. Janák det. 2021” ( TMSA) . Paratypes: 2 ♀: same data as holotype ( TMSA, JJRC) ; 6 ♂: “ South Africa, KwaZulu-Natal, Maloti-Drakensberg Park, Cathedral Peak NR, Oqualweni Fern forest ; 28°56.6ʼS, 29°11.0ʼE, 1570m, 7.i.2019, J. Janák lgt., Berlese extraction, leaf & log litter, sifting” ( TMSA, JJRC) ; 2 ♂, 4 ♀: “ South Africa, KwaZulu-Natal, Maloti-Drakensberg Park; Cathedral Peak NR, Masongwane r. banks , 28°58.2ʼS, 29°14.7ʼE, 1600m, 21.xi.2021, J. Janák lgt.” ( TMSA, JJRC) ; 6 ♂, 5 ♀: “REP. SOUTH AFRICA: Natal Cathedral Peaks For. Sta. , 75 km WSW Estcourt, 7-31.XII.1979, S&J Peck”, “Ber 12, 19.XII.1979, Podocarp For., 1500m, litter at base of buttress roots” ( FMNH, JJRC) . All paratypes with additional labels: “ PARATYPUS Octavius subulatus sp. nov. J. Janák det. 2021”.

Description. Body length 1.0– 1.2 mm (M 1.05 mm, HT 1.13 mm), forebody length 0.4–0.5 mm (M 0.46 mm, HT 0.45 mm). Microphalmous, apterous, rusty, slightly shiny ( Fig. 107 ).

Head ( Figs. 108–109 ) slightly broader than pronotum (R 1.03–1.11, M 1.08, HT 1.11), eyes represented only by one ommatidium ( Figs. 108–109 , 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 polygonal fields and very fine punctures raising from center of each field.

Pronotum ( Figs. 108–109 ) markedly longer than broad (R 1.13–1.33, M 1.22, HT 1.17), 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. 108–109 ) roundly trapezoid, markedly broader than long (R 1.11–1.29, M 1.18, HT 1.18), about as broad as head (R 0.90–1.01, M 0.97, HT 0.95), 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 largely rounded ( Fig. 112 ), sternite IX as in Fig. 113 . Aedeagus symmetrical, moderately long and narrow (length 0.15–0.17 mm, M 0.16 mm, HT 0.16 mm), apical part pointed, with long awl shaped internal structure; parameres almost as long as median lobe, with 2 apical and 1 subapical setae ( Figs. 110–111 ).

Differential diagnosis. Octavius subulatus 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 latin word subula (awl), which refers to the shape of the internal structure of the aedeagus.

Distribution. Octavius subulatus Janák , sp. nov. is currently recorded only forests from the Cathedral Peak area (Rainbow gorge, Oqalweni Fern forest, Masongwane river banks), Drakensberg Mts., KwaZulu-Natal province, South Africa ( Fig. 121 ).

Bionomics. All specimens were collected in siftings of litter in indigenous forest patches at the elevation of about 1500–1600 m a.s.l. ( Figs. 126–128 , the abundance of specimens per kg of sifted material: 0.1 in Rainbow gorge, 0.4 in Oqalweni Fern forest and 0.6 on Masongwane river banks).

Figures

FIGURES 99–112. 99–106: Octavius regius Janák, sp. nov.; 99–103, 105–106, holotype; 104, paratype. 107–112: Octavius subulatus Janák, sp. nov.; 107–110, 112–113, holotype; 111, paratype. 99, 107, habitus; 100, 108, fore parts; 101, 109, fore parts lateral; 102, detail of eye with omatidia; 103–104, 110–111, aedeagus ventral; 105, 112, male sternite VIII; 106, 113, male sternite IX. Scale 0.5 mm: 99, 107; scales 0.1 mm: 100–101, 108–109; 103–104; 110–111; 105–106, 112–113. LOR: lateral outer ridge, 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 122–127. 122–123: Golden Gate. 124–125: Royal Natal: 124, Gudu forest, 125, Devilʼs Hoek. 126–127: Cathedral Peak: 126, Rainbow gorge, 127, Oqualweni Fern forest.

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.