Anaxius bloubergensis, Kamiński & Schoeman, 2018

Kamiński, Marcin J. & Schoeman, Colin S., 2018, Taxonomic revision of a darkling beetles genus Anaxius (Tenebrionidae: Pedinini: Helopinina), Zootaxa 4455 (3), pp. 471-485 : 473-475

Anaxius bloubergensis sp. nov.

http://zoobank.org/urn:lsid:zoobank.org:act:81D10A96-9238-4501-AF69-048DFF06453F

( Figs. 1A , 2E, F , 3A , 5 )

Type data. Holotype, male ( TMSA): “ S. Afr.; Limpopo Prov. / Blouberg Nat. Res. / 22.59 S – 29.08 E ”, “25– 27.11.2016 E-Y:3987 / day, sandy bushveld / leg. Ruth Müller ” . Paratypes, 3 males ( TMSA): same data as holotype ; male ( TMSA) and male ( MIZ PAN): “ S. Afr.; Limpopo Prov. Blouberg NR North / dd22 98S, dd 29.12E ”, “ 6.12.2012; 866m, BLN1 / Roodeberg Bushveld / leg. Colin Schoeman ”; male ( MIZ PAN): “ Blouberg NR / Rodeberg Bushveld / -22.98; 29.12”, “leg. Colin Schoeman / BLN7c / I”.

Etymology. The name refers to the type locality, Blouberg Nature Reserve (Limpopo, South Africa).

Diagnosis. This species is distinguished from all other congeners by a unique structure of pro- (first tarsomere extremely widened, following tarsomeres narrow; Fig. 1A ), mesotarsi (first tarsomere widened; Fig. 2F ), mesotibiae (flattened laterally; protruding outwards apically; Fig. 2F ), and aedeagal tegmen (without basal gap; Fig. 3A ).

Description. Body—length = 8.0-9.0 mm. Habitus as in Fig. 1A .

Dorsal side of head covered with fine confluent punctures (0.5–1.0 diameters apart). Frontoclypeal suture rough. Canthus rounded at base; narrower than head at level of eyes. Clypeal emargination shallow (clypeal emargination width: depth ratio ca. 8.0). Labrum narrow (width: length ratio ca. 1.1); strongly emarginate medially; with basal membrane exposed. Ligula exposed, not covered by mentum. Mentum widest in apical part; with well-developed medial keel; with exposed lateral lobes; not covering cardo or basistipes; apically with median indentation. Submentum pentagonal; short. Apical segment of maxillary palpus trapezoidal; with sensory field occupying whole proximal edge. Second segment of maxillary palpus elongate (length: width ratio ca. 2.4). Palpifer located laterally on basistipes. Anterior tentorial pit circular. Eye not dorsally shielded by any keel. Margin between maxillary fossa and antenna insertion well marked. Antenna relatively long (antenna: pronotum length ratio ca. 1.4); third antennomere short (3rd: 2nd antennomere length ratio ca. 3.0); fifth antennomere elongated (length: width ratio ca. 2.0).

Pronotum narrower than elytra (elytra: pronotum width ratio ca. 1.3); relatively narrow (length: width ratio of pronotal disc ca. 0.7); disc dull, covered with fine punctures (3–4 diameters apart). Lateral sides of pronotal disc straight. Disc widest in basal half; without apophyseal depressions. Basal and lateral emargination of pronotal disc present; anterior interrupted in middle. Base of pronotum straight. Posterior angles not protruding beyond base. Pronotal hypomeron dull; without punctures; covered with very fine longitudinal rugosities; without submarginal indentation. Intercoxal process of prosternum depressed apically (lateral view); apically with oval depression on ventral surface; slightly protruding towards first abdominal segment. Procoxae narrowly separated (procoxa: intercoxal process width ratio ca. 2.0).

Elytral striae and intervals not clearly visible. Elytron covered by shiny tubercles (0.1 diameters apart) displayed on dull surface. 1st, 3rd, 5th and 7th intervals protruding on disc; transforming into sparsely (1–2 diameters apart) distributed, large, tubercles on elytral apex. Elytral base straight; not emarginate. Elytral humerus rounded. Epipleuron slightly narrowing apically, then of constant width; basally covering all elytral intervals (ventral view). Scutellum relatively large; triangular. Metathoracic wings absent.

Metaventrite extremely short (metacoxal cavity: metaventrite (between insertions of meso- and metacoxae) length ratio ca. 10.0). Process of first abdominal ventrite wide (distances between mesocoxae: metacoxae ratio ca. 0.9). Fifth abdominal ventrite without submarginal sulcus; covered with fine punctures (4–5 diameters apart).

Male pro- and mesotarsi with basal tarsomere widened. Protibia with deep longitudinal cavity. Profemora simple. Mesotibiae flattened laterally; protruding outwards apically. Mesofemora with internal extension in apical part. Metatibia and metafemora with fringe of setae distributed on whole length. Metatibia curved inwards. First tarsomere of metatarsi elongated (1.5× longer than 4th one). Length of metatarsus equal to half of metatibial length.

Aedeagal tegmen widest in middle; unipartite; without basal gap. Apical part divided (up to 0.15 of whole tegmen length). Clava straight. Penis of even width along most of its length; with apical part not covered by tegmen, exposed dorsally. Basal apophyses of penis relatively short (ca. 0.4 of whole tegmen length).

Distribution. This species has been collected in the following ecoregions of South Africa ( Fig. 5 ): Drakensberg montane grasslands, woodlands and forests; and Southern African bushveld.

Figures

FIGURE 1. Habitus images of the studied species. Anaxius bloubergensis (A), A. campbellae (B), A. limpopoensis (C), A. meletsensis (D), A. obesus (E), A. prozeskyi (F), and A. pseudoloensus (G).

FIGURE 2. Diagnostic characters proposed for Anaxius: mentum (A), proleg (B, G), mesoleg (C, F), metaleg (D), metaventrite (H, I). Anaxius bloubergensis (E, F), A. campbellae (A, H), A. meletsensis (G, I), and A. prozeskyi (B, C, D). Abbreviations: d—denticles, ld—surface between labial palpi, lk—longitudinal keel, lw—lateral wing, p—palpifer, t—apical denticle, tub—tubercles.

FIGURE 3. Aedeagal tegmen morphology. Anaxius bloubergensis (A), A. campbellae (B), A. limpopoensis (C), A. meletsensis (D), and A. pseudoloensus (G).

FIGURE 5. Distribution of the species representing Anaxius.