Stiptopodius muellerae Daniel & Deschodt, 2020

Daniel, Gimo M., Deschodt, Christian M., Davis, Adrian L. V. & Sole, Catherine L., 2020, The enigmatic dung beetle genus Stiptopodius Harold, 1871 (Coleoptera Scarabaeidae: Scarabaeinae) revisited: new species descriptions from southern Africa, Zootaxa 4763 (3), pp. 394-404 : 400-402

Stiptopodius muellerae Daniel & Deschodt , new species

( Figs. 1C , 2 A–B, 3A, 3C, 4)

Type locality: Caconda, Huila, Angola.

Type material. Holotype, male: Angola, Huila Prov. | 75 km S Kacopnda [Caconda] | 13.24 S – 15. 28 E || 8.11.2011;E-Y: 3916 | sandy forest, 1643m | leg. Ruth Müller || TM SOUTH AFRICA | TMSC13817 || HOLOTYPE: Stiptopodius | muellerae Daniel & Deschodt | 2020 (printed on red card) ( TMSA).

Description. Holotype, male. Length: 7.6 mm, width: 3.8 mm.

Colour. Black.

Head. Incision between medial clypeal teeth deeply concave, lateral clypeal edges not sinuate; external protrusion of genae sharply triangular; surface of head with green sheen; punctation varying from fine to large; setae well-developed except on glabrous anterior clypeal edge; clypeo-frontal carina visible; clypeo-genal suture present; vertex with small medial carina. Antennae with eight antennomeres; labium bears a few well-developed setae.

Pronotum. Convex, wider than long; base of pronotum marginate; anterior margin wider than posterior; in lateral view, lateral edge strongly sinuate before postero-lateral angles, surface with green metallic sheen, ocellate punctation varying from fine to large, each side with small longitudinal tubercle; well-developed setae, except on glabrous central disc.

Elytra. Lateral margin straight, somewhat convex distally and concave proximally, well-developed humeral umbone; striae sparsely and finely punctate. Interstriae punctate, fully setose.

Pygidium. Convex and setose, punctation ocellate.

Abdominal ventrites. Prosternum surface with well-developed setae, anterior angles of prosternum slanted forward and inward. Meso- and metaventrite dull, setose and densely punctate; metaventrite with long setae, surface impressed longitudinally at middle. Abdominal ventrites with ocellate punctures and strong setae arranged in rows laterally, glabrous medially; last abdominal ventrite narrowed medially (male character).

Legs. Profemora sparsely punctate, bearing well-developed setae, external edge strongly marginate, internal margin slightly marginate. Meso- and metafemora with external and internal edges sparsely setigerous and punctate; surface between external and internal margin with few setigerous punctures, strongly marginate in both edges (external and internal). Protibiae crenulate with four teeth on external margin, line of setae around teeth in dorsal view; in ventral view, with two carinae, internally punctate and pilose. Protibial spur long and inward curving. Meso- and metatibiae triangular and strongly widened apically. Protarsi with five tarsomeres and clearly visible pair of claws; fifth protarsomere at least 2x longer than others (each individually). Meso- and metatarsomeres I–IV triangular, longer than wide, with internal line of strong setae on tarsomere I, strongly concave medially, bilobate distally, external lobe strong, internal lobe weak; tarsomere V rectangular and longer than others, followed by pair of very tiny apical claws.

Aedeagus. Parameres symmetrical, elongate with tips acute ( Figs. 2 A–B).

Female. Unknown

Distribution. The species is only known from the type locality, Caconda, Province of Huila, Angola. It was hand collected in sandy forest.

Etymology. The specific name honours Ruth Müller, a friend and curator in charge of Coleoptera at the Ditsong National Museum of Natural History, Gauteng, Pretoria, South Africa, who collected the holotype.

Diagnosis. The new species is somewhat similar to S. singularis by having the basal half of the pronotal disc glabrous and frontal carina obsolete. However, S. singularis bears uniform punctation on the pronotum, with a brown metallic sheen, whereas S. muellerae new species has a distinctive green metallic sheen with punctures of variable sizes ranging from fine to large. The elytra of this new species are fully setose, while those of S. singularis are slightly setose posteriorly and glabrous anteriorly. The mesotibiae are sinuate externally in S. muellerae new species but not in S. singularis . The male genitalia differ between the two species by having the tips of the parameres sharp and projecting forward in the new species ( Figs. 2 A-B), whereas in S. singularis they are short and blunt ( Figs. 2 E-F). S. muellerae new species is also much larger than S. singularis .

Remarks. This is the first record of a Stiptopodius species whose meso- and metatarsomeres I–IV are longer than wide ( Figs. 3A, C ). The first tarsomere is the longest, which is in contrast to the other 5-articulated species, where tarsomere V is longer than others. Furthermore, in S muellerae new species, meso- and metatarsomeres I–IV bear a weak lobe externally.

Conservation status and potential threats. The forest at the type locality is surrounded by lands supporting agricultural and pastoral farming activities (R. Müller, personal communication). It is therefore probably under severe pressure. As this species is only known from this locality, it may warrant the threat category of at least Vulnerable.

Figures

FIGURES 1A–D. Habitus of Stiptopodius Harold, 1871 species, holotypes. A, Stiptopodius peringueyi Daniel & Deschodt, new species; B, Stiptopodius savuti Daniel & Deschodt, new species; C, Stiptopodius muellerae Daniel & Deschodt, new species; D, Stiptopodius singularis (Péringuey, 1901). Scale bar = 2.0 mm.

FIGURES 2A–F. Aedeagi of Stiptopodius Harold, 1871 species in dorsal (A, C, E) and lateral (B, D, F) views. A, B, Stiptopodius muellerae Daniel & Deschodt, new species; C, D, Stiptopodius peringueyi Daniel & Deschodt, new species; E, F, Stiptopodius singularis (Péringuey, 1901). Scale bar = 1.0 mm.

FIGURES 3A–D. Left middle (A, B) and left hind tibiae and tarsi (C, D) of Stiptopodius Harold, 1871 species. A, C, Stiptopodius muellerae Daniel & Deschodt, new species; B, D, Stiptopodius singularis (Péringuey, 1901). Scale bar = 1.0 mm.