Epistomius natalensis, Borovec & Skuhrovec, 2017

Borovec, Roman & Skuhrovec, Jiří, 2017, Epistomius, a new genus of African forest litter Trachyphloeini, with descriptions of seven new species (Coleoptera: Curculionidae: Entiminae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 57 (2), pp. 645-676 : 663-666

publication ID

https://doi.org/ 10.1515/aemnp-2017-0094

publication LSID

lsid:zoobank.org:pub:C3673E78-B076-4FA0-A808-327C772B1CE4

DOI

https://doi.org/10.5281/zenodo.5335405

persistent identifier

https://treatment.plazi.org/id/B32E87D9-AD0D-FFE0-FE19-6684FE42FD77

treatment provided by

Marcus

scientific name

Epistomius natalensis
status

sp. nov.

Epistomius natalensis View in CoL sp. nov.

( Figs 2D–F View Fig , 3D View Fig , 8A–G View Fig )

Type locality. South Africa, KwaZulu-Natal, Umtamwuna Nat. Res., trail from Beacon Hill, 31°01′09″ S 30°16′97″ E, 200–250 m a.s.l., rainforest.

Type material. HOLOTYPE: ♂, ‘ RSA (E) [ South Africa, East], KwaZulu-Natal, 31.0109S / 30.1697E,Umtamwuna Nat. Res., trail from Beacon Hill, 10.11.2013, 200- 250 m, rainforest, sifted litter, leg. M. Wanat’ ( TMSA). PARATYPES: 32 ♂ ♀, the same data as holotype ( MNHW, RBSC).

Additional material examined. 21 ♂ ♀, ‘ South Africa, KwaZulu Natal, Umtavuna Nature Reserve, 31°1.5-6′ S 30°10.1-2′ E, 13.i.2016, J. Janák lgt.’ ( JJRC, JSPC, NMPC, RBSC).

Description ( Figs 2D–F View Fig , 8A–G View Fig ). Body length 2.06–2.41 mm, holotype 2.15 mm. Body dark brownish to blackish, antennae reddish brown, sometimes apical part of scape or club darker, short apical part of tibiae and tarsi yellowish red to reddish brown. Elytra sparsely covered with appressed scales of irregular shape, rounded to angular, some of them with short fringes, 4 across width of one interval, leaving narrow spaces between them. Pronotum and head with rostrum with dense, irregularly shaped scales, subrounded on pronotal disc and head with rostrum, fan-shaped with fringes on lateral pronotal parts, on head and rostrum almost covering integument. Appressed scales on scape, femora and tibiae identical to those on pronotal disc, smaller and sparser. Elytral setae on basal half semiappressed, subspatulate, about as long as half width of one interval, on apical half perpendicularly erect, long and slender, lancet-shaped, somewhat longer than width of one interval, with indistinct concavity just at apex or pointed, 3–4× longer than setae on basal half, distance of two setae on posterior declivity somewhat longer than length of one setae. Pronotum and head with rostrum with setae somewhat shorter than setae on basal half of elytra, sparse, inconspicuous, semierect, subspatulate, setae on interocular space twice as long as the others. Scape, femora and tibiae with short, long-oval semiappressed setae, hardly prominent from outline. Body vestiture light greyish brown.

Head ( Figs 8A–D View Fig ). Rostrum in both sexes ( Figs 8B–C View Fig ) identical, in basal half slightly tapered apicad with straight sides, in apical half indistinctly enlarged around scrobes, not prominent laterally, 1.09–1.15× as wide as long, equally wide at base and at apex, at apex distinctly narrower than head including eyes. Epifrons with distinct longitudinal median stria along whole length, when cleared of scales shiny, smooth, unpunctured, with slender median longitudinal stria, shallowly regularly longitudinally depressed. Frons deepened, smooth. Epistome in both sexes narrow, about equally wide as epifrons at midlength. Head when cleared of scales shiny and smooth, unpunctured, with slender longitudinal fovea. Eyes faintly prominent from outline of head.

Antennae ( Fig. 8A View Fig ). Antennal scape 5.4–6.1× as long as wide and 1.5× as long as funicle, at apex equally wide as club. Funicle segment I 1.5–1.6× as long as wide and 1.7–1.8× as long as segment II, which is 1.2–1.3× as long as wide; segments III–VI 1.4× as wide as long; segment VII 1.3× as wide as long. Club 2.0–2.1× as long as wide.

Pronotum ( Fig. 8A View Fig ) 1.47–1.56× as wide as long, widest behind midlength, with distinctly rounded sides, behind anterior margin weakly constricted. When cleared of scales regularly convex, shiny, moderately densely coarsely punctured, punctures very large, 6–7 along whole length, distance between two punctures about equal to semidiameter of one puncture. Pronotum in lateral view weakly convex, behind anterior border lowered.

Elytra ( Fig. 8A View Fig ) in males 1.15–1.18×, in females 1.17–1.22× as long as wide.

Legs ( Figs 8A, E View Fig ). Tarsomere II 1.5–1.6× as wide as long; tarsomere III 1.4× as wide as long and 1.4–1.5× as wide as tarsomere II; onychium 1.5× as long as tarsomere III.

Male genitalia ( Figs 3D View Fig , 8G View Fig ). Penis somewhat longer than wide, narrowest at base, in apical half distinctly enlarged, almost regularly rounded; laterally almost straight, wide, at apex regularly tapered.

Variability ( Figs 2D–F View Fig ). Width of erect elytral setae varying between very slender and sharply pointed to weakly wider, narrowly dully pointed. But all these types keep the same form – lancet-shaped, and also the same length, mainly in comparison between setae on the disc and posterior declivity. The material from the locality Umtavuna was not included in the type series to conserve the typical characters (see the variability chapter in Epistomius description).

Etymology. Patronymic, named after district Kwa-Zulu-Natal, where the type locality is placed.

Biology. The type material was sifted from native forest litter.

Distribution. South Africa: KwaZulu-Natal ( Fig. 4 View Fig ).

Differential diagnosis. The species is characterized by elytral setae on apical declivity semierect to erect, rostrum in both sexes subparallel-sided with epistome in both sexes equal, as wide as epifrons at midlentgh, and it is similar to E. wanati sp. nov., from which it can be distinguished by the following characters: elytral setae on basal half short, semiappressed, on apical half longer than width of one interval, lancet-shaped, laterally weakly curved, 3–4× as long as setae on basal half; funicle segments 3–5 1.4× as wide as long; club long and slender, 2.0–2.1× as long as wide; and penis slender, longer than wide, widest in apical third, rounded, laterally wide.

TMSA

Transvaal Museum

JSPC

J. Rusek Collection

NMPC

National Museum Prague

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Curculionidae

Genus

Epistomius

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