Macrocheilus assmanni Serrano 2023, n. sp.
Creators: name: Serrano, Artur R. M.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Macrocheilus
Macrocheilus assmanni

description: Macrocheilus assmanni n. sp.
Figs. 1a, 2a, 4a
Type material. Holotype female: “ Tanzania, 12-17.XII.1996 \ Ruvuma, near Songea\ leg. Werner & Lizler” \\ “Collection\ Th. Assmann \ Bleckede, CAB” (yellow label)\\ Holotype female\ Macrocheilus assmanni n. sp. \ A. Serrano det. 2022 [h] [red card].
Differential diagnosis. Head, pronotum, elytra and legs (except tarsi) black; antennae, distal half of mandibles, palps and tarsi reddish-brown coloured; anterior sub marginal and anterolateral surfaces of pronotum rugose-punctured; elytra without patches; shiny and pubescent.
Description. Length of the holotype: 7.7 mm.
Head (Fig. 1a). Wider than long; length 1.44 mm; width 1.98 mm. Coarsely and deeply punctate, less dense in middle of the frons, each puncture with a long and fine brown-yellowish seta, without microsculpture; last maxillary palpomere slightly dilated, pubescent; eyes prominent, temples short with rows of large setae along hind margin of eyes. Clypeus less densely punctate, each puncture with a long and fine brown-yellowish seta, anterior half with a row of eight large setiferous punctures near the anterior margin. Labrum smooth, wider than long (length 0.77 mm, width 0.91 mm), anterior half rounded along margins, middle sides subparallel, posterior 1/3 sides converging to the base; at the widest point a large seta at each side near the rim, two major discal setae and two anterior marginal setae near the apex (Fig. 2a). A pair of supraorbital setae on each side. Mentum with a central tooth, acuminate and sharp. Antennae with the first and third antennomeres almost cylindrical, the second and fourth antennomeres subpyriforms, the remaining ones depressed, slightly longer than wide, with a thin median longitudinal smooth area; last antennomere more or less acuminate.
Thorax. Pronotum cordiform (Fig. 1a), transverse, 1.6 times wider than long (length 1.22 mm; width 1.95 mm); surface covered with coarse punctures, each bearing one long and fine brown-yellowish seta, intervals smooth; anterior submarginal and anterolateral surfaces rugose-punctate, forming irregular meshes; anterior angles rounded, anterior margin arcuate; posterior margin arcuate in the middle, slightly oblique sinuate towards the posterior angles which are obtuse-rounded and bear a long seta; lateral margins sinuate just anterior to posterior angles, a lateral long seta near the widest part of pronotum, anterior angles with some large bristles; anterior transverse sulcus distinct, pronotal base with a pair of large foveae separated by a median faint sulcus reaching the posterior margin. Scutellum triangular, with scattered setiferous punctures. Prosternum coarsely punctured, without microsculpture.
Elytra (Fig. 1a) subparallel-sided, 1.8 times longer than wide (length 5.08 mm, width 2.85 mm), widening slightly towards the posterior third, not covering the last tergite; only seven striae visible, well-marked and punctured, not reaching the base and the apex; intervals slightly convex, two rows of coarse setiferous punctures close to striae, pubescence sub-erected and directed posteriad; lateral margin rounded in the shoulders, ending in deep furrow densely punctuated towards the scutellum. Scutellar striae slightly punctured and visible between the two rows of first interval. Umbilicate series with about 20 pores, slightly separated in the middle (14+6), apex with 4 extra pores, each in the lengthening of 7 th, 6 th, 5 th and 4 th striae; apical transparent membrane extending from sutural angle to the lengthening of the imaginary 8 th interval.
Legs blackish, knees and tarsomeres reddish-brown coloured; all tarsomeres pubescent, first three fore tarsomeres not dilated, fourth tarsomere triangulate; fore tibiae without blunt spines in the outer margin.
Ventral surface. Almost all underside blackish, posterior margins of abdominal sternites red-brownish; whole underside, including abdominal sternites coarsely punctured and pubescent (yellowish color), except gula and ventral and lateral sides of neck. Pubescence of prosternum and proepisternum sub-erected and slightly directed anteriad; pubescence of the remaining ventral sclerites dressed and directed posteriad. Elytral epipleura moderately punctured, pubescence dressed and directed posteriad.
Female genitalia (Fig. 4a). Gonocoxite 1 subtriangular; gonocoxite 2 short, largely sickle shaped, apex short and sharp; dorsal surface concave, strongly setose, inner margin with 1 seta; ventral surface convex, smooth.
Male. Unknown.
Etymology. This species is named in honour of Professor Thorsten Assmann (Leuphana University, Lüneburg, Germany), a well-known carabidologist.
Remarks. The new species is akin to Macrocheilus alluaudi Burgeon, 1937 by the black body colour (Figs. 1f, 1g), differing from this species by the smaller size and shape of last maxillary palpomere and labrum, among other external morphological characters. This slender and small new species differs from the remaining African species by the totally black body colour, with absence of yellow/orange elytral spots or bands, and by the distal surface of pronotum strongly rugose-punctuated, forming irregular meshes.
Distribution. Only known from Tanzania.
description: Published as part of Serrano, Artur R. M., 2023, Afrotropical ground beetles of Macrocheilus Hope, 1838 (Coleoptera, Carabidae) description of four new species and faunistic notes, pp. 1-35 in Zootaxa 5256 (1) on pages 2-3, DOI: 10.11646/zootaxa.5256.1.1, http://zenodo.org/record/7745281