Macrocheilus schuelei, Serrano, 2023

Serrano, Artur R. M., 2023, Afrotropical ground beetles of Macrocheilus Hope, 1838 (Coleoptera, Carabidae) description of four new species and faunistic notes, Zootaxa 5256 (1), pp. 1-35 : 7-12

publication ID	https://doi.org/ 10.11646/zootaxa.5256.1.1
publication LSID	lsid:zoobank.org:pub:CE0AC7CD-E55D-484C-9346-86F16C985DBE
DOI	https://doi.org/10.5281/zenodo.7746797
persistent identifier	https://treatment.plazi.org/id/AE0487C8-F535-FFD3-0986-A6BA6242FF51
treatment provided by	Plazi
scientific name	Macrocheilus schuelei
status	sp. nov.

Treatment

Macrocheilus schuelei n. sp.

Figs. 1d View FIGURE 1 , 2d View FIGURE 2 , 3c View FIGURE 3 , 4c View FIGURE 4

Type material. Holotype male: “ RCA, P.N. Ndoki, Camp 1, Chablis 1,\ 02º 28′ 40.5N 016º 13′ 02.6E, 24–25.II.\ 2012 forêt diversifiée, piège UV. Exp.\ Sangha 12, P. Moretto leg. -117-“ \\ “ Collection P. Sch ̧le, Herrenberg\ Shanga Projekt 2012” \\ “Holotype male\ A. Serrano det. 2022” [t] [h] [red card] GoogleMaps . Paratype: 1 female: “ RCA, P.N. Ndoki, Camp 1, Chablis 1,\ 02º 28′ 40.5N 016º 13′ 02.6E, 20–\ 23.II.2012 forêt diversifiée, piège UV.\ Exp. Sangha 12, P. Moretto leg. -105-“ \\ “Macr-01” (yellow label) ( PSHC) \\ “Paratype female\ A. Serrano det. 2022” [t] [h] [red card] GoogleMaps . Holotype deposited in PSC. Paratype deposited in ASC.

Differential diagnosis. Slender. Head, pronotum, elytrae and abdomen fuscous black or dark brown; labrum, mouthparts, antennae and legs brown; first half of each elytrum with a large longitudinal orange band; shiny, without microreticulation, pubescent.

Description. Length of holotype: 7.0 mm. Length of paratype: 7.4 mm (female).

Head ( Fig. 1d View FIGURE 1 ). Much wider than long (male: length 1.18 mm, width: 1.86 mm; female: length 1.28 mm; width: 1.92 mm). Surface shining, coarsely and deeply punctured, less dense in middle of the frons, each puncture with a long, decumbent and fine brown-yellowish seta, without microsculpture; antero-lateral impressions not marked,

ons not excavated behind clypeus; last maxillary palpomere slightly securiform, pubescent; eyes strongly prominent, temples short, some large setae along posterior margin of eyes. Clypeus almost smooth, anterior half with a row of five submarginal large setiferous punctures. Labrum smooth, dark brown and shiny, 1.1 times wider than long (male: length 0.66 mm, width 0.82 mm; female: length 0.74 mm, width 0.82 mm), anterior half converging, rounded along margins and apex, posterior half lateral margins slightly rounded; a large seta at the widest point near the rim, at the apex 4 setae, two exactly on the margin from the top, and two beneath the margin just on the top ( Fig. 2d View FIGURE 2 ); posterior lateral half up to widest point with a fringe of short setae underneath. A pair of supraorbital setae on each side ( Fig. 1d View FIGURE 1 ). Mentum with a central tooth, acuminate and sharp. Antennae with the first three antennomeres less densely pubescent with rather long setae, from the fourth antennomere densely pubescent with shorter setae, first and third antennomeres almost cylindrical, second and fourth subpyriform, the remaining depressed, slightly longer than wide, with a slight basal thin median longitudinal smooth area; last antennomere more or less acuminate.

Thorax. Pronotum slightly cordiform ( Fig. 1d View FIGURE 1 ), strongly transverse, 1.6 times wider than long (male: length 1.22 mm, width: 1.92 mm; female: length 1.25 mm, width 1.98 mm), maximum width just ahead of the middle length; surface covered with coarsely punctures, more or less uniformly distributed on all areas, bearing each one a long and fine brown-yellowish seta, intervals smooth; anterior angles rounded, anterior margin almost straight; posterior margin straight in the middle, oblique sinuate towards the posterior angles which are rounded and bear a long seta; anterior and posterior margins not margined, lateral margins with complete and distinct margination since the anterior angles, reaching the posterior angles, sinuate just anterior to posterior angles, without forming a tooth before the angles, a long seta in front of the widest part of pronotum, anterior angles with some large bristles; anterior transverse sulcus not distinct, pronotal base with a pair of round faint foveae near the posterior angles, a median slight sulcus in a flat and depressed area that reaches the posterior edge. Scutellum triangular, setiferous punctured. Prosternum coarsely punctured, without microsculpture.

Elytra ( Fig. 1d View FIGURE 1 ) 1.7 times longer than wide (male: length 4.62 mm, width 2.79 mm; female: length 4.88 mm, width 2.94 mm), subparallel-sided, widening slightly towards the posterior third, not covering the last two tergites; only seven striae visible, the first six well-marked, the seventh faint, all slightly punctured and not reaching the base and the apex; intervals slightly convex, without microreticulation, coarse setiferous punctured in two rows on 1 st –7 th intervals, decumbent seta brown-yellowish sub-erected and directed posteriad; lateral margin rounded in the shoulders, ending in deep furrow moderately densely punctured towards the scutellum. Scutellar striae visible between the two row of punctures in the anterior region of first interval. Basal pore present. Umbilicate series with 24 (male) and 29 (female) pores, irregular row in the first half, not interrupted in the middle although they are more separated from each other; 1 subapical pore shifted inward in the lengthening of the imaginary 8 th interval; apex with 4 extra pores, 2 in the lengthening of the imaginary 7 th and 6 th striae, respectively, and 2 in the lengthening of 5 th and 3 rd intervals; apical transparent membrane extending from sutural angle to the lengthening of the imaginary 8 th interval.

The longitudinal sub-humeral orange band extends obliquely from the 6 th to the 2 nd intervals in the anterior region, reaching the intermediate region of the elytra in 3 rd to 5 th intervals ( Fig. 1d View FIGURE 1 ).

Legs. Brown coloured; all tarsomeres pubescent, first three fore tarsomeres not dilated, fourth tarsomere slightly triangulate; fore tibiae on the outer edge with two blunt spines.

Ventral surface. Almost all underside blackish, last abdominal sternite brownish; whole underside, including abdominal sternites coarsely punctured and pubescent (yellowish color), except gula, ventral and lateral sides of neck. Pubescence of prosternum and proepisternum erect; pubescence of the remaining ventral sclerites dressed and directed posteriad. Elytral epipleura moderately punctured, pubescence dressed and directed posteriad.

Male genitalia ( Fig. 3c View FIGURE 3 ). Median lobe dilated in the median region, slightly constricted between basal bulb and shaft, apical margin rounded and slightly acuminated (dorsal view), apex sharp acuminated and downward (lateral view), ostium with one pair of thin and extensive scaled sclerotized stripes on dorsum, bending laterally downwards and backwards; left paramere longer than wide and straight, without distal tooth.

Female genitalia ( Fig. 4c View FIGURE 4 ). Gonocoxite 1 subtriangular; gonocoxite 2 largely sickle shaped, apex slightly acuminate; outer margin slightly curved, dorsal surface concave, almost all covered with numerous setae, inner margin with 7–8 setae; ventral surface convex, smooth.

Intraspecific variation. There is some variability in the number of umbilicate elytral pores (24 to 29). There is also some variation in the number of subapical pores (male:1; female: 2) and in the location of the 4 apical extra pores in the lengthening of the imaginary 6 th striae (male) or 7 th (female), 6 th striae (male) or 7 th interval (female), 5 th intervals (male) or 6 th (female) and 3 rd intervals (male) or 4 th (female).

Etymology. This species is named in honour of Peter Scḩle (Herrenberg, Germany), a well-known specialist on tiger and ground beetles of Africa who has strongly collaborated with us and kindly provided all the specimens of this new species.

Remarks. The new species is more akin to Macrocheilus scapularis (Reiche, 1843) and M. allardi Basilewsky, 1957 than to the other African species by the elytral colour pattern (cf. Fig. 1d View FIGURE 1 vs Figs. 11a View FIGURE 11 and 1e View FIGURE 1 ). Macrocheilus schuelei n. sp. can be separated from the former species by the more transverse pronotum, the posterior angles of pronotum slightly obtuse and rounded at apex (acute and slightly rounded in M. scapularis ), the legs totally brown (tibiae blackish in M. scapularis ) and different shape of labrum (cf. Figs. 2d View FIGURE 2 and 12a View FIGURE 12 ) and of median lobe of aedeagus (cf. Figs. 3c View FIGURE 3 and 13b View FIGURE 13 ). The new species differs from M. allardi by the shorter body, the head, pronotum, scutellum, mouthparts and legs colour (cf. Figs. 1d and 1e View FIGURE 1 ), a lesser securiform shape of the last palpomere of maxillary palps, more transverse and different shape of pronotum and of labrum. Macrocheilus schuelei n. sp. differs from the other African species of this genus by the elytral colour pattern and the median lobe shape, among other external morphological characters.