Mixaderus mauritiensis, Gompel, 2021

Gompel, Nicolas, 2021, New Mixaderus species from the Mascarene Islands (Coleoptera: Aderidae), Zootaxa 4969 (1), pp. 166-174 : 173

Mixaderus mauritiensis n. sp.

( Figures 1c , 2m,w )

Etymology. The species’ name refers to its geographical origin.

Type locality. Republic of Mauritius: Curepipe [20°19’ S 57°31’ E] .

Distribution. Republic of Mauritius.

Description. Body length. ♀ holotype: 1.5 mm. Body pale yellow, head light brown, pronotum and elytra with weak markings. Appendages yellowish-orange with darker femora.

Head. Transverse, light brown, distinctly wider than pronotum. Frons weakly convex. Palpi yellowish-orange. Punctuation extremely fine, dense, punctures small. Pubescence double, dense, wholly, whitish, homogeneous, largely covering the tegument. Eyes well separated from the posterior edge of the head in side view ( Figure 2v ).

Antennae ( Figure 2m ). Short, thin, entirely yellowish, pubescent, with antennomeres 7‒11 forming a weak club. Antennomeres 8‒10 strongly transverse, antennomere 11 thick, more than twice longer than penultimate.

Pronotum. Small, distinctly transverse, side straight and converging posteriorly, trapezoidal. Disc weakly convex, with a broad patch of slightly darker pigmentation. A pair of very shallow dimples just anterior to the posterior border. Surface mat, densely punctuated, punctures deep and relatively big, the space between punctures equivalent to the puncture diameters. Pubescence double, whitish, not masking the tegument.

Elytra. Length: ♀ holotype: 1.08 mm. Long, sides subparallel, with humeral callus well marked. Punctuation strong and deep, dense, space between punctures smaller than the puncture diameters. Disc convex. Pubescence dense, white, comprised of setae borne from the punctuation and interspersed pruinosity, only partially masking the tegument. A distinct pattern of light brown pigmentation the elytra, comprised of a mark on each side of the scutellum, an uninterrupted transversal band at the onset of the posterior declivity, and an apical darkening.

Legs. Simple, tarsae of all legs yellowish, foretibiae yellowish, tibiae of mid- and hindlegs yellowish, with their proximal halves brown, all femora brown in their proximal halves.

Aedeagus. Male unknown.

Type material. Republic of Mauritius: Curepipe , (560 m) [20°19’ S 57°31’ E], 29.III.1939, J. Vinson leg. (1 ♀ paratype, BMNH) .

Figures

FIGURE 1. Habitus of new species of Aderidae from the Mascarene Islands. a, Mixaderus reunionensis n. sp. (♂ holotype from La Réunion); b, Mixaderus tamisieri n. sp. (♂ paratype from La Réunion); c, Mixaderus mauritiensis n. sp. (♀ holotype from Mauritius); d, Mixaderus chassaini n. sp. (♂ holotype from La Réunion); e, Mixaderus lemagneni n. sp. (♂ paratype from La Réunion); f, Mixaderus voisini n. sp. (♀ paratype from La Réunion). Scale bars: 0.5 mm.

FIGURE 2. Anatomy of new species of Aderidae from the Mascarene Islands. a–g: aedeagus of a, Mixaderus reunionensis n. sp. (♂ holotype from La Réunion); b, Mixaderus chassaini n. sp. (♂ holotype from La Réunion); c, Mixaderus tamisieri n. sp. (♂ paratype from La Réunion); d, Mixaderus lemagneni n. sp. (♂ paratype from La Réunion); e, Mixaderus gomyi Gompel, 2012 (♂ holotype from La Réunion); f–g, Mixaderus voisini n. sp.: f, anterior struts retracted (♂ holotype from La Réunion); g, anterior struts extended from phallobase (♂ paratype from La Réunion). h–o: antennae of h, Mixaderus reunionensis n. sp. (♂ holotype from La Réunion); i, Mixaderus chassaini n. sp. (♂ holotype from La Réunion); j, Mixaderus tamisieri n. sp. (♂ paratype from La Réunion); k, Mixaderus lemagneni n. sp. (♂ paratype from La Réunion); l, Mixaderus gomyi Gompel, 2012 (♂ holotype from La Réunion); m, Mixaderus mauritiensis n. sp. (♀ holotype from Mauritius); n, Mixaderus voisini n. sp. (♀ paratype from La Réunion). o,p: male right prothoracic tarsae of o, Mixaderus gomyi Gompel, 2012 (♂ holotype from La Réun- ion); p, Mixaderus lemagneni n. sp. (♂ paratype from La Réunion). q–v: Mixaderus head schematics in side view. q, Mixaderus reunionensis n. sp.; r, Mixaderus chassaini n. sp.; s, Mixaderus tamisieri n. sp.; t, Mixaderus lemagneni n. sp.; u, Mixaderus voisini n. sp.; v, Mixaderus mauritiensis n. sp. Scale bars: 0.1 mm.