New Mixaderus species from the Mascarene Islands (Coleoptera: Aderidae) Author Gompel, Nicolas text Zootaxa 2021 2021-05-10 4969 1 166 174 journal article 6449 10.11646/zootaxa.4969.1.9 7df98a98-71ab-478e-a1ad-4e193fdff912 1175-5326 4746053 1718FD2A-8B8B-4864-9256-438A992DE4BE Updated key to Mixaderus species from the Mascarene Islands For illustration of the characters referred to in this key, see previous synopsis in Gompel (2012) . 1. Elytra uniformly coloured, legs entirely pale................................................................ 2 - Elytra bicolour: brown or black, with a pattern of pale stripes and spots.......................................... 6 2. Head, thorax and abdomen entirely black.................................................................. 3 - Head, thorax and abdomen entirely pale................................................................... 4 3. Elytra mat, species from Madagascar .............................................................. M. perrieri - Elytra shiny, species from La Réunion .............................................................. M. voisini 4. Thorax transverse............................................................................... M. snelli - Thorax as long as wide......................................................................... M. simplex 6. Antennae thick, densely pubescent and entirely dark......................................................... 7 - Antennae thinner, yellow to partially dark.................................................................. 9 7. Antennomeres 4‒10 transverse........................................................................... 8 - Antennomeres 4‒10 as long or longer than wide. Length < 2mm ................................. M. angustefasciatus 8. Pattern of white pubescence extending to the posterior fifth of the elytra. Length> 2mm ................ M. ptinomorphus - Pattern of white pubescence excluded from the posterior third of the elytra. Length < 2mm ............... M. reunionensis 9. Elytra brown with an alternating pattern of whitish and dark bands................................... M. mauritiensis - Elytra with a different coloration........................................................................ 10 10. Elytra dark with a single transverse yellow stripe, located in their anterior half.................................... 11 - Elytra pigmentation more complex, involving at least two pale, transverse and sinuate stripes, or multiple patches........ 12 11. Elytral stripe broad, reaching the humeral region laterally........................................... M. basithorax - Elytral stripe narrower, remote from the humeral region........................................ M. cinereofasciatus 12. Anterior elytral stripe strongly sinuate.................................................................... 13 - Anterior elytral stripe broad, with weak or no sinuation, sometimes reduced to discrete blotches, or pattern more complex. 16 13. Thorax transverse.................................................................................... 14 - Thorax as long as wide...................................................................... M. poussereaui 14. Anterior elytral stripe extends anteriorly and posteriorly along suture.................................. M. mantillerii - Anterior stripe not extended along suture................................................................. 15 15. Posterior stripe with a deep, loop-shaped sinuation............................................. M. sinuatefasciatus - Posterior stripe with milder sinuation............................................................. M. emmerezi 16. Apex of elytra with a broad, distinct band of pale pigmentation (whitish or yellow)................................ 17 - Apex of elytra dark, at most with a very narrow stripe of pale pigmentation, but then pronotum pale, contrasting with the overall darker elytra........................................................................................ 18 17. Elytra with three simple transversal yellow stripes. Base of pronotum only marked with withe pubescence.... M. madecassus - Elytra with a complex pattern of white pubescence, not limited to simple stripes. Pronotum entirely covered with whitish pubescence................................................................................... M. tamisieri 18. Pronotum pale, contrasting sharply with the dark head and elytra....................................... M. chassaini - Background color of the pronotum similar to the background color of the head and elytra, with at most a pattern of pale pubescence.............................................................................................. 19 19. Yellow humeral spot barely visible. Elytra less than 3.5 longer than pronotum.................................... 20 - Yellow humeral spot distinct. Elytra 3.5 totimes longer than pronotum.................................. M. superbus 19. Antennae at least partially dark, male foretarsae with first tarsomere slightly wider than next ones............... M. gomyi - Antennae entirely yellow, male foretarsae with first tarsomere twice as wide as the following............... M. lemagneni