Rhytomus

Key to adult mainland New Guinea Rhytomus species

Access to online key: https://keys.lucidcentral.org/keys/v4/rhytomus/ (click on the magic wand icon to select the best character to use first)

1 Interstriae 3–5 on basal fifth all having unaligned scattered punctures ( Fig. 11A View FIGURE 11 ); basal pseudepipleural pit present, shallow and slightly larger than stria 10 ( Fig. 11D View FIGURE 11 ).................................................................... 2

- Interstriae 3–5 with at least one interval having two distinct rows of punctures on basal fifth (11B); basal pseudepipleural pit deep and distinctly larger than stria 10 ( Fig. 11C View FIGURE 11 ) OR pseudepipleural pit is absent................................. 5

2 Elytral interval 1 with basal punctures much smaller in size to those in intervals 2–3; pronotal lateral edge obsolete or sharply defined............................................................................................. 3

- Elytral interval 1 with basal punctures similar in size and coarseness to those in intervals 2–3; pronotal lateral edge always sharply defined...................................................................................... 4

3 Pronotal lateral edge obsolete; male clypeal edge without emargination lateral to clypeal teeth ( Fig. 4B View FIGURE 4 ); Body length 4–5.3 mm .................................................................... Rhytomus papuanus ( Paulian, 1985)

- Pronotal lateral edge sharply defined; male clypeal edge with emargination lateral to clypeal teeth ( Fig. 4A View FIGURE 4 ); Body length 3.6–4.1 mm .............................................................. Rhytomus howdeni ( Paulian, 1985)

4 Basal pseudepipleural surface with irregularly distributed more or less defined punctures ( Fig. 11E View FIGURE 11 ); female pygidium depressed apically...................................................... Rhytomus fervidus Saxton & Génier , new species

- Basal pseudepipleural surface with sharply defined ocellate punctures ( Fig. 11F View FIGURE 11 ); female pygidium evenly convex.................................................................................. Rhytomus heurni ( Paulian, 1937)

5 Base of pronotum lacking fine longitudinal depression medially; basal pseudepipleural pit deep and distinctly larger than stria 10 ( Fig. 11C View FIGURE 11 ); male pygidial groove not distinctly narrowed medially ( Figs. 8D, H, I View FIGURE 8 )............................... 6

- Base of pronotum with fine longitudinal depression medially (Fig. E); basal pseudepipleural pit absent; male pygidial groove distinctly narrowed medially and terminating in pits ( Fig. 8E View FIGURE 8 )........ Rhytomus latidentatus Saxton & Génier , new species

6 Interstriae 3, 4 and 5 having two distinct rows of punctures; elytral pubescence long and conspicuous ( Fig. 11B View FIGURE 11 )......... 7

- Interstriae 3 and 5 having unaligned and scattered punctures, interstriae 4 having two distinct rows of punctures; elytral pubescence short and fine (as in Fig. 11A View FIGURE 11 )................................................................. 9

7 Male metatibial apicointernal tooth approximately in line with posterior tibial edge ( Fig. 12C View FIGURE 12 ); pygidium of female depressed basally; body length 3.0– 4.6 mm .................................. Rhytomus sodalis Saxton & Génier , new species

- Male metatibial apicointernal tooth set anteriorly to posterior tibial edge ( Fig. 12D View FIGURE 12 ); pygidium of female evenly convex: body length 4.1–6.0 mm.................................................................................... 8

8 Elytral surface between punctures dull, with distinct microsculptures ( Fig. 7D View FIGURE 7 , 11B View FIGURE 11 ); Body length 4.1–5.4 mm ......................................................................... Rhytomus larseni Saxton & Génier , new species

- Elytral surface between punctures appearing glossy, at most with ill-defined microsculptures ( Fig. 6A View FIGURE 6 ); Body length 6mm ................................................................... Rhytomus elongatus ( van Lansberge, 1885)

9 Elytral surface appearing glossy, at most with ill-defined microsculpture (as in Fig. 12B View FIGURE 12 ); Elytra strongly convex in lateral view ( Fig. 12E View FIGURE 12 ).............................................................. Rhytomus setulosus ( Balthasar, 1965)

- Elytral surface dull, with distinct microsculpture ( Fig. 12A View FIGURE 12 ); Elytra moderately convex in lateral view ( Fig. 12F View FIGURE 12 )........................................................................ Rhytomus vanus Saxton & Génier , new species