Psammoecus Latreille, 1829

Karner, Michael, 2014, Three new species and new records of African Psammoecus Latreille (Coleoptera, Silvanidae), European Journal of Taxonomy 89, pp. 1-18 : 16-17

Key to the African species of Psammoecus Latreille, 1829

Psammoecus laetulus Grouvelle, 1914 appears in couplets 12 and 15 of the determination key by intent, reflecting the high morphological variability that is observed in this species.

1 Lateral margins of pronotum without teeth; only anterior and posterior groups of small teeth present ………………………………………………………………………………………………………2

– Lateral margins of pronotum with various number of large or small teeth …………………………3

2 3 rd antennomere shorter than 2 nd; elytral rows of punctures narrower than interstices ………………… …………………………………………………………………………… lateralis (Grouvelle, 1899)

– 3 rd antennomere longer than 2 nd; elytral rows of punctures somewhat wider than interstices ………… ………………………………………………………………………… longicornis Schaufuss, 1872

3 Body length 3.40 – 4.20 mm; lateral margins of pronotum with very small teeth; 1 st antennomere more than 3x as long as 2 nd …………………………………………………………………………………4

– Body length not more than 3.30 mm; lateral margins of pronotum with distinct teeth, 1 st antennomere less than 3x as long as 2 nd ………………………………………………………………………………5

4 Antennomeres 3 – 10 wide, stout ( Fig. 5A ); median lobe of aedeagus wide, abruptly narrowed towards apex ( Fig. 5B ) ……………………………………………………………… grandis Grouvelle, 1908

– Antennomeres 3 – 10 slender ( Fig. 4D ); median lobe of aedeagus slender, gradually narrowed towards apex ( Fig. 4G ) ……………………………………………………………………… procerus sp. nov.

5 Interstices of lateral striae of elytra with large denticles; pronotum with very long lateral teeth ……………………………………………………………………………… spinosus Grouvelle, 1882

– Interstices of lateral striae of elytra with very small denticles or small tubercles ……………………6

6 Anterior angle of pronotum without denticle ( Fig. 6B ) ………………………… sinuaticollis sp. nov. – Anterior angle of pronotum with distinct denticle ……………………………………………………7

7 1 st antennomere less than 2x as long as 2 nd ……………………………………………………………8 – 1 st antennomere not less than 2x as long as 2 nd ………………………………………………………10

8 3 nd antennomere longer than 2 nd ……………………………………… marginicollis Grouvelle, 1908 – 3 rd antennomere as long as 2 nd …………………………………………………………………………9

9 Striae on elytral disk narrower than interstices; lateral teeth of pronotum with narrow bases …………………………………………………………………………… personatus Grouvelle, 1919

– Striae on elytral disk wider than interstices, lateral teeth of pronotum with wide bases …………………………………………………………………………………… leleupi Karner, 2012

10 Maximum pronotal width near middle (excluding lateral teeth) …………………………………11 – Maximum pronotal width in anterior third (excluding lateral teeth) ………………………………15 11 Lateral teeth of pronotum slender, with narrow bases ……………………………………………12 – Lateral teeth of pronotum triangular, with wide bases ……………………………………………13

12 Reticulate microsculpture on disk of pronotum ……………………… hacquardi Grouvelle, 1889 – Microsculpture on disk of pronotum absent ……………………………… laetulus Grouvelle, 1914

13 Elytral striae distinctly wider than interstices; humeral swelling, a transverse band in the middle of elytra, elytral suture along posterior two thirds and elytral apex dark; parameres short, stout, fused with basal piece …………………………………………………… simoni Grouvelle, 1892

– Elytrae with round macula and darkened suture near apex; parameres abruptly narrowed towards apex ………………………………………………………………………………………………14

14 Elytral striae slightly wider than interstices; median lobe of aedeagus slender, evenly narrowed towards apex ( Fig. 3A ) ………………………………………………………… luchti Karner, 2012

– Elytral striae narrower than interstices, median lobe of aedeagus wide, abruptly narrowed towards apex ( Fig. 2E ) ……………………………………………………………… nyakabuyensis sp. nov.

15 Elytrae with dark humeral area, wide dark band across middle and dark suture near apex; or only with darkened band behind middle, sometimes interrupted near suture; parameres gradually narrowed towards apex ……………………………………………………………… laetulus Grouvelle, 1914

– Elytral striae narrower or only slightly wider than interstices; parameres distinctly separated from basal piece ………………………………………………………………………………………16

16 Lateral margin of pronotum with 4 distinct teeth between small posterior tooth and anterior group of small teeth ……………………………………………………… trimaculatus Motschulsky, 1858

– Lateral margin of pronotum with 5 distinct teeth between small posterior tooth and anterior group of small teeth …………………………………………………………… parallelus Grouvelle, 1919

Figures

Fig. 5. Psammoecus grandis Grouvelle, 1908. A. Right antenna. B. Median lobe. C. Parameres. Scale lines = 0.5 mm.

Fig. 4. Psammoecus procerus sp. nov., holotype. A. Habitus. B. Head. C. Pronotum. D. Right antenna. E–G. Aedeagus (E = ventral, F = lateral, G = dorsal view). Scale lines: A = 1.0 mm, B–G = 0.5 mm.

Fig. 6. Psammoecus sinuaticollis sp. nov., holotype. A. Habitus. B. Head and pronotum. C. Right antenna. D–F. Aedeagus (D = ventral, E = lateral, F = dorsal view). Scale lines: A = 1.0 mm, B–C = 0.5 mm, D–F = 0.2 mm.

Fig. 3. Psammoecus luchti Karner, 2012. A. Median lobe. B. Parameres. Scale lines = 0.2 mm.

Fig. 2. Psammoecus nyakabuyensis sp. nov., holotype. A. Habitus. B. Head. C. Pronotum. D. Right antenna. E. Aedeagus, ventral view. F. Paramere, lateral view. G. Median lobe, lateral view. Scale lines: A = 1.0 mm, B–D = 0.5 mm, E–G = 0.2 mm.