Afromicracis Schedl, 1959

Jordal, Bjarte, 2021, Small, uniform, and rarely collected-an integrated taxonomic revision of Afromicracis bark beetles (Coleoptera, Scolytinae), Zootaxa 4981 (1), pp. 70-88 : 72-73

Afromicracis Schedl, 1959

= Miocryphalus Schedl, 1939 , synonym by Alonso-Zarazaga and Lyal (2009), name unavailable

Type species: Afromicracis kenyaensis Schedl, 1959 (original designation).

Diagnosis. Antennal scapus in both sexes straight, as long as or slightly longer than funiculus, slightly dilated at apex, as broad as pedicel; females in some species with a fine tuft of scant long setae, otherwise with few short setae; funiculus (including pedicel) 5-segmented; club on anterior face usually with one procurved suture close to apex, smooth and suture-free on posterior face. Elytra with scale-like or hair-like setae, a single row on each interstriae; strial setae minute or absent. Procoxae contiguous. Protibiae twisted, with 2 or 3, (rarely 4 or 5) lateral and apical denticles. Metatibiae with three lateral and apical denticles. Ventral setae simple, unifid. Proventriculus with a cluster of 3–10 strong crop spines attached to a tubercular base in front of the apical plate; apical teeth transverse or lightly curved, finely dentate; masticatory teeth smooth, closing teeth free, not compact. Male genitalia with a long flagellum, sometimes straight and broad, sometimes very long and coiled; tegmen difficult to assess, either reduced or absent, apophyses more than twice as long as aedeagal body; spiculum gastrale about as long as or slightly shorter than aedeagus ( Figs 56–57 ).

Remarks. Gender feminine as outlined by Alonso Zarazaga and Lyal (2009). In the key to species, be aware that morphological differences can be subtle and specimens which are badly preserved or otherwise slightly deviant from type material should be tried in alternative directions in the key and compared to photos ( Figs 2–53 ). Also note that sexual dimorphism varies from no dimorphism at all, to moderate differences in the apical width of the scapus and the density and length of setae on its dorsal side, and in the presence of impressed frons. Only a single holotype or very few specimens from the type series are available for study in some species, possibly only of one sex; additional variation could therefore appear in new samples.

Key to the species of Afromicracis

1 Frons with densely placed coarse setae; antennal club much longer than broad; pronotum gently rounded, asperities as tiny granules; strial setae short, mainly erect; apicolateral margin of meso- and metatibiae with two anteriorly curve denticles............................................................................. see Laximicracis Jordal (2021a)

- Frons with few, fine setae; antennal club not much longer than broad; pronotum strongly declivous on anterior half, summit distinctly hunchbacked; strial setae on elytra largely recumbent; apical and lateral margin of metatibia usually with three straight spines ( Afromicracis ).................................................................................. 2

2 Protibia with 3–5 lateral teeth; male frons concave, dorsal edge strongly carinate ( Figs 25, 27 )........................ 3

- Protibiae with 2 or 3 lateral and apical teeth; male frons flat or convex........................................... 4

3 Epistoma smooth, male frons impunctate, glabrous, upper and lateral margin with blunt interrupted ridges................................................................................................... A. concava sp. nov.

- Epistoma with two small tubercles, male frons with upper corners of impressed area acutely pointed, concave area finely punctate with scattered seta ( A. elongatula may possibly run here, type lost).................................... A. longa

4 Anterior margin of male pronotum with four projecting teeth; interstrial setae short and bristle-like, scant, appearing nearly glabrous............................................................................ A. depilata , sp. nov.

- Anterior margin of male (and female) pronotum with at most two tiny granules, elytra with rows of closely placed erect interstrial setae.......................................................................................... 5

5 Interstrial setae hair-like, or sometimes bristle-like, never spatulate ( Figs 2–4 )..................................... 6

- Interstrial setae always broad and spatulate, sometimes truncated at tips.......................................... 8

6 Slender species,> 2.6 × as long as wide; interstrial setae very fine, hair-like.............................. A. robusta

- Stouter species, <2.4 × as long as wide; interstrial setae hair- and bristle-like..................................... 7

7 Plump species, elytra and venter combined <1.4 × longer than high; elytral declivity long and steep, longer than elytral disc, transition from disc abrupt and slightly hunchbacked; declivital interstria with fine granules............ A. crassa sp. nov.

- Normal body proportions, elytra and venter> 1.6 × longer than high; elytral declivity gradually rounded, shorter than disc; interstriae smooth...................................................................... A. crinita sp. nov.

8 Setae on antennal scapus in females very dense, the tuft of setae very broad, longer than scapus; body 2.6–2.7 × as long as wide..................................................................................... A. kenyaensis

- Antennal scapus with scattered short setae, females in some species with distinct small tuft of setae, but always shorter than scapus; most species <2.6 × as long as wide............................................................... 9

9 Interstrial setae separated by their length or more; female scapus with small tuft of setae ( Figs 44–46 )................. 10

- Interstrial setae separated by less than their length; female scapus with scant setae................................ 11

10 Female frons with fine, scattered setae, particularly on upper half; pronotal asperities (in both sexes) subcontiguous.................................................................................................. A. congona

- Female (and male) frons nearly glabrous (except epistoma); asperities, particularly on anterior one-third of pronotum, separated by their size........................................................................ A. brevipilosa sp. nov.

11 Frons with pair of broadly spaced longitudinal carinae near antennal insertion........................... A. natalensis

- Frons without longitudinal carinae...................................................................... 12

12 Recumbent strial setae at least as long as distance between them ( Figs 28, 29 ).................................... 13

- Recumbent strial setae much shorter than distance between them, sometimes barely visible......................... 14

13 Pronotal asperities small, spaced by their size or more; ventral setae as short as interstrial setae; body 2.5–2.6 × as long as wide............................................................................. A. ghanaensis , sp. nov.

- Pronotal asperities very broad, subcontiguous; ventral setae much longer than interstrial setae; body 2.2–2.3 × as long as wide................................................................................. A. densisetosa , sp. nov.

14 Setae on posterior half of pronotum coarse, almost spatulate; frons (sex?) weakly concave; protibiae with one lateral and three apical teeth................................................................................. A. jasminiae

- Setae on posterior half of pronotum hair-like ( Figs 13, 14 ); frons variably flattened; protibiae with one lateral and two apical teeth.............................................................................................. 15

15 Frons with sharp granules on upper half, epistoma densely setose; interstrial setae spatulate, separated by at least their length, in straight rows.............................................................................. A. setifera

- Frons smooth, epistoma glabrous on median third; interstrial setae bristle-like, separated by less than their length, setae on declivity slightly confused..................................................................... A. mikaniae

Figures

FIGURES 55–57. Internal body structures in Afromicracis. Proventriculus (55) and male aedeagus (56) of A. densisetosa and male aedeagus of A. concava (57).

FIGURES 2–11. Dorsal lateral and front view of Afromicracis robusta paratype, from the holotype locality (2, 5, 8), Afromicracis crinita holotype (3, 6, 9), and Afromicracis crassa male allotype (4, 7, 10) and female holotype (11).

FIGURES 12–20. Dorsal lateral and front view of Afromicracis jasminae holotype (12, 15, 18), Afromicracis mikanie female paratype compared to holotype (13, 16, 19), and Afromicracis setifera lectotype (14, 17, 20).

FIGURES 21–27. Dorsal lateral and front view of Afromicracis concava male holotype (21, 23, 25), female allotype (26), and Afromicracis longa holotype (male?) (22, 24, 27).

FIGURES 28–37. Dorsal lateral and front view of Afromicracis ghanaensis holotype (28, 31, 34), Afromicracis densisetosa male allotype (29, 32, 36) and female holotype (35), and Afromicracis kenyaensis holotype (30, 33, 37).

FIGURES 38–46. Dorsal lateral and front view of Afromicracis brevipilosa female holotype (38, 41, 44), Afromicracis congona female paratype (39, 42, 45), and A. congona female specimen from Cameroon (40, 43, 46).

FIGURES 47–53. Dorsal lateral and front view of Afromicracis depilata male holotype (47, 49, 51) and female allotype (52), and Afromicracis natalensis holotype (48, 50, 53).