Aulacochthebius Kuwert 1887
Creators: name: Perkins, Philip D.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Hydraenidae
Aulacochthebius

description: Key to Groups and Species of O. (Aulacochthebius) in Africa and Madagascar
1. Elytral serial rows of punctures distinct, moderately to deeply impressed; metaventral tabella angulate anteriorly and laterally; hydrofuge pubescence of abdominal ventrites various in extent (Fig. 1).......................................... 2
- Dorsal sculpture very fine, very shallowly impressed; elytral serial rows of punctures indistinct, indicated by minute setae, sometimes non-serial, random; metaventral tabella oval; abdominal ventrites 1–4 entirely clothed with hydrofuge pubescence; O. (A.) tenuipunctus Group (Fig. 2)...................................................................... 3
2. Pronotal punctation very fine and sparse, setae very fine and sparse; elytral punctures comparatively shallow, intervals with minute or without granules; first two abdominal ventrites and antero-lateral margin of third with hydrofuge pubescence, remainder of ventrites shining, with very sparse setae; aedeagus with single seta apically on each paramere; O. (A.) exaratus Group (Figs. 1, 3)................................................................................... 10
- Pronotal punctation coarser and denser, setae longer and denser; elytral punctures relatively deep, intervals with distinct granules; abdominal ventrites not as above, more ventrites having hydrofuge pubescence; aedeagal parameres without setae.. O. (A.) continentalis Group (Figs. 1, 4)..................................................................... 12
3. Elytra with serial rows of setae more-or-less uniform; body size larger, ca. 1.40 mm ................................ 4
- Elytra with serial rows of setae less distinct; body size smaller, ca. 1.15–1.25 mm .................................. 6
4. Elytral serial setae very small and widely spaced, each row with wide band of very fine microreticulation, bands separated by extremely weakly raised smooth and shining longitudinal lines (see text and Fig. 20); Madagascar (Figs. 1, 20).......................................................................................... O. (A.) multilineatus n. sp.
- Elytra without such lines............................................................................... 5
5. Pronotum median longitudinal impression very shallow, extending from anterior transverse impression to ca. midlength; aedeagus as illustrated (Figs. 2, 14); Kenya, South Africa .............................. O. (A.) tenuipunctus Régimbart
- Pronotum median longitudinal impression deeper, extending from anterior transverse impression to posterior transverse impression; Madagascar (Fig. 2)..................................................... O. (A.) plicicollis Fairmaire
6. Pronotum and elytra very wide compared to body length...................................................... 7
- Pronotum and elytra width less compared to body length..................................................... 8
7. Elytral serial rows of punctures uniform; Madagascar (Figs. 2, 21)......................... O. (A.) perlaevis (Perkins)
- Elytral serial rows of punctures very irregular; aedeagus as illustrated; South Africa (Figs. 2, 16).... O. (A.) latissimus n. sp.
8. Body size slightly smaller, ca. 1.15 mm; aedeagus as illustrated; Nigeria (Figs. 2, 18)............ O. (A.) nigeriensis n. sp.
- Body size slightly larger, ca. 1.25 mm .................................................................... 9
9. Elytra with serial rows of very shallow, widely spaced punctures, each with very short seta, each row with very narrow band of very fine reticulation; metaventral tabella circular; aedeagus as illustrated; Kenya (Figs. 2, 15).. O. (A.) alienus Orchymont
- Elytra with serial rows of very shallow, widely spaced punctures, each with very short seta, each row without very narrow band of very fine reticulation; metaventral tabella more oval; aedeagus as illustrated; South Africa (Figs. 2, 17). O. (A.) solitarius n. sp.
10. Elytral setae, especially laterally, more numerous and longer, extending outward from body; body size larger, ca. 1.40 mm; elytral punctures more widely spaced; aedeagus as illustrated; southern Africa (Figs. 1, 3, 8)........ O. (A.) copiosus n. sp.
- Elytral setae shorter and less numerous, and, at least posteriorly on elytra not extending outward from body............ 11
11. Aedeagus as illustrated; Africa (Figs. 1, 3, 7)....................................... O. (A.) strangulatus Régimbart
- Aedeagus as illustrated; Palearctic (Figs. 1, 3, 6)......................................... O. (A.) exaratus Mulsant
12. Metaventral tabella surface on each side with slightly oblique longitudinal shallow groove with setigerous punctures (Figs. 2, 4, 5, 9).................................................................... O. (A.) continentalis Orchymont
- Metaventral tabella surface without shallow grooves........................................................ 13
13. Dorsum of head and pronotum microreticulate, setae sparse (Figs. 1, 10)........................ O. (A.) scutatus n. sp.
- Dorsum of head and pronotum non-microreticulate, setae more numerous....................................... 14
14. Abdominal venter with shining large suboval glabrous area bearing sparse, rather long setae, remainder of ventrites with hydrofuge pubescence; South Africa (Figs. 1, 4, 11)...................................... O. (A.) flagellissimus n. sp.
- Abdominal venter hydrofuge pubescence not delimiting an oval non-pubescent area............................... 15
15. Dorsum of head and pronotum with very dense, very prominent setae; abdominal ventrites 1–2 entirely hydrofuge pubescent, ventrite 3 with hydrofuge pubescence absent in ca. median 1/5, ventrite 4 with hydrofuge pubescence absent in ca. median 1/3, ventrite 5 with hydrofuge pubescence present only narrowly laterally, remaining ventrites shining, with sparse setae; aedeagus as illustrated; South Africa (Figs. 1, 4, 12).............................................. O. (A.) persetosus n. sp.
- Dorsum of head and pronotum with very sparse, very fine setae............................................... 16
16. Abdominal ventrites 1–3 entirely bearing rather long hydrofuge pubescence, ventrite 4 with reduced hydrofuge pubescence in median ¼, remaining ventrites shining, with sparse setae; South Africa (Figs. 1, 4, 13)....... O. (A.) mpumalangicus n. sp.
- Abdominal ventrites 1–2 entirely hydrofuge pubescent, ventrite 3 with hydrofuge pubescence only present along anterior margin in ca. median 1/5, “hair-line” then sloping toward posterior margin, lateral 1/3 entirely hydrofuge pubescent; body size large, ca. 1.40 mm; aedeagus as illustrated; Ethiopia, Morocco, Senegal (Figs. 1, 14)............................................................................................. O. (A.) libertarius Aguilera, Ribera & Hernando
description: Published as part of Perkins, Philip D., 2023, Taxonomic revision of African water beetles in the genus Ochthebius Leach (1815) subgenus Aulacochthebius Kuwert (1887) (Coleoptera: Hydraenidae), pp. 501-546 in Zootaxa 5228 (5) on pages 506-507, DOI: 10.11646/zootaxa.5228.5.1, http://zenodo.org/record/7543172