Ochthebius (Aulacochthebius) continentalis, Orchymont, 1929

Perkins, Philip D., 2023, Taxonomic revision of African water beetles in the genus Ochthebius Leach (1815) subgenus Aulacochthebius Kuwert (1887) (Coleoptera: Hydraenidae), Zootaxa 5228 (5), pp. 501-546 : 518-519

O. (Aulacochthebius) continentalis Orchymont

Figs. 1 , 4 , 5 , 9 , 24 , 27

O. (Aulacochthebius) continentalis Orchymont 1929: 196

Type locality: “ Afrique Orientale Anglaise ” [i.e., Kenya]

Material examined (175): Angola: Pediva, ca. 30 mi. E. of Porto Alexandre, (16°17′4.2′′S, 12°33′46.8′′E), 26- 27.iv.1954, leg. J. Balfour-Browne (302) (22 NHMUK) ; same locality, 27.iv.1954, leg. J. Balfour-Browne (303) (2 NHMUK) ; Tampa , elev. 1219 m (15°30′S, 13°27′E), 15.vi.1954, leg. J. Balfour-Browne (274) (8 NHMUK) ; Vana e Lombe, near Tampa, (15°30′S, 13°30′E), 14.vi.1954, leg. J. Balfour-Browne (269) (3 NHMUK) ; Giraul, 5 mi. N. Mocamedes, sea level, in small sandy pools above beach, Stn. No. 282, (15°11′52.08′′S, 12°9′27.36′′E), 20.vi.1954, leg. J. Balfour-Browne (282) (12 NHMUK) . Kenya: Kilifi Co., Kaloleni , 1.7km W of along road C107, KEN 16-33, 3.8148S 39.6149E, 181m, 29.I.2016, Large pond with sedge at edges as part of stream, 29.i.2016, leg. J. Bergsten & O. Bistrom (1 male KNM) ; Kaloleni , road C107, KEN 16-32, 3.8155S 39.6229E, 174m, 29.i.2016, leg. J. Bergsten & O. Bistrom (1 male, 2 females KNM) ; Taita _Taveta Co., Gimba village, W side of Sagalla, Taita Hills , KEN 16-35, 3.4421S 38.55.77E, 653m, 30.I.2016, Partly dry streambed with pools and hygropetric sites over bedrock, 30.i.2016, leg. J. Bergsten & O. Bistrom (1 female KNM) . Namibia: Kaokoveld, Kunene River , Swartbooisdrift , (17°19′S, 13°49′E), 10.ii.1975, leg. Endrödy-Younga (#645) (3 TMSA) . South Africa: Eastern Cape Province, Transkei: Qora River , (32°16′S, 28°47′E), 2.iii.1985, leg. Endrödy-Younga (#2179) (2 TMSA) ; KwaZulu-Natal Province, Hluhluwe Game Res. , (28°5′S, 32°4′E), 19.xi.1992, leg. Endrödy-Younga (#2832) (10 TMSA) ; same locality, 27.xi.1992, leg. Endrödy-Younga (#2861) (3 TMSA) ; same locality, 27.xi.1992, leg. Endrödy-Younga (#2862) (9 TMSA) ; Hluhluwe Game Reserve , (28°5′S, 32°4′E), 17.xi.1992, leg. Endrödy-Younga #2824 (#2824) (23 TMSA) ; Mtubatuba , (28°22′S, 32°19′E), 4.iv.1974, leg. Endrödy-Younga (#318) (4 TMSA) ; Ndumu Game Reserve , (26°53′S, 32°16′E), 12.vi.1989, leg. Endrödy-Younga & Klimaszewski (#2612) (2 TMSA) ; Limpopo Province, N. Transvaal, Waterberg, Farm 223, Mogol River , (24°11′S, 27°50′E), 13.ii.1976, leg. A. Strydom, Endrödy-Younga (#1039) (17 TMSA) ; Mpumalanga Province, Bundu Inn , (25°28′S, 28°55′E), 24.iii.1974, leg. Endrödy-Younga (#304) (8 TMSA) ; c. Transvaal, Roodeplaat Dam , (25°37′S, 28°23′E), 14.viii.1974, leg. Endrödy-Younga (#359) (20 TMSA) ; Kruger Nat. Pk., Letaba River below dam, (23°46′S, 31°30′E), 1.iii.1995, leg. Endrödy-Younga (#3122) (4 TMSA) ; Nelshoogte galery forest below St., (25°51′S, 30°53′E), 2.xii.1986, leg. Endrödy-Younga (#2343) (1 TMSA) .

Differential diagnosis. Differentiated from other members of the O. (A.) continentalis Group by the combination of the metaventral tabella surface on each side with slightly oblique longitudinal shallow groove with setigerous punctures, and by the aedeagus.

Redescription. Size: specimen from South Africa (length/width, mm): body (length to elytral apices) 1.30/0.62; head width 0.38; pronotum length 0.30, width at base 0.27, width at hyaline border 0.54; elytra 0.78/0.62. Habitus as illustrated ( Fig. 9 ). Dorsum dark brown to black except hyaline borders of prothorax transparent. Eyes with moderately coarse, convex facets. Frons with deep impressions, borders of impressions rounded. Frons and clypeus densely punctate, rugulose, densely setose. Labrum anterior margin arcuate in both sexes.

Pronotum densely setose, moderately coarsely punctate except finely punctate on disc; anterior and posterior transverse impressions deep, anterior narrowly separated from shallow transverse impression immediately behind anterior margin of lateral lobe; median longitudinal impression deep, connecting anterior and posterior transverse impressions. Pronotum lateral hyaline borders wide, extended from posterior to anterior angles; sides of non-hyaline part with long conspicuous setae immediately above and resting on hyaline border; anterior and posterior hyaline borders narrow.

Elytra wider than non-hyaline part of pronotum, posteriorly rounded, sides arcuate; ten seriate-punctate, punctures large, deep, intervals narrow; each puncture with granule at anterior margin, and conspicuous decumbent seta that arches over puncture; lateral margin with row of short, arcuate setae that extend outward from margin in dry specimens.

Venter ( Fig. 9 ): Mentum with sparse, moderately large setigerous punctures. Prosternum with very low midlongitudinal carina. Metaventrite tabella large, crown shaped, width ca. 0.56 width of metaventrite, slightly wider than long (ratio ca. 48:43), lateral angles slightly rounded, anterior angle prolonged as distinct carina that attains mesoventral intercoxal process; surface on each side with slightly oblique longitudinal shallow groove with setigerous punctures, area between grooves with few random setigerious punctures; setae along posterior margins longer than setae along anterior margins.Abdominal venter: first two ventrites and anterior margin and lateral areas of third with hydrofuge pubescence, remainder of ventrites dull, microreticulate, with sparse setae; setae longer on last ventrite (male).

Remarks. The specimen imaged ( Fig. 9 ) has the following locality data: Kruger Nat. Pk., Letaba River below dam, (23°46′S, 31°30′E), 1.iii.1995, leg. Endrödy-Younga (#3122).

Distribution. Currently known from Angola, Kenya, Namibia, and South Africa ( Figs. 23 , 26 ).

Figures

FIGURE 1. Dorsal habitus of species in the O. (A.) exaratus Group (upper row), and the O. (A.) continentalis Group (remainder).

FIGURE 4. Venter and aedeagi (ventral view, flagellum deleted) of species in O. (A.) continentalis Group and O. (A.) tenuipunctus Group. Not to same scale.

FIGURE 5. Aedeagus of O. (A.) continentalis, showing the folded and gradually unfolding condition of the flagellum.

FIGURE 9. O. (A.) continentalis Orchymont, habitus and aedeagus of specimen from South Africa.

FIGURES 24–26. Geographical distributions. 24. O. (A.) continentalis Orchymont. 25. O. (A.) scutatus n. sp. 26. O. (A.) persetosus n. sp. and O. (A.) flagellissimus n. sp.

FIGURES 27–28. Geographical distributions. 27. O. (A.) species in Kenya and Uganda. 28. O. (A.) strangulatus Régimbart, O. (A.) tenuipunctus Régimbart and O. (A.) nigeriensis n. sp.

FIGURES 22–23. Geographical distributions. 22. O. (A.) copiosus n. sp. 23. O. (A.) latissimus n. sp.