Ochthebius strangulatus Régimbart 1906: 274 O. (Aulacochthebius) exaratus Mulsant Taxonomic revision of African water beetles in the genus Ochthebius Leach (1815) subgenus Aulacochthebius Kuwert (1887) (Coleoptera: Hydraenidae) Perkins, Philip D. Zootaxa 2023 2023-01-17 5228 5 501 546 48FMY Regimbart Regimbart 2023 [151,714,582,609] Insecta Hydraenidae Ochthebius Animalia Coleoptera 15 516 Arthropoda species strangulatus stat. nov. Aulacochthebius   Figs. 1, 3, 7, 27, 28      Ochthebius strangulatus Régimbart 1906: 274   O. (Aulacochthebius) exaratusMulsant; Orchymont 1948. Misidentification.     Typelocality: Kenya( Majiya Chumvi[“ Maji-Chumvi”]; Samburu).  Material examined (51):   Benin: Dep. Mono, Come, Dohi(village), ( 6°23′7.4′′N, 1°56′14.5′′E),  2.ii.2006, leg. Goergen, Komarek& Houngua(7) (1 NMW);  Dep. Mono, Lakossa, Doukonta(village), ca.  40 ma.s.l., ( 6°40′21.3′′N, 1°41′33.5′′E),  2.ii.2006, leg. Goergen, Komarek& Houngua(9) (1 NMW);  Dep. Zou, Zogbodome, Lokoli(forest), Hianzounriv., ( 7°3′N, 2°15′E),  3.ii.2006, leg. Goergen, Komarek& Houngua(14) (2 NMW).   Burkina Faso: Obire, UV light trap,  15.ii.1995, leg. J. F. Cornell(7 NMW).   Gambia: Outside Abuko Nature Reserveat Water Works, 18.30–21.00,  4.xi.1977, leg. Cederholm— Danielsson— Hammarstedt— Hedquist— Samuelsson(1 LUM);  River Tanji,  3 kmSW Brufut, 19.00–21.00,  28.ii.1977, leg. Cederholm— Danielsson— Hammarstedt— Hedquist— Samuelsson(2 LUM).   Ghana: Northern region, Nabogo,  40 kmN of Tamale,  21.i.1970, leg. S. Endrödy-Younga( Nr.410) (6 HNHM);  Nyankpala,  10.ii.1970, leg. S. Endrödy-Younga(3 TMSA).   Kenya: Kilifi Co., Kaloleni, road C107, KEN 16-32, 3.8155S 39.6229E,  174m,  29.I.2016, Poolsin dry streambed, in open landscape,  29.i.2016, leg. J. Bergsten& O. Bistrom(1 KNM);  Killfi Co., Tributaryto Galana river, elev.  6 m( 3°8′15.72′′S, 40°5′53.16′′E),  28.i.2016, leg. J. Bergsten& O. Bistrom(KEN 16-30) (8 KNM).   Mali: Mopti, Niger river, ( 14°30′N, 4°12′W),  21.ii.2000, leg. Komarek& Mayer(21-1) (2 NMW);  San, Bani River, ( 13°18′N, 4°54′W),  22.ii.2000, leg. Komarek& Mayer(22-1) (2 NMW).   Nigeria: Argungu, NW State,  22.xii.1974, leg. J. T. Medler(6 NMNH);  Oyo Provence, Ogbomosho, (12-13)-  II-1949, B. Malkin, ( 8°8′N, 4°15′E) (9 NHMUK).   Senegal:  3 kmSSW Toubakouta, 10 kmS Ziguinchor, 19.00–22.00,  4.iii.1977, leg. Cederholm— Danielsson— Hammarstedt— Hedquist— Samuelsson(2 LUM).   Uganda: Queen Elizabeth National Park, ( 0°8′14′′S, 30°2′28′′E),  2.v.1968, leg. P. J. Spangler(1 NMNH).   Discussion.Orchymont (1929) suggested that  O. (A.) strangulatuswas a junior synonym of  O. (A.) exaratus, under the section on  O. (A.) exaratusin a “Tableau des Espèces” including the phrase [“(?  strangulatusReg.)”]. Later, Orchymont (1948) effectively removed the “?” by expressing the view that there is a transition in dorsal characters from  O. (A.) exaratusto  O. (A.) strangulatus, and cited a male from Nairobi as being “un exemplaire formant passage à  strangulatus.” The catalogue of Hansen (1998)included  strangulatusas one of the synonyms of  O. (A.) exaratus. As is discussed in the  O. (A.) exaratussection on types, the aedeagi of  O. (A.) exaratusand  (A.) strangulatusclearly differ, and represent two species. There are also external differences, mostly pertaining to the distributions and lengths of setae.   Differential Diagnosis.Refer to the differential diagnosis of  O. (A.) copiosus  n. sp.   Redescription. Size: specimen from Kenya(length/width, mm): body (length to elytral apices) 1.12/0.54; head width 0.32; pronotum 0.23/0.40; elytra 0.70/0.54. Habitus as illustrated ( Fig. 7). Dorsum dark brown except hyaline borders of prothorax transparent. Eyes with moderately coarse, convex facets. Frons with deep impressions, borders of impressions rounded, smooth. Clypeus with very few, very shallow finely setigerous punctures. Labrum apicomedially produced in male, rounded in female. Pronotal reliefs very smooth, with very sparse and very short indistinct setae; anterior and posterior transverse impressions deep, anterior narrowly separated from transverse impression immediately behind anterior margin of lateral lobe; median longitudinal impression deep, extended from anterior to posterior impression. Pronotum lateral hyaline borders moderately wide, present only in angulation behind lateral lobes; sides of lateral lobes with short setae that extend outward from cuticle in dry specimens; anterior hyaline border moderately wide; posterior hyaline border narrow. Elytra smooth, ten seriate-punctate, punctures small; on disc each puncture with very fine very short almost imperceptible seta, which lies flat on cuticle, setae more conspicuous and longer laterally and at elytral apices; minute granule at anterior margin of each puncture, more obvious on disc; setae on lateral margins only moderately dense and only moderately long, in dry specimens extending outward from cuticle on in anterior ¼ to 1/3, otherwise mostly lying flat on cuticle. Venter ( Fig. 7): Mentum with sparse, small setigerous punctures. Prosternum with very low midlongitudinal subcarina. Metaventrite tabella large, angulate anteriorly and laterally, length slightly less than width (ratio ca. 7:9); ratio of length above and below horizontal imaginary line through greatest width ca. 3:4; lateral angles slightly rounded; surface with very few, very fine punctures; tabella bordered by moderately long to long setae. Abdominal venter: first two ventrites and antero-lateral margin of third with hydrofuge pubescence, remainder of ventrites shining, with very sparse setae.   Distribution. Currently known from Kenya, Nigeria, and Uganda( Figs. 26, 27). 4979345409 [151,925,788,815] Kenya Maji Maji-Chumvi Chumvi 15 516 1 Samburu holotype 4979345380 2006-02-02 NMW Goergen & Komarek & Houngua Benin 6.385389 Dohi 1 1.9373611 Come 15 516 1 Mono 4979345355 2006-02-02 NMW Goergen & Komarek & Houngua Benin 40 6.672583 Doukonta 1 1.692639 Lakossa 15 516 1 Mono 4979345356 2006-02-03 NMW Goergen & Komarek & Houngua Benin Zogbodome 7.05 Hianzoun 1303 2.25 Lokoli 15 516 1 Zou 4979345317 1995-02-15 NMW J. F. Cornell Burkina Faso Obire 15 516 1 4979345365 1977-11-04 LUM Cederholm & Danielsson & Hammarstedt & Hedquist & Samuelsson Gambia Water Works Outside Abuko Nature Reserve 15 516 1 4979345304 1977-02-28 LUM Cederholm & Danielsson & Hammarstedt & Hedquist & Samuelsson Gambia River Tanji 15 516 1 4979345403 1970-01-21 HNHM S. Endrody-Younga & Nr. Ghana Nabogo 15 516 1 Northern 4979345343 [359,1037,1112,1138] 1970-02-10 TMSA S. Endrody-Younga Ghana Nyankpala 15 516 1 4979345432 2016-01-29 KNM Pools & J. Bergsten & O. Bistrom Kenya 174 -3.8155 Kaloleni 7 39.6229 Co. 15 516 1 Kilifi 4979345314 2016-01-28 KNM J. Bergsten & O. Bistrom Kenya Killfi Co. 6 -3.1377 Galana river 1 40.0981 Tributary 15 516 1 4979345330 2000-02-21 NMW Komarek & Mayer Serbia 14.5 Niger river 1288 -4.2 Mopti 15 516 1 4979345384 2000-02-22 NMW Komarek & Mayer Serbia 13.3 Bani River 1291 -4.9 San 15 516 1 4979345405 [461,1259,1292,1319] 1974-12-22 NMNH NW State & J. T. Medler Nigeria Argungu 15 516 1 4979345301 1949-02 NHMUK Malkin Nigeria 8.133333 Ogbomosho 1302 4.25 Provence 15 516 1 Oyo 4979345332 1977-03-04 LUM Cederholm & Danielsson & Hammarstedt & Hedquist & Samuelsson Senegal 3 km SSW Toubakouta 15 516 1 Ziguinchor 4979345331 [237,1416,1400,1428] 1968-05-02 NMNH P. J. Spangler Uganda -0.13722223 Queen Elizabeth National Park 21 30.041111 15 516 1