Hydraena cooperi Balfour-Browne

PERKINS, PHILIP D., 2014, A revision of the water beetle genus Hydraena Kugelann for southern Africa (Coleoptera: Hydraenidae), Zootaxa 3758 (1), pp. 1-92 : 7-11

Hydraena cooperi Balfour-Browne

Figs. 2 (habitus), 4 (aedeagus), 65 (map)

Hydraena cooperi Balfour-Browne 1954: 98 .

Type material. Holotype (male): South Africa : Eastern Cape Province, Piggott Bridge Road, 33° 18' S, 26° 32' E, 20 iii 1939, J. Omer-Cooper. Labels: "Type [red disc]// SOUTH AFRICA, Albany District, Piggott Bridge Rd. 20.iii.39// J. Omer Cooper coll.// Hydraena (s. str.) cooperi Type J. Balfour-Browne det." (BMNH).

Material examined (1161): Angola: Rocadas, R. Cunene, 16° 45' S, 14° 59' E, 19-22 ii 1972, Southern African Exp. BM (2 BMNH); Botswana: 5 km NW San-ta-Wani Safari Lodge, 19° 27' S, 23° 38' E, 8-9 iii 1993, J. Deckert (2 ZMHB); same locality, 19° 27' S, 23° 38' E, 8-9 iii 1993, M. Uhlig (2 ZMHB); Chobe NP, Savuti-Camp, lux, 18° 33' S, 24° 3' E, 11 iii 1993, M. Uhlig (2 ZMHB); Namibia: East Caprivi: Katima Mulilo, lux, 17° 29' S, 24° 17' E, 8 iii 1992, M. Uhlig (6 ZMHB); South Africa: Transvaal, Waterburg Dist., Deel Kraal, pools in vlei, 26° 30' S, 27° 19' E, 22 viii 1948, J. Omer-Cooper (11 BMNH); Eastern Cape Province, 11 mi. from Matatiele, Kokstad road, in roadside pond, 30° 10' S, 28° 50' E, 28 iii 1954, J. Balfour-Browne (112) (10 BMNH); 5 mi. NW Grahamstown, 33° 15' S, 26° 28' E, 19 iii 1968, P. J. Spangler (2 USNM); Albany District, Gowie’s Kloof, 33° 18' S, 26° 32' E, 6 viii 1939, J. Omer-Cooper (6 BMNH); Amatole, Pirie Forest Station, shore washing, 32° 43' S, 27° 17' E, 8 xii 1987, Endrödy-Younga (#2563) (1 TMSA); Storms Rivier, in swampy backwater, 33° 59' S, 23° 52' E, 19 iii 1954, J. Balfour-Browne (8 BMNH); Elliot, small muddy, weedy stream, 30° 55' S, 26° 41' E, 27 iii 1954, J. Balfour-Browne (103) (3 BMNH); Farm Dam nr. Mooi River, mud with Juncus and Nitella , elev. 1295 m, 31° 0' S, 28° 30' E, 2 iv 1954, J. Balfour-Browne (134) (1 BMNH); Gatberg River, site 16, MVOC; ECR 47N, 30° 29' S, 27° 24' E, 12 vi 1990 (6 AMG); Grahamstown, 33° 18' S, 26° 32' E, 1-30 v 1939, J. Omer-Cooper (3 BMNH); Grahamstown, Teafontein Farm, 33° 18' S, 26° 32' E, 5 viii 1939, J. Omer-Cooper (15 BMNH); Joubertskraal River, at Joubertskraal Farm, stones in current; SCR 120, 33° 46' S, 24° 10' E, 1 xii 1993, F. C. de Moor & H. M. Barber-James (3 AMG); Kingwilliamstown, Maden dam, boggy pond close to Maden dam, 32° 53' S, 27° 24' E, 25 iii 1954, J. Balfour-Browne (93) (2 BMNH); Kingwilliamstown, Maden dam, edges of Maden dam, deep water, 32° 53' S, 27° 24' E, 25 iii 1954, J. Balfour-Browne (94) (5 BMNH); Maclear District, near Ugle, flooded pasture along deep river, elev. 1340 m, 31° 5' S, 28° 22' E, 27 iii 1954, J. Balfour-Browne (105) (4 BMNH); near Wildebees River, Small muddy pool, fringed with sedges, at side of road, marginal vegetation out of current, ECR 115, 31° 12' S, 28° 5' E, 26 iii 1993, unknown (17 AMG); nr. Humansdorp, Gamtoos River, small shallow pool cut in reeds, 34° 0' S, 24° 48' E, 20 iii 1954, J. Balfour-Browne (10 BMNH); Piggott Bridge Road, 33° 18' S, 26° 32' E, 20 iii 1939, J. Omer-Cooper (23 BMNH); Road between Queenstown and Lady Frere, on stones in running water in small stream, elev. 1158.24 m, 31° 54' S, 27° 40' E, 26 iii 1954, J. Balfour-Browne (97) (1 BMNH); Transkei: Qora River, shore washing, open river, 32° 16' S, 28° 47' E, 2 iii 1985, Endrödy-Younga (#2179) (8 TMSA); Tributary of Modi River, (Maclear Municipal Dam), MVOC; ECR 124G, 31° 3' S, 28° 18' E, 27 iii 1993 (2 AMG); Tsitsikamma Mts., 40 km E Plettenberg Bay, 34° 5' S, 23° 21' E, 7 iii 1997, Hess & Heckes (22) (20 NMW); Uitenhage District, Van Staaden’s Pass, in gravel at edge of fast stream, 33° 54' S, 25° 12' E, 21 iii 1954, J. Balfour- Browne (84) (3 BMNH); Warrenton, groundtraps (unbaited), 28° 8' S, 24° 51' E, 30 i 1979, Endrödy-Younga & F. de Moor (#1542) (1 TMSA); Wilderness NP, car catcher, 33° 59' S, 22° 38' E, 29-30 xi 1996, M. & B. Uhlig (1 ZMHB); Wilderness NP, Langvlei, Malachite bird hide, Juncus krausi and bush litter sievings, 33° 59' S, 22° 41' E, 30 xi 1996, B. & M. Uhlig (49 ZMHB); Free State Province, 15 km NW Klaserie, Guernsey Farm, woodland black lights, elev. 500 m, 24° 5' S, 31° 15' E, 18-30 xii 1985, S. & J. Peck (4 CMNO); 15 km NW Klaserie, Guernsey Farm, woodland evening car netting, elev. 500 m, 24° 5' S, 31° 15' E, 19-31 xii 1985, S. & J. Peck (9 CMNO); 30 km E Nylstroom, flight intercept trap, 24° 42' S, 28° 23' E, 15 xi–17 xii 1984, H. & A. Howden (1 CMNO); Waterberg District, Plat River, river, 25° 10' S, 28° 5' E, 6-18 iv 1905, C. Swierstrai (1 BMNH); KwaZulu-Natal Province, Bergville, Mont-aux-sources, farm dam, thick weed at edges, elev. 1220 m, 28° 41' S, 29° 10' E, 6 iv 1954, J. Balfour-Browne (147) (2 BMNH); Injambili (or Ntshambili) River, on inland rd. nr. Umzumbe, marginal vegetation; NAT 77R-S, elev. 2 m, 30° 31' S, 30° 37' E, 7 vi 1972, F. M. Chutter (1 AMG); Karkloof Grassveld, floating debries, 29° 19' S, 30° 15' E, 12 ix 1989, Endrödy-Younga & Klimaszewski (#2753) (3 TMSA); Mtubatuba, air plankton, 28° 22' S, 32° 19' E, 4 iv 1974, Endrödy-Younga (#324) (13 TMSA, 31 TMSA); Mtubatuba, air plankton (dark), 28° 22' S, 32° 19' E, 4 iv 1974, Endrödy-Younga (#325) (3 TMSA); Mtubatuba, sandy shore washing, 28° 22' S, 32° 19' E, 4 iv 1974, Endrödy-Younga (#318) (1 TMSA); Ndumu Game Reserve, shore washing, fresh water, 26° 53' S, 32° 16' E, 12 vi 1989, Endrödy-Younga & Klimaszewski (#2612) (91 TMSA); Ndumu Game Reserve, shore washing, salty water, 26° 54' S, 32° 16' E, 12 vi 1989, Endrödy- Younga & Klimaszewski (#2613) (108 TMSA); Ngwagwane River nr. Riverside, above confluence with Umzimkulu, marginal vegetation; NAT 30AB-AD, elev. 3 m, 29° 44' S, 30° 5' E, 13 vi 1972, H. Metz (2 AMG); Polela River, Himeville, marginal vegetation; NAT 56K-M, elev. 2 m, 29° 44' S, 29° 31' E, 13 vi 1972, F. M. Chutter (2 AMG); St. Lucia, Gwalagwala Tr., coastal forest with many lianas; FMHD #2004-044, flight intercept trap, elev. 10 m, 28° 23' S, 32° 24' E, 7-20 ii 2004, Newton, Solodovnikov, Thayer (1088) (1 FMNH); Umhlungwa River on old S. coast rd., nr. Hibberdene, marginal vegetation; NAT 82N-P, elev. 3 m, 30° 34' S, 30° 32' E, 7 vi 1972, F. M. Chutter (1 AMG); Umzimkulu River at The Rocks, marg. veg., NAT 67T-V, 29° 49' S, 29° 31' E, 15 vii 1972, unknown (5 AMG); Weza, Impetyene Forest, forest, +/- 17 km from Station, shore washing, 30° 38' S, 29° 39' E, 26 xi 1989, Endrödy-Younga & Klimaszewski (#2719) (7 TMSA); Weza, Impetyene Forest, lower forest, shore washing, large and rapid forest river with stony banks, 30° 37' S, 29° 42' E, 19 ii 1989, Endrödy-Younga (#2697) (1 TMSA); Zululand, Dukuduku For. Sta., air plankton, sunset, 28° 22' S, 32° 19' E, 4 iv 1974, Endrödy- Younga (#323) (181 TMSA, 22 TMSA); Limpopo Province, Naboomsp. Torino Ranch, 24° 37' S, 28° 38' E, 14 i 1990, Endrödy-Younga (2774) (16 TMSA, 70 TMSA); Naboomsp. Torino Ranch, UV light, woody sav., 24° 37' S, 28° 38' E, 14 i 1990, Endrödy-Younga (2773) (4 TMSA); Nylsvley, at river, in river, 24° 40' S, 28° 42' E, 24 v 1976, W. Breytenbach (11 TMSA); Nylsvley Nature Reserve, light trap, 24° 39' S, 28° 42' E, 1-30 iv 1980, E. Grei (4 SANC); Mpumalanga Province, Roodeplaat, UV light trap, 25° 34' S, 28° 22' E, 17-18 iii 1960, Neubecker (3 TMSA); Waterval farm, at light, 25° 35' S, 28° 16' E, 12 xii 1991, R. Dixon (2 TMSA); Western Cape Province, Concordia, near Knysna, Scirpus fringed vlei, 29° 32' S, 17° 57' E, 17 iii 1954, J. Balfour-Browne (10 BMNH); Du Toits Mts., 8 km SE Franschhoek, 33° 55' S, 19° 8' E, 28 ii 1997, Hess & Heckes (1 NMW); Elandsdrift, shore washing, 34° 39' S, 19° 53' E, 24 ii 1981, Endrödy-Younga (#1747) (6 TMSA); Franschhoek, rd. R45, river 3 km NW Franschhoek, 33° 52' S, 19° 2' E, 25 iii 2001, I. Ribera & A. Cieslak (19) (2 MNCN); Groot R., nr. Plettenberg Bale, in brackish water ditches, 34° 3' S, 23° 22' E, 18 iii 1954, J. Balfour-Browne (2 BMNH); Harkerville Forest, shore washing, 34° 4' S, 23° 10' E, 7 xii 1976, Endrödy-Younga (#1299) (1 TMSA); Knysna District, Knysna- Avontuur Road, farm dam, elev. 275 m, 34° 3' S, 23° 3' E, 17 iii 1954, J. Balfour-Browne (65) (5 BMNH); Knysna Main Forest, small roadside pool, elev. 525 m, 34° 3' S, 23° 3' E, 17 iii 1954, J. Balfour-Browne (101) (20 BMNH); Krom River Stn 4, Stellenbosch; ERS 18B 335629S 185056E, emergent vegetation, 33° 56' S, 18° 50' E, (1 AMG); Little Karroo, Raubenheimer Dam, shore washing, 33° 25' S, 22° 19' E, 21 x 1993, Endrödy-Younga (#2888) (1 TMSA); Little Karroo, Raubenheimer Dam, shore washing, after debris removed, 33° 25' S, 22° 19' E, 21 x 1993, Endrödy-Younga (#2889) (4 TMSA); Nuweberg, 10 km NE, water plankton, 34° 34' S, 19° 15' E, 13 xi 1973, Endrödy-Younga (#239) (24 TMSA); Paarl, shallow weedy rivulet, elev. 130 m, 33° 45' S, 18° 58' E, 10 viii 1954, J. Balfour-Browne (353) (10 BMNH); near Wellington, muddy shallow pool, grit bottom with Typha , elev. 92 m, 33° 37' S, 18° 59' E, 10 viii 1954, J. Balfour-Browne (354) (10 BMNH); River Homdini, Goukamma Bridge, edge of river, among thick weed, 34° 1' S, 22° 48' E, 15 iii 1954, J. Balfour-Browne (10 BMNH); Paarl, Small, shallow, muddy ephemeral pool, elev. 130 m, 33° 45' S, 18° 58' E, 10 viii 1954, J. Balfour-Browne (352) (3 BMNH); Plettenberg Bay, 34° 5' S, 23° 25' E, 14 iii 1968, P. J. Spangler (3 USNM); Reed fen along road to Keurboomsrivier, 7 km NE of Plettenberg Bay, 34° 0' S, 23° 22' E, 19 ix 2009, D. T. Bilton (7 DTBC); S. W. Cape, Betty’s Bay, on coast line between Gordon’s Bay and Hermanus, Vlei (lower), in Typha , (FRW 117 L-N), 34° 20' S, 19° 1' E, 2 i 1956 (1 AMG); S. W. Cape, Nuweberg, 10 km NE, shore washing, 34° 34' S, 19° 6' E, 13 xi 1973, Endrödy- Younga (#240) (15 TMSA, 90 TMSA); SW Cape, Verlorevlei Farm, shore washing, 32° 19' S, 18° 22' E, 28 viii 1981, Endrödy-Younga (#1857) (4 TMSA); Temp. pool beside R324 road 12 km S. of Barrydale, below Tradouw Pass, 33° 59' S, 20° 42' E, 19 ix 2009, D. T. Bilton (2 DTBC); W. Cape, Hawequas, shore washing, 33° 34' S, 19° 8' E, 10 xi 1973, Endrödy-Younga (#226) (1 TMSA); Wildcliff Nature Preserve, “Bridge Pool”, 33° 58' S, 21° 2' E, 1 vii–30 viii 2008, Z. Gidó (6 AMG); Wildcliff Nature Preserve, “Far Meadow” swamp, 33° 58' S, 21° 2' E, 1 vii–30 viii 2008, Z. Gidó (3 AMG); Wildcliff Nature Preserve, “Misty Meadow” swamp, 33° 58' S, 21° 2' E, 1 vii–30 viii 2008, Z. Gidó (11 AMG); Wilderness NP, stream in road to Swartvlei, 33° 59' S, 22° 37' E, 22 iii 2001, I. Ribera & A. Cieslak (8) (31 MNCN); Wilderness NP, Swartvlei/Montmere, ditch by the lake, 33° 59' S, 22° 37' E, 22 iii 2001, Ribera & A. Cieslak (1 Ribera); Witte Els Bosch, Groot River, rapid stream, weeds & moss, dead edges, 34° 0' S, 24° 6' E, 19 iii 1954, J. Balfour-Browne (78) (1 BMNH); Zimbabwe: Matopos [Matabo] National Park, 20° 33' S, 28° 30' E, 1-2 iv 1968, P. J. Spangler (4 USNM); Salisbury (Highlands), grass along marsh, 17° 50' S, 31° 5' E, 4 xi 1960, I. M. Newell (5027) (2 MCZ); Victoria Falls National Park, blacklight, 17° 58' S, 25° 50' E, 3-6 iv 1968, P. J. Spangler (8 USNM); Victoria Falls: Zambezi-NP-Camp, lux, 17° 53' S, 25° 49' E, 11-12 xii 1993, M. Uhlig (2 ZMHB).

Differential diagnosis. Very similar in dorsal habitus and ventral characters to H. cooperoides ( Figs. 2 , 3 ). Reliable determinations will require careful examination of the aedeagi ( Figs. 4, 5 ). See also the diagnosis of H. humanica .

Description. Size: Holotype (length/width, mm): body (length to elytral apices) 1.45/0.64; head 0.24/0.38; pronotum 0.37/0.48, PA 0.40, PB 0.46; elytra 0.89/0.64. Dorsum of head piceous; pronotum light brown around piceous macula; elytra brown; legs light brown to testaceous; maxillary palpi testaceous.

Frons punctures ca. 1xef, larger and denser near eyes than medially; interstices shining, 0.5–1xpd laterally, 1– 4xpd medially. Clypeus mcr laterally, very finely sparsely punctulate medially. Mentum weakly concave medially, moderately densely finely punctulate, interstices shining; postmentum punctate, with deep depression on each side. Genae raised, shining, without posterior ridge.

Pronotum laterally slightly emarginate in front of and behind middle; anterior margin straight behind eyes, emarginate behind frons, scintilla absent; punctures on disc slightly larger than those of frons, interstices strongly shining, 1–4xpd, punctures slightly larger and denser at anterior and posterior; PF1 absent; PF2 very shallow; PF3 shallow; PF4 very shallow or obsolete.

Elytra weakly arcuate laterally; summit of posterior declivity slightly behind midlength; lateral explanate margin narrow; on basal 1/3 punctures ca. 2xpd largest pronotal punctures, punctures becoming finer and more widely spaced toward posterior. Intervals not raised, shining, on basal 1/3 ca. 1xpd, as are interstices between punctures of a row. Apices in dorsal aspect weakly separately rounded, in posterior aspect margins forming deep angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 2/1/1/5. P1 laminate; median carina sinuate in profile. P2 l/ w ca. 2/1, sides becoming parallel toward blunt apex, apex raised slightly above mesoventral intercoxal process. Plaques very small, indistinct, oval, margins not strongly demarcated, located at sides of deep median depression. Metaventrite without midlongitudinal carina between intercoxal process and median depression. AIS width at slightly arcuate posterior margin ca. 2x P2. All tibiae slender. Protibiae slightly arcuate, meso- and metatibiae straight. Abdominal apex symmetrical; last tergite with apicomedian notch. Female (microslide mount, n=1): last tergite moderately sharply rounded, with minute apicomedian elevation, ca. 40 hooked setae, very closely set, in irregular row; gonocoxite not midlongitudinally divided, apical margin moderately sharply rounded, low transverse ridge evident at border of microreticulation; spermatheca simple, type C shape.

Distribution. Widely distributed in southern Africa ( Fig. 65 ).

Notes. As noted by Balfour-Browne (1954) in the original description, this species is related to members of the H. erythraea Regimbart species complex. This is a very difficult group, the species of which must be differentiated on the basis of the very tiny aedeagi. The aedeagus is only moderately complicated, but the distal piece is bent at an angle to the main piece, making detailed examination difficult. For much of the range of H. cooperi the aedeagus has a large expansion on the ventral face of the main piece, and this can be used for species identification. However, the lobe is sometimes quite small. Some aedeagal variants are illustrated herein ( Fig. 4 ).

Figures

FIGURE 2. Hydraena cooperi, holotype, dorsal and lateral habitus.

FIGURE 3. Hydraena cooperoides, holotype, dorsal and lateral habitus.

FIGURES 4–5. Aedeagi of holotypes of H. cooperi and H. cooperoides, and aedeagal variants of H. cooperi.

FIGURES 64–65. 64. All known collecting localities for southern African Hydraena. 65. Geographical distributions of Hydraena species.