Hydrochus beeneni Makhan 1992: 100 Hydrochus piroei Makhan 1992 Taxonomy of Central American water beetles in the genus Hydrochus Leach, 1817 (Coleoptera: Hydrochidae) Perkins, Philip D. Zootaxa 2021 2021-05-21 4974 3 459 503 3N65Y Makhan Makhan 2021 [151,502,1086,1113] Insecta Hydrochidae Hydrochus Animalia Coleoptera 12 471 Arthropoda species beeneni stat. nov.   Figs. 2, 21, 22, 24, 40      Hydrochus beeneni Makhan 1992: 100   Hydrochus piroei Makhan 1992; Oliva (1996)misidentification (see remarks) Originally described from the Cayman Islands. This is a very commonly collected Central American species; all eight countries are represented in the specimen locality data records given below.   Differential diagnosis.Among Central American species, recognized by the combination of moderate size (ca. 2.76 mm), the densely punctate pronotum, the large and deep anteromedian pronotal fovea, the closely spaced serial elytral punctures, and the male genitalia ( Figs. 10–12; described below). This very common species has a generalized  Hydrochushabitus; reliable determinations will require dissection of males. Refer also to the differential diagnosis of  H. biexcavatus  n. sp.   Redescription. Habitus as illustrated ( Figs. 21, 22). Size: Ca. (length/width, mm): body (length to elytral apices) 2.76/1.04; head width 0.64; pronotum l/w 0.62/0.64; PA 0.64; PB 0.56; elytra 1.76/1.04. Body size moderate (ca. 2.76 mm). Dorsum grey to greenish bronze, with strong to moderately strong iridescence, especially in anteromedian fovea of pronotum, elytra with large black spots. Punctation on elytra ca. 2–3x that of pronotum. Elytra interstriae ca. 1–1.5× strial puncture diameter. Interstria 9 thmore convex than others, overhanging 10 thinterstria. Usual area of callus on 5 thweakly raised, moderately elongate, ca. 7 punctures in row on each side. Pronotum slightly wider than long, widest slightly behind anterior margin, narrowed at base, sides arcuate, smooth; anterior margin slightly bisinuate; rather uniformly densely punctate, except less dense in anteromedian fovea; depressions moderately deep, anteromedian deepest. Elytra with spaces between strial punctures narrow walls to ca. 0.5x their diameter; apices rather sharply conjointly rounded in dorsal view, in lateral view outer margin with slight angulation. Ventral characters: Mentum densely punctate, with median fovea. Submentum with two foveae. Legs testaceous, femora darker than tibiae. Male genitalia ( Figs. 21, 22, 24) general characters: paramere tips slender and pointed, much narrower in lateral view than in dorsal/ventral views, in dorsal/ventral views with medial margins at apex parallel or nearly so, then arcuate away from midline; aedeagus slender in dorsal and ventral views; in lateral view slightly wider; lateral margins of aedeagus sclerotized; basal piece shorter than parameres, orifice strongly sclerotized. Dorsal surface: pdmm proximal to paramere tips parallel or nearly so, overlapping margin of aedeagus; adbl large; adtl near distal end; each paramere with sclerotized ridge as illustrated ( Figs. 10, 11). Ventral surface: pvmm more widely separated than pdmm, approximating lateral margin of aedeagus.   Material examined (258):   Belize: Stann Creek, Kendal; ex side pool of Sittee Riverat bridge,  1.v.1987, leg. Spangler& Faitoute(7 NMNH);  Stann Creek, Sittee Point; Possum Point Biol. Sta.,  23.iv.1987, leg. P. J. Spangler& R. A. Faitoute(25 NMNH); same locality,  24.iv.1987, leg. P. J. Spangler& R. A. Faitoute(10 NMNH); same locality,  25.iv.1987, leg. P. J. Spangler& R. A. Faitoute(2 NMNH);  Stann Creek, Sittee Point; Sittee River,  8 kmupstream from Possum Point Biol. Sta.,  22.iv.1987, leg. Spangler& Faitoute(54 NMNH);  Belize Dist., Hattieville,  7-8.vii.1968, leg. W. L. Hasse(1 CNC, 2 NMNH);  Cayo, Western Highway Mile66,  5.vii.1969, leg. W. & D. Hasse(6 NMNH);  Orange Walk Dist., Rio Bravo Pres., black lights,  1.i.1996, leg. W. D. Shepard(3 NMW).   Costa Rica: Port  Limon,  9.v.1929, leg. Darlingon(1 MCZ);  Alajuela, Cano Negro,  24.viii.1998, leg. Drechsel(2 NMW);  Puntarenas, Roadsidepools;  7.9 kmSE of La Palma; Osa Pensla., elev.  34 m( 8°36.07’N, 83°25.95’W),  18.vi.2003, leg. A. E. Z. Short(1 SEMC).   El Salvador: Zacatecoluca,  1.viii.1965, leg. Paul J. Spangler(1 NMNH).   Guatemala: Izabal, Finca Bello Horizonteca  8 kmSE of Rio Dulce, elev.  43 m( 15°35’33.07’’N, 88°56’37.18’’W),  11.iii.2017, leg. R. S. Zack(5 WSU); Peten, Parque National Ixpanpajul, Rt.CA-13, near Santa Ana, elev.  188 m( 16°52.439’N, 89°48.652’),  11.ix.2009, leg. R. S. Zack(3 WSU);  Parque National Yaxha, ENE El Remate, elev.  167 m( 17°4’1.99’’N, 89°24’.72’’W),  13.iii.2017, leg. R. S. Zack(13 WSU).   Honduras: Corozal Town,  29.viii.1967, leg. G. & R. Lacy(2 NMNH);  SanMarcus Colon,  28.vii.1965, leg. Paul J. Spangler(1 NMNH);  Cortes, 24 mi.S. SanPedro Sula,  19.vi.1974, leg. M. E. and P. D. Perkins(1 MCZ);  LaLima,  3.vi.1964, leg. Blanton, Broce, & Woodruff(23 NMNH).   Mexico: Campeche, 21 mi.E.  Campeche,  27.vii.1964, leg. Paul J. Spangler(5 NMNH);  Escarcega,  18.v.1962, leg. F. IslasS. (4 NMNH);  Chiapas, 3 mi. N. Tapilula,  27.v.1974, leg. M. E. & P. D. Perkins(1 SEMC);  Nayarit, SanBlas,  12-14.vii.1960, leg. R. B. Loomis, J. Maris(5 CAS); same locality,  14.vii.1960, leg. R. B. Loomis, J. Maris(1 MCZ);  Oaxaca, Tapanatepec,  23.viii.1965, leg. P. J. Spangler(1 NMNH);  Quintana Roo, Km146 carr Chetumal - Cancun,  3.v.1982, leg. V. Melendez(1 UNAM);  Sonora, Cd. Obregon,  9.viii.1960, leg. W. W. Gibson(2 MCZ);  Tabasco, 23 mi. N. Villahermosa,  6.viii.1964, leg. Paul J. Spangler(34 NMNH);  Frontera,  23.vi.1969, leg. Bright& Campbell(1 NMNH); Mpio. Cdentla Rio Gonzalez Est.4 Lagura Juliva, ( 18°20.757’N, 92°58.213’W),  27.iii.1998, leg. Bueno, Barba(1 UNAM);  Rio Carrizal2nd Secc. Rancheria Platanos( Estanque),  10.vi.1996, leg. J. Bueno, A. Contreres, R. Barba(1 UNAM);  Rio Carrizal Desv. Reforma Km234,  8.vi.1996, leg. J. Bueno, A. Contreres, R. Barba(7 UNAM);  Rio Carrizal Est. No.5, ( 17°58.21’N, 93°8.65’W),  10.vi.1996, leg. J. Bueno, A. Contreres, R. Barba(1 UNAM);  Rio Samaria, Est.4 (estanque), ( 18°.78’N, 93°4.75’W),  13.vi.1996, leg. Bueno, Santiago, Barba, Contreras(1 UNAM);  Teapa,  25.v.1974, leg. M. E. & P. D. Perkins(12 MCZ);  Villahermosa,  25.vii.1964, leg. Paul J. Spangler(1 NMNH);  Veracruz, 25 mi. S. Acayucan,  4.vii.1965, leg. Paul J. Spangler(1 NMNH); 8 Mi.NE Panuco,  28.viii.1965, leg. P. J. Spangler(2 NMNH);  Acayucan,  4.vii.1965, leg. Paul J. Spangler(1 NMNH);  Sn. Jose Las Choapas Est.7 Rio Tonala(vias del tren), ( 17°52.288’N, 94°5.042’),  24.iii.1998, leg. J. Bueno, R. Barba(1 UNAM).   Nicaragua: Carazo, Rio Casares, elev.  110 m( 11°42’57.3’’N, 86°13’6.97’’W),  12.i.2013, leg. M. Brojer(1 NMW);  Matagalpa, Matagalpa, km 77.6 Panam Highway, Rdsidepool, elev.  393 m,  4.viii.2002, leg. W. D. Shepard(2 SEMC);  Rio San Juan,  60 kmSE San Carlos, Refugio Bartola, ex. mercury vapor/UV light, elev.  100 m( 10°58.4’N, 84°20.3’W),  30.v.2002, leg. R. Brooks, Z. Falin, S. Chatzimanolis(5 SEMC);  Rivas, Res Sil Pr Domitila, UVlights, elev.  122 m,  5-9.vi.2005, leg. W. D. Shepard(1 SEMC).   Panama: Bocas del Toro, nr. Miramar, car-net between -82.30/+8.95 -81.19/+9.04,  24.vii.2014, leg. T. Struyve(1 HMNH). Male genitalia ( Figs. 21, 22). General characters: paramere tips slender and pointed, much narrower in lateral view than in dorsal/ventral views, in dorsal/ventral views with medial margins at apex parallel or nearly so, then arcuate away from midline; aedeagus slender in dorsal and ventral views; in lateral view slightly wider, dorsal surface with angulation where adbl and shaft join; lateral margins of aedeagus sclerotized; basal piece shorter than parameres, orifice strongly sclerotized. Dorsal surface: pdmm proximal to paramere tips parallel or nearly so, overlapping margin of aedeagus; adbl large; adtl near distal end; each paramere with sclerotized ridge as illustrated ( Fig. 10). Ventral surface: pvmm more widely separated than pdmm, approximating lateral margin of aedeagus.   Remarks. Oliva (1996)synonymized  H. beeneniMakhanwith  H. piroeiMakhan. Thisproposed synonymy is incorrect. I have examined the holotype, including the holotypemale genitalia of  H. beeneni(RBINS). The male genitalia of the two species distinctly differ; see figure and detailed description of  H. piroeimale genitalia in Perkins (2019c). When the holotypespecimen of  H. beeneniwas received, the male genitalia was in multiple pieces; these pieces are illustrated herein ( Fig. 24), and the dorsal habitus of the holotypeis also illustrated. The male genitalia illustration in Makhan (1992)is oversimplified, only in one view, misleading, and of little diagnostic value. The specimens imaged herein have the following locality data: ( Fig. 21) Veracruz, 25 mi.S. Acayucan, 4.vii.1965, leg. Paul J. Spangler; ( Fig. 22) Bocas del Toro, nr. Miramar, car-net between -82.30/+8.95 -81.19/+9.04, 24.vii.2014, leg. T. Struyve. 3128194590 1987-05-01 NMNH Spangler & Faitoute Belize Sittee River Kendal 13 472 1 Stann Creek 3128194492 1987-04-23 NMNH P. J. Spangler & R. A. Faitoute Belize Possum Point Biol Sittee Point 13 472 1 Stann Creek 3128194328 [509,1366,439,465] 1987-04-24 NMNH P. J. Spangler & R. A. Faitoute Belize Possum Point Biol Sittee Point 13 472 1 Stann Creek 3128194374 1987-04-25 NMNH P. J. Spangler & R. A. Faitoute Belize Possum Point Biol Sittee Point 13 472 1 Stann Creek 3128194376 1987-04-22 NMNH Spangler & Faitoute Belize Sittee River Sittee Point 13 472 1 Stann Creek 3128194516 1968-07-07 1968-07-08 1968-07-07 CNC, NMNH W. L. Hasse Belize Hattieville 13 472 1 Belize 3128194405 1969-07-05 NMNH W. & D. Hasse Belize Western Highway Mile 13 472 1 Cayo 3128194340 [430,1433,583,609] 1996-01-01 NMW W. D. Shepard Belize Rio Bravo Pres. 13 472 1 Orange Walk 3128194485 [151,345,618,645] Port Costa Rica Costa Rica 13 472 1 3128194577 [353,831,619,645] 1929-05-09 MCZ Darlingon Costa Rica Limon 13 472 1 Limon 3128194569 1998-08-24 NMW Drechsel Costa Rica Cano Negro 13 472 1 Alajuela 3128194584 2003-06-18 SEMC A. E. Z. Short Costa Rica 34 8.601167 Osa Pensla. 13 -83.4325 Roadside 13 472 1 Puntarenas 3128194367 [621,1433,690,717] 1965-08-01 NMNH Paul J. Spangler El Salvador Zacatecoluca 13 472 1 3128194361 2017-03-11 WSU R. S. Zack Guatemala 43 15.592519 Finca Bello Horizonte 1 -88.943665 13 472 1 Izabal 3128194536 2009-09-11 WSU Parque National Ixpanpajul, Rt. & R. S. Zack Guatemala 188 16.873983 Santa Ana 13 472 1 Peten 3128194488 2017-03-13 WSU El Remate & R. S. Zack Guatemala 167 17.06722 Parque National Yaxha 13 472 1 3128194463 1967-08-29 NMNH G. & R. Lacy Honduras Corozal Town 13 472 1 3128194307 [512,1260,870,897] 1965-07-28 NMNH Paul J. Spangler Honduras San 13 472 1 3128194354 1974-06-19 MCZ M. E. and P. D. Perkins Honduras San 13 472 1 Cortes 3128194436 1964-06-03 NMNH Blanton & Broce & Woodruff Honduras La 13 472 1 3128194309 [425,766,942,969] Mexico Campeche 13 472 1 Campeche 3128194459 [779,1432,942,969] 1964-07-27 NMNH Paul J. Spangler Mexico Campeche 13 472 1 Campeche 3128194334 [151,697,979,1005] 1962-05-18 NMNH F. Islas Mexico Escarcega 13 472 1 3128194484 1974-05-27 SEMC M. E. & P. D. Perkins Mexico Chiapas 13 472 1 Chiapas 3128194598 [282,1081,1014,1041] 1960-07-12 1960-07-14 1960-07-12 CAS R. B. Loomis & J. Maris Mexico San 13 472 1 Nayarit 3128194483 1960-07-14 1960-07-14 1960-07-12 MCZ R. B. Loomis & J. Maris Mexico San 13 472 1 Nayarit 3128194316 [528,1262,1050,1077] 1965-08-23 NMNH P. J. Spangler Mexico Tapanatepec 13 472 1 Oaxaca 3128194301 1982-05-03 UNAM V. Melendez Mexico Chetumal - Cancun Km 13 472 1 Quintana Roo 3128194554 1960-08-09 MCZ Cd. Obregon & W. W. Gibson Mexico Sonora 13 472 1 Sonora 3128194371 [429,1323,1123,1149] 1964-08-06 NMNH N. Villahermosa & Paul J. Spangler Mexico Tabasco 13 472 1 Tabasco 3128194432 1969-06-23 NMNH Bright & Campbell Mexico Frontera 13 472 1 3128194454 1998-03-27 UNAM Bueno & Barba Mexico 18.34595 Lagura Juliva 1 -92.970215 Rio Gonzalez Est. 13 472 1 3128194455 1996-06-10 UNAM J. Bueno & A. Contreres & R. Barba Mexico Rio Carrizal Estanque Secc. Rancheria Platanos 13 472 1 3128194531 1996-06-08 UNAM J. Bueno & A. Contreres & R. Barba Mexico Rio Carrizal Desv. Reforma Km 13 472 1 3128194507 1996-06-10 UNAM J. Bueno & A. Contreres & R. Barba Mexico 17.970167 Rio Carrizal Est. No. 13 -93.144165 13 472 1 3128194394 1996-06-13 UNAM Bueno & Santiago & Barba & Contreras Mexico Est. -93.07917 Rio Samaria 13 472 1 3128194580 [737,1362,1338,1365] 1974-05-25 MCZ M. E. & P. D. Perkins Mexico Teapa 13 472 1 3128194313 1964-07-25 NMNH Paul J. Spangler Mexico Villahermosa 13 472 1 3128194409 1965-07-04 NMNH S. Acayucan & Paul J. Spangler Mexico Veracruz 13 472 1 Veracruz de Ignacio de la Llave 3128194341 [344,1046,1410,1437] 1965-08-28 NMNH P. J. Spangler Mexico Panuco Mi. 13 472 1 3128194496 1965-07-04 NMNH Paul J. Spangler Mexico Acayucan 13 472 1 3128194539 1998-03-24 UNAM J. Bueno & R. Barba Mexico 17.871468 Rio Tonala 13 472 1 3128194452 2013-01-12 NMW M. Brojer Nicaragua 110 11.715917 Rio Casares 1 -86.218605 13 472 1 Carazo 3128194437 2002-08-04 SEMC W. D. Shepard Nicaragua 393 Rdside Panam Highway 13 472 1 Matagalpa 3128194384 2002-05-30 SEMC R. Brooks & Z. Falin & S. Chatzimanolis Nicaragua 100 10.973333 Refugio Bartola 129 -84.33833 13 472 1 Rio San Juan 3128194471 [151,1204,1626,1653] 2005-06-05 2005-06-09 2005-06-05 SEMC Res Sil Pr Domitila, UV & W. D. Shepard Nicaragua 122 Rivas 13 472 1 Rivas 3128194512 2014-07-24 HMNH T. Struyve Panama Miramar 13 472 1 Bocas del Toro