Helochares (Hydrobaticus) normatus ( LeConte, 1861 )

Short, Andrew Edward Z. & Girón, Jennifer C., 2018, Review of the Helochares (Hydrobaticus) MacLeay of the New World (Coleoptera: Hydrophilidae: Acidocerinae), Zootaxa 4407 (1), pp. 29-50 : 42-45

Helochares (Hydrobaticus) normatus ( LeConte, 1861)

Figs. 3 B–D, 5B–C, 6A, 8, 9B, 10A.

Philhydrus normatus LeConte 1861: 341 .

Helochares normatus ( LeConte, 1861) . Horn 1890: 252.

Chasmogenus normatus ( LeConte, 1861) . Zaitzev 1908: 383.

Helochares (Hydrobaticus) normatus ( LeConte, 1861) . Knisch 1924: 194.

? Helochares seriatus Sharp, 1882: 76 . Syn.: d’Orchymont 1943: 4.

? Helochares regularis Sharp, 1882: 76 . Syn.: d’Orchymont 1943: 4.

Type material examined. Holotype (sex unknown): “ Bodega [California]”, “ P. normatus / Lec.”, “ Type /3102 [red paper]” (MCZ).

Other material examined (492). COSTA RICA: Guanacaste Province: Highway 1, 0.2 km S of Santa Rosa National Park, in rocky pool E of Highway , 10 52.62'N, 85 35.28'W, 15.vi.2003, leg. A.E.Z. Short (46: SEMC, INBio) ; Rio Santa Rosa at Highway 142, 5 km NE of Las Canas, creekside pools, 17.vi.2003, leg. A.E.Z. Short (23: SEMC, INBio) ; Rio Seco at Highway 1, N of Cirvelas, pools along river, 17.vi.2003, leg. A.E.Z. Short (1: INBio) ; near Carmona, Finca Agua Fria, margin of Rio Carmona , 15.i.2003, leg. A. Short, R. Roughley & W. Porras (1: SEMC) ; Rio Animas at Hwy 4, 210 m, detrital pools and backwaters, 13.i.2004, leg. A.E.Z. Short & D. Lebbin, AS-04-040 (2: SEMC, INBio) ; same locality but 14.vi.2003 (3: INBio) ; Finca Jenny , 30 km N Liberia, 240 m, ii.1994, leg. E. Araya (3: INBio) ; Barra Honda National Park , 3 km NE Nacaome, 100 m, iii.1993, leg. M. Reyes (1: INBio) ; Guanacaste National Park, Playa Naranjo [Naranjo Beach], iv.1991, leg. E. Alcazar (1: INBio) . EL SALVADOR: 15 mi. SW La Union, 31.vii.1965, leg. P.J. Spangler (6, USNM) ; 7 mi. SE Cd. Arce , 3.viii.1965, leg. P.J. Spangler (17, USNM) . HONDURAS: 10 mi. W. Choluteca, 29.vii.1965, leg. P.J. Spangler (5, USNM) ; San Marcus Colon , 28.vii.1965, leg. P.J. Spangler (29, USNM) . MEXICO: Baja California: Sierra Juarez, Canon de Guadalupe , 16.v.1986, G. Challet (4, SEMC) ; Arroyo de Calamajue, near Calamajue , 9.iv.1961, leg. A.G. Smith (6, CAS) ; Arroyo de la Purisima , 1 mi. upstream from town, 28.xii.1958, leg. H.B. Leech (5, CAS) ; Arroyo Saltito, nr. Las Cruces , E of La Paz, 23.i.1959, leg. H.B. Leech (2, CAS) ; Canon San Bernardino , Boca de la Sierra, 3 mi. NW of Miraflores, 19.i.1959, leg. H.B. Leech (8, CAS) ; La Suerte, Sierra San Pedro Martin , 4.vi.1963, leg. R.K. Benjamin (4, CAS) ; Arroyo Santo Domingo , 5.7 mi. E. Hamilton Ranch, dam site, 23.iv.1963, leg. Leech & Arnaud (9, CAS) . Baja California del Sur : 7 mi. W. Santiago, Arroyo San Jorge, 900 ft., 17.vii.2004, leg. W. Shepard (9, SEMC) . Colima: 29 mi. NE of Colima , 3.xii.1948, leg. H.B. Leech (2, CAS) . Morelos: Cuernavaca , 14 mi. S., 8.xii.1948, leg. H.B. Leech, mineralized sulphur stream (1, CAS) . Nayarit: 19 mi. SE of Tepic , 27.xi.1948, leg. H.B. Leech (5, CAS) ; 20 mi SE of Tepic , pool in drying stream bed, 23.ix.1948, leg. H.B. Leech (3, CAS) ; 25 mi SE of Tepic , 23.xi.1948, leg. H.B. Leech (7, CAS) . Puebla: Lago Alchichica , 18.xii.1948, leg. H.B. Leech (1, CAS) . Sonora: Hermosillo , 9-16.vii.1953, leg. B. Malkin (14, CAS) . Veracruz: 1 mi SE of Puente Jula , 18.xii.1948, leg. H.B. Leech (1, CAS) ; Rio Metlac , nr. El Fortin, 17.xii.1948, leg. H.B. Leech (2, CAS) . NICARAGUA: Madriz: Somoto , 28.vii.1965, leg. P.J. Spangler (27, UNSM) ; Rivas: 22 mi. S. Rivas, 26.vii.1965, leg. P.J. Spangler (3, USNM) ; Managua: 13 mi N. Sn Benito, 11.vii.1965, leg. P.J. Spangler (19, USNM) . Matagalpa: km 77.6, PanAm Hwy , 1290’ elev., roadside pool, 4.viii.2002, leg. W.D. Shepard (1, SEMC) . UNITED STATES: Arizona: Cochise Co., Benson , 25.iii.1933 (3, CAS) ; Pima Co., Organ Pipe Cactus National Monument , 27.x.1961, leg. E.L. Sleeper (1, CAS) ; Pima Co., Tucson, various dates (3, CAS) ; Gila Co., Pine ( Natural Bridge ), 28.vii.1956, leg. W.E. Steiner (1, USNM) ; Santa Cruz Co., 11.5 mi SE of Arivaca , 25.ix.1968, leg. P.S. Bartholomew (1, CAS) ; Cochise Co., Rt. 80, 5.3 mi S. Apache, 5.viii.2003, pool by trestle, leg. A.E.Z. Short, AS-03-041 (2, SEMC) ; Santa Cruz Co., Nr. Rt. 39, Sycamore Canyon , 6.viii.2003, pools in creekbed, leg. A.E.Z. Short, AS-03-052 (13, SEMC) . Santa Cruz Co., Rt. 39 at Entrance to Pena Blanca , 7.viii.2003, stock tank, leg. A.E.Z. Short, AS-03-055 (1, SEMC) . California: Alameda Co., Berkeley, leg. F.E. Winters (1, CAS) ; Butte Co., Richardson Springs , 10.v.1955 (5, CAS) ; Eldorado Co., Rubicon River at Georgetown-Ralston Road , 28.vii.1963, leg. H.B. Leech (1, CAS) ; Fresno Co., Waltham Creek , various dates, leg. H.B. Leech (12, CAS) ; Inyo Co., Grinshaw Take, Tecopa , 22.iii.1967, leg. H.B. Leech (1, CAS) ; Inyo Co., Saline Valley , 2.iv.1960, freshwater spring, leg. J. Sedlacek (24, CAS) , Kern Co., 5 mi. NW of Walker Pass , 1.iv.1960 (1, CAS) ; Oak Creek, Oak Creek Pass Road at Cameron Canyon Road, S. of Monolith , 20.iii.1960, leg. H.B. Leech (1, CAS) ; Lake Co., Bartlett Creek, Bartlett Springs , 1.viii.1955, leg. H.B. Leech (2, CAS) ; Lake Co., Lucerne , 28.v.1949, leg. H.B. Leech (1, CAS) , Los Angeles Co., San Gabriel Mts, Big Rock Creek , 31.iii.1959, leg. P.H. Raven (2, CAS) ; Los Angeles Co., Evey Canyon , 4.iv.1955, leg. R.K. Benjamin (1, CAS) ; Mariposa Co., Piney Creek at Hwy 132, 19.viii.1962, leg. H.B. Leech (6, CAS) ; Monterey Co., Arroyo Seco , 31.v.1958, leg. D.D. Linsdale (1, CAS) ; Napa Co., Chiles Creek, 1.7 mi N. of Highway 128, 23.viii.1964, leg. H.B. Leech (1, CAS) ; Riverside Co., Riverside , leg. F.E. Winters (1, CAS) ; San Bernardino Co., Klinefelter, 1.5 mi N. on Route 66 on Route 95, leg. 28.iii.1972, leg. H.B. Leech (1, CAS) ; San Bernardino Co., Mojave River near Victorville , 12.ii.1956, leg. R.K. Benjamin (55, CAS) ; San Diego Co., 12 mi. N. Escondido, 17.iv.1953, leg. R.K. Benjamin (1, CAS) ; San Diego Co., Mountain Palm Springs, Anza Desert , 14.iv.1965 (4, CAS) ; San Luis Obispo Co., Cholame Creek , 1 mi S. Cholame, 1.v.1963, leg. Leech & Arnaud, (2, CAS) ; Santa Barbara Co., Cuyume river , 10 mi. E. Santa Maria, 21.vii.1952, leg. H.B. Leech (6, CAS) ; Santa Barbara Co., Santa Inez Mts , leg. F.E. Winters (2, CAS) ; Stanislaus Co., Del Puerto Creek , 4 mi. by road W. of Freeway Rt. No. 5, 3.ix.1971, leg. H.B. Leech (2, CAS) ; Tuolumne Co., Jackass Creek , 4.2 mi. SE of Priest on Coulterville Rd, 19.viii.1962, leg. H.B. Leech (1, CAS) ; Tulare Co., Deer Creek , leg. H.B. Leech (1, CAS) ; Colusa Co., Lodoga-Stonyford Rd. , W of Ladoga, 1200’ elev., 5.viii.2001, leg. A.E.Z. Short (37, SEMC) ; Colusa Co., Rt. 20 at Bear Creek , 10.viii.2003, leg. A.E.Z. Short, creek margin, AS-03-060 (5, SEMC) ; San Bernardino Co., Zzyzx Springs , off I–15, 8.viii.2003, leg. A.E.Z. Short, AS-03-057 (1, SEMC) ; Ventura Co., Los Padres National Forest, Matilija Creek , leg. A.E.Z. Short, AS-06-077 (11, SEMC) ; Santa Barbara Co., Los Padres National Forest, Oso Canyon , Oso Creek , leg. A.E.Z. Short, 8.viii.2004, AS-04-0125 (2, SEMC) ; Imperial Co., Hot Spring, Frink , 4.viii.1969, leg. Gunstream & Chew (1, SEMC) ; Imperial Co., Wister , 29.viii.1969, leg. Gunstream & Chew (1, SEMC) ; Imperial Co., Calipatria , 9.vi.1922, leg. W. Benedict (3, SEMC) . Nevada: Clark Co., Moapa (1, USNM) ; Clark Co., Warm Springs, Pelocoris Meadow , 26-27.xii.1948, leg. LaRivers & B.H. Banta (1, CAS) ; Nye Co., Amargosa Hot Springs , 31.iii.1953 (1, CAS) ; Nye Co., Clay Camp, Ash Meadows , 25.iii.1964 (2, CAS) . Oregon: Josephine Co., Lake Selmac , 6.ix.2016, leg. A.E.Z. Short , US 16-0906-05B (4, SEMC) . Texas: Brewster Co., Hwy 170, 1.7 mi E. Lajitas, 2.viii.2003, creek pools, leg. A.E.Z. Short, AS-03-029 (1, SEMC) ; Kerr Co., Kerryville, Guadalupe River , 27.viii.1962, leg. H.R. Burke (3, CAS) ; Jeff Davis Co., Ft. Davis , 19.vi.1953 (1, CAS) ; Travis Co., Austin , 7.iv.1924 (2, CAS) ; Val Verde Co., Del Rio , 5.xi.1949, leg. O. Bryant (1, CAS) ; “S. Geronimo ”, 15.vii.1942, leg. E.S. Ross (2, CAS) ; Blanco Co., Cypress Mill (2, USNM) ; McLennan Co., 12 mi. S. of Waco , 18.x.1956, leg. J.R. Zimmerman (2, USNM) ; Crockett Co., 30 mi. W. Ozona, at Live Oak Creek , 18.iii.1976, leg. W.E. Steiner (5, USNM) ; Uvalde Co., Uvalde (at Neuces River ), 28.vi.1976, leg. W.E. Steiner (1, USNM) .

Differential diagnosis. Body size 4.2–6.0 mm. Elytra with ten rows of serial punctures, which are typically not impressed into grooves across most of its range. Clypeus pale yellow to light brown in color, not strongly darkened medially ( Fig. 5 B–C). Abdominal ventrites typically very dark brown, though some specimens in Mexico have been observed with a lighter brown abdomen (it is never orange or yellow as in some H. nexus ); pubescence sparse, such that glabrous areas between setae are visible ( Fig. 6A ) and long, such that the length of the setae are longer than the longest setae on the metaventrite. Aedeagus ( Fig. 8 ) 2.0 to 2.7-times longer than its greatest width; apex of parameres oblique ( Figs 8C, 8E ) to truncate ( Figs 8A, 8B, 8D ), with outer corners widely rounded; inner corners of apex of parameres forming an acute angle; lateral outer margins of parameres usually parallel, only slightly diverging on apical third; median lobe with apex broadly rounded, usually with median acute projection.

Most specimens of this species (particularly those in the US) can be separated from all other New World Hydrobaticus by the sparsely pubescent abdominal ventrites (densely pubescent in H. maculicollis and H. nexus ). Perhaps the most reliable character with which this species can be diagnosed is its aedeagal form, specifically the nearly parallel sided parameres and the mesally projected apex of the median lobe.

Distribution. This species is known as far north as Oregon and as far south as Costa Rica. Within the US, it is strictly a western/southwestern species, and has been recorded as far east as Texas ( Fig. 10A ).

Biology. This species has been found in a variety of habitats, including gravel stream bars in rivers ( Fig. 9B ), the muddy margins of ponds and lakes, and the remnant pools in an otherwise dry riverbed. It generally seems to be associated with lentic habitats or slow-moving streams and rivers. It is sometimes encountered in very large numbers. This species has been observed to carry its egg case.

Remarks. The high morphological variation within H. normatus combined with the high genetic divergence and structuring within the species leads us to conclude that it is likely a species complex. The specimens from the northwestern portion of its range (e.g. the “true” H. normatus ) are supported as genetically distinct from those in the more southern part of its range (Arizona to Costa Rica). Specimens from the southern portion of the range also tend to be smaller on average. Others (such as those in central Mexico, but not further south in Costa Rica) have slightly paler abdominal ventrites. More study and more sampling is needed to further clarify the status of this lineage.

Figures

FIGURE 3. Dorsal habitus images of Helochares (Hydrobaticus) spp. (A) H. maculicollis (Pennsylvania), (B) H. normatus (California), (C) H. normatus (California, lighter form), (D) H. normatus (Arizona).

FIGURE 5. Heads of Helochares (Hydrobaticus) spp. (A) H. maculicollis (Pennsylvania), (B) H. normatus (California), (C) H. normatus (Arizona), (D) H. nexus n. sp., (E) H. zamora n. sp., (F) H. trujillo n. sp., (G) H. championi, (H) H. sp. A., (I) H. politus n. sp.

FIGURE 6. Abdomens of Helochares (Hydrobaticus) spp. (A) H. normatus, (B) H. maculicollis, (C) H. nexus n. sp. (Panama, ventrites paler on lateral thirds), (D) H. nexus n. sp. (Panama, uniformly pale ventrites).

FIGURE 8. Aedeagi of Helochares (Hydrobaticus) normatus. (A) Oregon, (B) California, (C) Arizona, (D) Mexico, (E) Costa Rica.

FIGURE 9. Habitat of Helochares (Hydrobaticus) spp. (A) Habitat of H. trujillo n. sp. in Venezuela [collecting event VZ09- 0121-04X], (B) Habitat of H. normatus in California, (C) Habitat of H. nexus n. sp. in Venezuela [collecting event VZ09-0129- 01A], (D) Habitat of H. maculicollis in Kansas (USA).

FIGURE 10. Distribution of New World Helochares (Hydrobaticus) spp.