New Neotropical and Nearctic species of water beetles in the genera Hydraena Kugelann and Ochthebius Leach, a key to North American genera and subgenera of the family, new distribution records, and a synopsis of ecology, behavior and morphology related to aquatic life (Coleoptera: Hydraenidae) Author Perkins, Philip D. text Zootaxa 2023 2023-11-07 5367 1 1 86 https://www.mapress.com/zt/article/download/zootaxa.5367.1.1/52225 journal article 10.11646/zootaxa.5367.1.1 1175-5334 10145106 5A1E5321-D2BA-4B92-BA23-A7C1CDBA5723 Ochthebius ( s.str. ) tubus Perkins Ochthebius tubus Perkins 1980: 355 The new records below document new localities and new depositories for identified specimens of this species, including the first records from Missouri, North Dakota , and Oklahoma . The species is presently known from western North America between the U.S.A. —Canadian border and central Mexico , and east to Missouri. Most frequently collected in California, where only one of the many records are from the Sierra Nevada Mountains, the remainder being from the coastal mountains and adjacent areas. New records: California : Santa Clara Co. , Mount Hamilton , 6 mi. N. Lick , 7.viii.1968 , leg. A. R. Gillogly (1 TAMU ) ; Missouri , Boone , Ashland Wildlife Ar. , 13.x.1976 , leg. E. G. Riley (2 TAMU ) ; North Dakota , Slope Co. , Sand Creek—East River Road ; 5 mi W Burning Coal Vein , ( 46°35’31’’N , 103°30’1’’W ), 25.vi.2003 , leg. P. P. Tinerella & R. D. Gordon (1 R . D. Gordon ) ; Oklahoma , Grady Co. , Tuttle , 1–30.v.2005 , leg. Brian Baldwin (1 BBC ) ; same locality, 1–30.vi.2005 , leg. Brian Baldwin (3 BBC ) ; same locality, 11.vii.2005 , leg. Brian Baldwin (1 BBC ) ; Latimer Co. , 5 mi. W. Red Oak , 1.v.–1.xii.1980 , leg. K. H. Stephan (1 MCZ ) ; Texas , Kimble Co. , Jct. Llano River & RR 385, 1.iv.2000 , leg. E. G. Riley (911) (1 TAMU ) . Key to the Genera, Subgenera and unusual species of Canada and United States 1. Maxillary palpi very long, much longer than antennae, second palpomere very elongate and slender ( Fig. 1 ).... Hydraena 2 - Maxillary palpi shorter, second palpomere not greatly elongate................................................. 3 2. Posterior ridge of genae well developed; intercoxal segment of abdomen concave, with posterior margin markedly arcuate (see figures in Perkins 1980 ).......................................... Hydraena (Holcohydraena) , H. circulata group - Posterior ridge of genae absent or nearly imperceptible; intercoxal segment flat, with posterior margin straight or weakly arcuate (see figures in Perkins 1980 ).................................................. Hydraena (Hydraenopsis) 3. Body contour evenly curved, pronotum not narrowed posteriorly and surface without impressions ( Fig. 1 )....... Limnebius - Body contour interrupted between pronotum and elytra; pronotum with impressions; pronotum with or without hyaline borders ( Fig. 2 )................................................................................... Ochthebius 4 4. Pronotum without lateral hyaline borders; head without postocular secretion delivery setae; intertidal species, western North America ( Figs. 2 , 9 )............................................................. Ochthebius (s. str.) vandykei - Pronotum with lateral hyaline borders; head with postocular secretion delivery setae ( Figs. 2 , 7 , 8 )..................... 5 5. Lateral hyaline border of prothorax within sinuation behind lateral depression; postocular area with secretion delivery setae blunt, secretion sulcus lacking; splash zone species, eastern North America ( Figs. 2 , 9 )..................................................................................................... Ochthebius (Enicocerus) benefossus - Prothorax with lateral hyaline border extended laterally as far as or beyond lateral depression; postocular area with tapering secretion delivery setae and secretion sulcus ( Figs. 2 , 7–9 )..................................................... 6 6. Pronotum lobate anterolaterally; aedeagus with main-piece apically bifid ( Figs. 1 , 9 )........ Ochthebius (Gymnochthebius) - Pronotum not markedly lobate anterolaterally; aedeagus with pre-terminally inserted process, main-piece not bifid at apex... ................................................................................................... 7 7. Pronotum with sclerotized part sinuate on sides, very shallowly or very deeply; aedeagus with parameres next to main-piece for their entire length, or nearly so; parameres not divergent from main-piece at their bases ( Figs. 2 , 7–9 ).... Ochthebius (s. str.) - Pronotum with sclerotized portion transverse, sides gradually rounded from anterior angles to middle or slightly beyond, then excavate; aedeagus with parameres divergent from main-piece at their bases ( Figs. 2 , 9 )........... Ochthebius (Asiobates)