Genus Hydrophilus - New World

DibolocelusAbdomen with glabrous region limited to the medial line of ventrites 3-5 [Abb. 1]. Prosternum divided into lateral halves for the reception of the anterior portion of the sternal keel. Dorsal surface sometimes appearing greenish. Subgenus

→ 2-Abdomen with glabrous region not limited to medial line of ventrites 3-5. Prosternum strongly emarginated posteriorly bul not divided into lateral halves. Dorsal surface never appearing greenish. Hydrophilus s.str.

ensifer Brullé, 1837Habitus [Abb. 2]. Specimens usually smaller (<32 mm). Collectively, the glabrous regions of ventrites 2-5 from a distinctive "kite" shaped glabrous region [Abb. 3]. Aedoeagus [Abb. 4]. Widespread from Mexico to Argentina, but not yet known from the Nearctic region.

→ 3-Specimens usually larger (>34 mm). Abdominal pubescence broad, nol forming a "kite" shaped glabrous region on ventrites 2-5.

triangularis Say, 1823Habitus [Abb. 5]. Antenna! cupule with little to moderate elongation ca. l.2-2x as long as wide. Abdominal glabrous region as in [Abb. 6]. Fifth protarsomere of the male expanded [Abb. 7], but with a distinctly obtuse angle. Aedoeagus [Abb. 8]. Continental United States, southern half of Canada, and northern Mexico.

insularis Castelnau, 1840-Habitus [Abb. 9]. Antennal cupule greatly elongated ca. three times as long as wide. Abdominal glabrous region as in [Abb. 10]. Fifth protarsornere in males greatly expanded [Abb. 11], the plate exhibiting a nearly right angle. Aedoeagus [Abb. 12]. Arizona, California, Texas, and Florida in the United States, Mexico, Central America, West Indies, and northern South America.