S. Mahunka szerk.: Folia Entomologica Hungarica 57. (Budapest, 1996)

with a longitudinally impressed latero-basal stria at both sides. Pronotal striae continuing on elytra as discal striae. Scutellum hidden. Elytra with a longitudinally impressed discal stria each reaching at least the elytral middle, also with distinct but posteriorly more or less reduced parasutural striae; surface with very fine and dense punctuation. Epipleura broad at base, abruptly narrowed at the middle, hence narrow to apex, without a distinct basal cavity and without a diagonal carina crossing near base. Pro- and mesotarsi pseudotetramerous. The following key is given to the determination of the tribes and genera of the subfamily Hydroporinae. The species-groups of the large genera Hydrocoptus and Hydroporus are also included. 1 (42) Pronotum without a longitudinally impressed latero-basal stria at both sides. Apex of metacoxal processes (in lateral view) protruding from abdominal plane like a step. 2 (41) Clypeus truncate, straight or barely emarginate anteriorly — Hydroporini (Aubé, 1836). 3 (38) Last segment of labial palpi truncate apically, barely emarginate at tip. 4 (11) Metacoxal processes distinctly separated from each other at apex by an angular median emargination. (Sometimes metacoxal cavities separated from each other by an exposed interlaminar bridge of coxal processes. In this case median emargination not so evident, appears to be split into two lateral indentations by interlaminar bridges.) 5 (10) Metacoxal processes without an exposed interlaminar bridge; coxal cavities contiguous; median emargination undivided. 6 (9) Ventral side finely granulated; surface, in a major part, resembling a file and fairly dull; granulation frequently evanescent in abdominal median line. 7 (8) Elytral surface alutaceous, without reticulation Deronectes Bedel, 1881 8 (7) Elytral surface distinctly reticulated [Oreodytes Seidlitz, 1887] 9 (6) Ventral side simply punctuated; surface, in a major part, smooth and glossy, vaguely reticulated near sides Rhiacodytes gen. n. 10 (5) Metacoxal processes with an exposed interlaminar bridge separating coxal cavities, splitting median emargination into two lateral indentations [Bartheus Houlbert, 1934] 11 (4) Metacoxal processes not separated from each other at apex. 12 (13) Body outline conspicuously discontinuous; pronoto-elytral angle clearly marked. Elytral margin (in lateral view) strongly arched at shoulder. Prosternai process fusiform, broad, slightly convex, not compressed laterally. Metacoxal surface dull Suphrodytes Des Gozis, 1914 13 (12) Body outline more or less continuous; pronoto-elytral angle poorly marked. Elytral margin (in lateral view) less strongly arched (either distinctly or barely bent) at shoulder. Prosternai process spatuliform or lanceolate, narrow, subcarinate, more or less compressed laterally. Metacoxal surface more or less glossy.