THE SYSTEMATICS OF THE BURROWING WATER BEETLES (COLEOPTERA: ADEPHAGA: NOTERIDAE)

Abstract

The aquatic beetle family Noteridae (Coleoptera: Adephaga) comprises a group with poorly studied diversity that has received limited systematic study. Despite the corroboration of multiple phylogenic reconstructions, many relationships within Noteridae remain poorly supported or unresolved. Here I address the questions surrounding the systematics of Noteridae in three ways. First, a review of previously constructed noterid phylogenies is presented and methods, variation in recovered relationships and the current classification of Noteridae are explored. Second, a phylogeny of Noteridae is inferred based on the analysis of DNA sequence data of five gene fragments: COI, H3, 16S, 18S, and 28S. Our taxon sampling of Noteridae is the most robust of any phylogenetic investigation of Noteridae to date and includes representatives for 16 of the 17 current noterid genera. Bayesian and Maximum likelihood analyses produce highly supported trees that strongly contradict previous studies. Our results recover the monophyly of the following higher level groups: (1). Meruidae + Noteridae, though the exact nature of this relationship is unresolved; (2) Phreatodytinae + Notomicrinae; and (3) Noterinae. All known genera are found to be monophyletic except Hydrocanthus Say, found paraphyletic with respect to Mesonoterus Sharp and Prionohydrus Gomez & Miller, and Suphisellus Crotch, found to be paraphyletic with respect to Pronoterus. Thus the following changes in classification and taxonomy are proposed: the subgenus Sternocanthus Guignot is resurrected from synonymy stat. rev. and elevated to the genus rank stat. n. to contain Old World members of the genus Hydrocanthus sensu lato; and Pronoterus Sharp syn. n. is placed in synonymy with Suphisellus Crotch. All tribes within the Noterinae are recovered as paraphyletic or invalid due to synonymy and the a revised classification is thus proposed: (1) Noterini Thomson sensu n. is redefined contain the genera Noterus Clairville and Neohydrocoptus Satô, thus including Neohydrocoptini Zalat et al. syn. n. as a junior synonym ;(2) Tonerini Miller sensu n. is redefined to hold the genera Synchortus Sharp, Tonerus Miller, and Liocanthydrus Guignot; (4) Renotini trib. n. is erected to contain the genus Renotus Guignot; (5) Suphisini Sharp rev. stat. is resurrected from synonymy to hold the genera Suphis Aubé, Canthysellus Baca & Toledo gen. n., Suphisellus Crotch incl. Pronoterus Sharp, and a tentative new noterid genus; and (6) Hydrocanthini Sharp stat. rev. is resurrected from synonymy to hold the genera Canthydrus Sharp, Sternocanthus Guignot, Hydrocanthus Say, Mesonoterus Sharp and Prionohydrus Gomez & Miller. A discussion of relationships, classification and morphology is presented. Finally, the poor documentation of noterid diversity is addressed with the description of the genus Canthysellus Baca & Toledo gen. n., here erected to contain three species Canthysellus buqueti (Laporte, 1835), C. sipaliwini sp. n. and C. peruanus sp. n. Descriptions, diagnoses, illustrations of diagnostic characters and a key to species of Canthysellus are provided.