Phylogenetic reclassification and genitalic morphology of the small water strider genus Nesidovelia Andersen & Weir and allied Microveliinae (Hemiptera: Veliidae)

Phylogenetic analyses of the Australasian Microveliinae is given, including a reanalysis of Andersen and Weir (2003) dataset and an analysis of a new dataset of 46 morphological characters and 42 taxa. Analyses focused on pre- genital, genital and postgenital structures of males and females, including putative male grasping and female anti- grasping structures. Phylogenetic analyses resulted in a redefinition of the genus Nesidovelia Andersen & Weir, with Microvelia (Austromicrovelia) and Microvelia (Barbivelia) erected as junior synonyms, and 29 species included in Nesidovelia, with all but the type species in new combination. Nilsvelia gen. nov. is described to include two species, N. milleri and N. ventrospinosa, both formerly assigned to M. (Austromicrovelia). In addition, we report on the recognition of Papuavelia, Pseudovelia and Tanyvelia as valid genera, distinct from Nesidovelia. We diagnose and describe Nilsvelia, and redescribe Nesidovelia, and provide checklists of the included species for both genera.