Description of the first- and third-instar larvae of Hydrocanthus levigatus (Brull, 1837) (Coleoptera: Noteridae)

We describe the first and third larval instars of Hydrocanthus levigatus (Brulle, 1837), including morphometric and chaetotaxic analyses of the cephalic capsule, head appendages, legs, last abdominal segment, and urogomphus. Larvae of this species have many dark dorsal maculae on the body, similar to those of H. socius Sahlberg, 1844 and H. debilis Sharp, 1882. First instar larvae of H. levigatus can be separated from those of H. socius and H. debilis by the following combination of characters: large size and seta TI5 somewhat longer than tibial length on mesothoracic and metathoracic legs. Conversely, the third instar of H. levigatus differs from those of H. socius and H. debilis in the greater number of secondary setae on the legs.