Paronychia, Gard. Dict. Abr., ed. 4, 2: . 1754 sec. Bittrich (1993c)
- Type: Paronychia argentea
- =Anychia, Fl. Bor.-Amer. 1: 112-113. 1803 syn. sec. Hartman & al. (2005)
- Type: Anychia dichotoma
In a study mainly addressing Gymnocarpos, Oxelman & al. (2003) found Paronychia to be polyphyletic, with the subgenera Paronychia and Siphonychia forming a strongly supported sister group to Gymnocarpos, whereas species in subg. Anoplonychia were found to be more closely related to Herniaria and Philippiella. This was confirmed by Greenberg & Donoghue (2011). The group consists of 110 (Hartman & al. 2005) or more than 150 species (Bittrich 1993b). It is one of the large groups in the family that has not yet been extensively studied with DNA sequence data, especially in subg. Anoplonychia (only two of 48 species sampled).