Publication: Sp. Pl. 2: 979. 1753 (as vesicariu).
selected vouchers: WTU
Notes: FNA23: "Carex vesicaria hybridizes with C. saxatilis and, very rarely, with C. hystericina and C. utriculata.
Carex vesicaria as here treated broadly as a variable circumpolar species. K. K. Mackenzie (1931–1935) recognized a small segregate, Carex raeana Boott, but specimens referred here are either depauperate C. vesicaria or hybrids. T. V. Egorova (1999) recognized C. vesicaria as a Eurasian and North American species but also recognized a primarily North American C. monile, occuring locally in Asia as well. The two species were differentiated by characteristics of perigynium length and width, pistillate spike size, and beak and beak teeth size and proportions. The North American material is so variable in perigynium size and shape and inflorescence size that recognizing the two entities seems difficult. Further study of variation in North American material and the relationships of North American and Eurasian material are needed. Indeed, the complex is in need of detailed systematic study on a worldwide scale."