Adiantum pedatum Linnaeus. clade: pedatum clade. Phen: Jun-Aug. Hab: Moist forests and cliffs, especially over calcareous or mafic rocks, sometimes in seasonal seepage. Dist: NS and NB west to ON and MN, south to GA, AL, MS, LA, and OK. Sometimes interpreted to also be present in e. Asia; Lu et al. (2011) make clear that Asian material should be treated as two species distinct from Adiantum pedatum; Adiantum japonicum was named in 2021 (Zhao et al. 2021).
Origin/Endemic status: Native
Taxonomy Comments: Plants growing on serpentine in MD and se. PA have sometimes been interpreted as being A. aleuticum, but recent molecular studies show that they are "stunted forms" or "sun forms" of A. pedatum (Williams, Theis, & Hoess 2016).
Synonymy: = Ar, G, GrPl, Il, K4, NE, NY, RAB, S13, Sf, Tat, Tn, Va, W, WV, Lu et al (2011), Paris (1991), Zhao et al (2021a); = Adiantum pedatum L. var. pedatum – F, Mo1; > Adiantum aleuticum (Rupr.) C.A.Paris – FNA2, Pa, misapplied to MD and PA material; > Adiantum aleuticum (Rupr.) C.A.Paris var. aleuticum – K3, misapplied to MD and PA material; < Adiantum pedatum L. – FoC; > Adiantum pedatum L. – FNA2, K3, Pa; > Adiantum pedatum L. ssp. calderi Cody – C, misapplied to MD and PA material; > Adiantum pedatum L. ssp. pedatum – C