Asplenium trichomanes subsp. quadrivalens

Spores (as measured in Hoyer's Solution) 37--43 µm. 2 n = 144.

Calcareous rocks such as limestone and dolomite; 0--3000 m; B.C., Ont., Que.; Conn., Del., Ill., Maine, Md., Mass., Mich., N.H., N.J., N.Y., Ohio, Oreg., Pa., Vt., Va., Wash., W.Va., Wis.; Europe; Asia; Africa; Pacific Islands in New Zealand; Australia.