Una nueva especie de Adiantum (Pteridaceae) de México

As a result of the collection of ferns and lycophytes in the Huasteca potosina of Mexico, a new species of Adiantum is described and illustrated. Adiantum aquismonense has morphological and anatomical features that distinguish it from Adiantum tricholepis and Adiantum feei. In particular, A. aquismonense has reddish-brown hairs and its geographical distribution tends towards the slope of the Gulf of Mexico. In contrast, A. tricholepis has hyaline hairs, and while A. feei has reddish hairs similar in color to those of the new species, they are shorter. All three species are found in Mexico. Anatomically, the fusion of vascular bundles of the petiole in A. aquismonense occurs distally in the petiole, whereas in A. tricholepis it occurs in the middle of the petiole. The spongy parenchyma of the leaves is more compact in A. tricholepis than in A. aquismonense.