Sticherus arachnoideus Østergaard & Øllgaard (2001:121)

Type: — ECUADOR. Zamora-Chinchipe: Río Sabanilla, at hydroelectric plant 1.5 km W . of Sabanilla, 1800 m, Øllgaard 100745 (holotype AAU!, isotypes NY!, UC!, US!).

Distribution and ecology: —Locally common in the Andes of Colombia (Caldas) and southwestern Ecuador (Loja, Morona-Santiago, Zamora-Chinchipe) at 1300–2700 m. Probably also occurs in Venezuela. S. arachnoideus can be found growing in montane forests, clearings, on ridges, and along roadsides, often forming mixed colonies with S. tomentosus .

Notes:— A little-known species that is recognized by the linear, ultimate branches with uniform segments, and by lacking segments and bearing simple aphlebiae on the 1 st and the 2 nd branches. The abaxial surfaces have dense, whitish indument, especially on the branches, where the scales overlap. The scale pattern is similar to that of S. antillensis but the scales of S. arachnoideus are generally more translucent with more numerous, delicate, and bear longer marginal cilia. Another difference between these two is the relative length and segment disposition of the branches. In S. arachnoideus, the basal two branches lack segments and are of roughly similar length, whereas in S. antillensis they are pectinate (at least the 2 nd branch) and the 2 nd branch is conspicuously longer than the 1 st, and may even approach the length of the distal branch.