Sticherus fulvus (Desv.) Ching (1940: 238)

Gonzales, Jasivia & Kessler, Michael, 2011, A synopsis of the Neotropical species of Sticherus (Gleicheniaceae), with descriptions of nine new species, Phytotaxa 31, pp. 1-54 : 24-25

Sticherus fulvus (Desv.) Ching (1940: 238) .

Mertensia fulva Desvaux (1827: 201) . Dicranopteris fulva (Desv.) Underwood (1907: 255) . Type: — JAMAICA. Blue Mts., collector unknown (holotype P!) .

Gleichenia brevipubis Christ (1906: 280) . Sticherus brevipubis (Christ) Smith (1980: 27) . Type: — COSTA RICA. Wercklé s.n. ( lectotype CR!, designated by Lellinger (1977: 713), isolectotype, US!) .

Distribution and ecology: —A northern Neotropical species, widespread in Mesoamerica and the Caribbean: Mexico, Guatemala, Belize, Honduras, El Salvador, Nicaragua, Costa Rica, Panama, Cuba, Jamaica, Haiti, Dominican Republic, Puerto Rico, Guadeloupe, Dominica, Martinique, St. Lucia, and northern Colombia. Generally rather uncommon but it is locally abundant in montane forests, often along roadsides, forming large uniform colonies, at (360–) 1400–2000 m.

Notes: —This is a problematic species that was treated as S. brevipubis by Stolze (1976), Lellinger (1989), Moran (1995), and Mickel & Smith (2004). Sticherus fulvus is closely related and quite similar to S. bifidus , but is recognized by having reduced, rounded to winglike, distinct proximal internal segments, and by its dark or bicolorous, partly darkened buds, branch, and midvein scales. In comparison to S. bifidus , in S. fulvus these scales are fairly short, but with relatively larger cells, resulting in fewer cell rows across the scale bases (<15 cells vs. 15–25 cells in S. bifidus ). The marginal cilia on the bud scales of S. fulvus are also quite characteristic. They are denser and more twisted than those of S. bifidus , which has more delicate cilia. On the darkened scale parts of S. fulvus the cilia are replaced by much shorter, stouter setulae, whereas in S. bifidus and S. ferrugineus such darkened setulae are lacking.

The morphology of the arachnoid scales on the abaxial segment surfaces further shows differences between S. fulvus and the relative closely related species, S. bifidus , S. ferrugineus , S. arachnoideus , S. aurantiacus , and S. brevitomentosus . The arachnoid scales of S. fulvus are shorter and more closely appressed to the segment surfaces than in the other taxa. As a result, the surface scales contrast, at a first glance, with the larger, more spreading scales on the midveins. This is not apparent in the other species. The arachnoid scales of S. fulvus are orangish in color (as indicated by the name), as also seen in S. ferrugineus , S. aurantiacus , and S. brevitomentosus . In contrast. S. bifidus and S. arachnoideus have whitish scales.

The pattern of darkening of the bud scales is geographically variable in Sticherus fulvus ( Stolze 1976) . Populations in Mexico and Costa Rica usually show an apical darkening with distinct dark distal and pale proximal scale portions, whereas populations in Guatemala and the Caribbean islands show a mosaic pattern, with dark cells scattered over the scale surfaces, giving the scales a speckled appearance.

In South America, Sticherus fulvus is generally replaced by S. brevitomentosus , which differs in having translucent margins on the rigid bud scales and often is lacking segments on the 1st branches.

One specimen from Costa Rica (Cartago: Río Grande de Orosí, 1500–1700 m, 10 February 1985, Grayum 5103, MO) appears to be a hybrid between S. fulvus and S. retroflexus . It has slender rhizomes, brittle, glabrous, slightly flexuous branches, linear to hastulate, remotely pectinate segments, and auricular proximal internal segments.