Lindsaea quadrangularis Raddi

• Authority

  Mickel, John T. & Beitel, Joseph M. 1988. Pteridophyte Flora of Oaxaca, Mexico. Mem. New York Bot. Gard. 46: 1-580.

• Family

  Lindsaeaceae

• Scientific Name

  Lindsaea quadrangularis Raddi

• Description

  Species Description - Rhizome short-creeping, 1.5-3 mm diam.; rhizome scales castaneous, 1-2 mm long, 0.3 mm wide; fronds 15-40 cm long, clumped; stipe ½-2/3 the frond length, yellow or brown at base, grooved, glabrous; rachis at insertion of basal pinnae strongly angular abaxially, rest of rachis grooved beneath; blade bipinnate, 1-4 pairs of alternate to subopposite pinnae; pinnae with 1540 pairs of segments, mostly 12-18 mm long, 58 mm wide, glabrous; veins 1- or 2-forked; indusium 0.5 mm wide, margin subentire.

• Discussion

  Lindsaea lancea (Linnaeus) Beddome var. quadrangularis (Raddi) Rosenstock, Hedwigia 46: 80. 1906. Type. Brazil. Vic. Rio de Janeiro, Raddi s.n. (PI). Kramer (1957) recognized four subspecies of L. quadrangularis, of which two occur in Oaxaca. He commented that ssp. antillensis was the most distinct of his four subspecies and that there would be no objection to treating it as a species. He distinguished the two subspecies in the following manner: 1. Secondary rachises pale, abaxially with a groove starting abruptly above the subterete base. ssp. antillensis. 1. Secondary rachises with pale ± wing-like margins bordering a dark concave or flat central portion. ssp. subalata.