Grapefern

Description

Rhizomes erect,unbranched. their apex 2-5 cm below the soilsurface, bearing 6-22 (ave. 14) fleshy roots;gemmae absent. Above-ground plants 6-12(ave. 9) cm tall with a common stalk 0-3 (ave.1.5) cm long. Trophophores yellow-green, leathery; stalks 0-1 cm long; blades 2.5-7(ave. 4) cm long, 2-4 (ave. 3) cm wide,narrowly ovate to ovate, once pinnate. Pinna pairs 4-6, more or less perpendicular to the rachis, separated to slightly overlapping, not overlapping the rachis. Basal pinnae 7-20 (ave. 13) mm long, 7-18 (ave. 12) mm wide,sessile, fan-shaped spanning an arc of 120-180o, often asymmetrical, with the basal portion expanded; basiscopic inner margins straight to shallowly concave; outer pinna margins entire or occasionally incised or lobed with rounded sinuses;veins dichotomous, 3-5 major veins entering the pinna base, 45-55 veins ending at the margins.Sporophores 5-10 (ave. 7) cm long; sporophore stalks 2.5-5 (ave. 4) cm long and shorter than or equaling the length of the trophophore; sporangia-bearing portion erect, 1-2-pinnate, broadly ovate in outline, branches 4-6, ascending to spreading, especially the lowermost, which are often twisted such that the sporangia project downward; sporangia partially embedded in the distally thickened sporangiophore branches. Spores 38-42 (ave. 40) -m in longest diameter, released later than those of B. lunaria var. lunaria. Apparently diploid. (Stensvold, Farrar and Johnson-Groh 2002).