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1 Rhizome short, erect; all the pinnae interconnected by orbicular auricles or triangular wings between the pinnae; leaf blade lanceolate, > 4× as long as wide, tapering to both ends from near the middle (the largest pinnae near the middle of the blade); primary pinnae alternate
..2 Rachis wings present between the two basal pinna pairs; basalmost pinnae (2-) ca. 3× as long as wide; frond blade usually wider than long; rachis bearing on its lower surface relatively few, white to pale tan, narrowly lanceolate scales (these mostly 3-5 cells wide at the base) and hairs 0.1-0.25 mm long
....3 Clones/colonies fairly compact, often dense with overlapping fronds; fronds shorter; lowermost pinnae relatively wide (ca. 4× as long as wide), often strongly deflexed and projecting forward from the plane of the upper frond; the overall shape ovate with a long-acuminate tip; spores smaller, average < 60μm; [n = 3n = 90]
....3 Clones/colonies often loose, fronds touching but not overlapping; fronds taller; lowermost pinnae relatively narrow (4.5× or 5× as long as wide), somewhat but not strongly deflexed and not projecting as far forward; overall blade shape deltate (triangular, but again with a long tip) and less rounded at bottom; spores larger, average > 60μm; [n = 4n = 120]