A New Form of Asplenium montanum from New York

On the Shawangunk Mountain ridge in Ulster County, New York, on September 18, 1973, I discovered 60 fronds of an unusual Asplenium growing in a fissure on a vertical cliff of Silurian conglomerate. Asplenium montanum Willd. is abundant on these cliffs. I have observed numerous living plants of Asplenium montanum in Ulster County, New York, in seven counties in North Carolina, and I have seen herbarium specimens at the New York Botanical Garden (NY). All specimens were found to be uniform in morphology, and more than 99 per cent of the fronds bore sori. There are no described forms or varieties of this species. The new form (Fig. 1) differs from the typical form in the following characters: (1) blades light yellow-green instead of dark blue-green, (2) tip of frond not tapered to a lobed apex (Fig. 2A versus 3A), (3) pinnae and ultimate divisions more dissected (Fig. 2B versus 3B), (4) frond length averages 2.3 cm shorter than typical New York specimens, and (5) the absence of sori. The possibility of ecological variation is minimal, as plants of the typical species grow on the same cliffs and even on both sides of the new taxon in the same rock fissure. These differences warrant naming this a new form of Asplenium montanum. Asplenium montanum f. shawangunkense Reeves, f. nov. Ab Asplenio montano f. montano lamina flavo-virenti sterili, apice non lobato, et pinnis lobisque incisioribus differt. HOLOTYPE: Between Lake Minnewaska and Mohonk Lake in the Shawan