Pellaea calidirupium — a new fern species from New Zealand

Abstract

Abstract Pellaea calidirupium sp. novo occurs in dry, rocky places east of the main divide from Cook Strait to central Otago, with an outlying population on Rangitoto Island. It is distinguished from P. rotundifolia and P. falcata by its appressed stipe and rachis scales, triangular or falcate pinnae, widely spaced and stalked lower pinnae, and sori which are continuous around the pinna apices. All three New Zealand species have a chromosome number of n = 58. Pellaea calidirupium is ecologically separated from P. rotundifolia which occupies damper and more shaded habitats. Nevertheless, P. calidirupium and P. rotundifolia are often contiguous and wild hybrids occur in such sites. The relationship of all three New Zealand species to Australian taxa requires further investigation.