Cyclosorus subpubescens (Blume) Ching: A Taxonomic Problem

Abstract

Several points of nomenclature involving Cyclosorus subpubescens (Blume) Ching have been discussed. Herbarium sheets 910327-113 and 908337-179 in the Rijksherbarium, Leiden have been determined as the holotype and isotype of this species respectively. The identification of the specimens in the type cover of the species at Kew Herbarium, as Dryopteris subpubescens (Blume) C. Chr. by Christensen and the description of Cyclosorur subpubescens (Blume) Ching by Ching have been established as erroneous, both characterising Dryopteris pseudoamboinensis Rosenstock (Rosenstock 1917). Holttum (1954) has, however, selected the Sumatran specimen cited under Nephrodium molle var. major (Beddome, 1892) as lectotype for Dryopteris sumatrana v.A.v.R., which name antedates D. pseudoamboinensis Rosenstock and therefore refers to Cyclosorus sumatranus (v.A.v.R.) Ching. A list of herbarium specimens available at Kew Herbarium, London and Rijksherbarium, Leiden and identified to C. subpubescens (Blume) Ching, non sensu Ching is appended and the geographical distribution of this amphidiploid species has been indicated.