Contribution to the bryoflora of Australia, V. Radula tonitrua sp. nov. from Queensland

Abstract

Further study of the two geographic lineages within Radula novae-hollandiae sens. lat. have resulted in the detection of morphological differences among individuals from the Queensland Wet Tropics, and those from New South Wales. Individuals from the Wet Tropics have perianths that are shorter at maturity (1.6-2.0 v. 3.8-4.4 mm), leaf lobes that usually bear numerous marginal gemmae, and leaf-lobules that are smaller and more quadrate. The morphological differences, particularly in perianth length, were not fully appreciated previously and provide evidence supporting the recognition of the Queensland Wet Tropics lineage as a distinct and new species, Radula tonitrua, which is here described. The degree of phylogenetic divergence and fixed molecular difference between R. tonitrua and R. novae-hollandiae, are comparable with the separation observed between R. ocellata and R. pulchella, another species pair exhibiting the same geographic disjunction.