The Australasian genus Schizacme (Loganiaceae): new combinations and new species in the New Zealand flora

Abstract

Schizacme Dunlop (Loganiaceae) is a genus of five perennial subshrubs of predominantly alpine and montane habitats in south eastern Australia and in New Zealand. Schizacme was described as a segregate from Mitrasacme Labill. but combinations in the genus were not made for two New Zealand taxa, Mitrasacme montana Hook.f. var. helmsii Kirk and M. novae-zealandiae Hook.f., thought to be congeneric with Schizacme. By using nucleotide sequence data from the nuclear ribosomal ETS and the chloroplast intron petD, we confirm that New Zealand Mitrasacme and Australian Schizacme form a monophyletic group. New combinations are created in Schizacme and species limits are reviewed, with an emphasis on the New Zealand taxa. Mitrasacme montana var. helmsii is here elevated to species rank, as S. helmsii (Kirk) K.L.Gibbons. Schizacme ciliata K.L.Gibbons is here described as a segregate from S. novae-zelandiae (Hook.f.) K.L.Gibbons. The morphology of Schizacme, including the New Zealand species, is discussed.