Botanic Gardens Trust, Sydney, Australia

Radulaceae

Dr Matt Renner - ABRS Postdoctoral Fellow

The Radula are a genus of liverworts found throughout wetter parts of Australia. The Australian Biological Resource Study (ABRS) funded a project on this genus which has been completed. Three species complexes and one subgenus have been investigated using a combination of molecular and morphological data, being the R. buccinifera, R. parvitexta and R. loriana complexes and subg. Odontoradula. As a result 11 new species are recognised, 4 species are reinstated from synonymy, two newly recorded for Australia, and three excluded from the Australian flora altogether (other name changes involve previous synonyms). The treatment of the R. buccinifera complex has been submitted for publication. The treatment of the R. parvitexta and R. ventricosa complexes is almost ready for submission, and the revision of subg. Odontoradula is in preparation.

Two of the new species are known from single locations, one collected during this study. One new species within subg. Odontoradula is genuinely cryptic. 26 species treatments are more or less completed to date (descriptions, illustrations - line drawings and photographs - specimens examined and curated).

Still to complete are the:

  • treatment of the R. reflexa complex containing somewhere between 7 and 15 entities in Australasia and Oceania, at least one is new and one requires recognition at species level. One species in this complex needs to be excluded from Australia;
  • treatment of the R. lingulata complex, containing fourentities in Australasia and Oceania, one of them new;
  • monograph, including the 10 species whose circumscription is uncontroversial and are not included in one of the above revisions;
  • multi-access key in DELTA, to go online;
  • analysis of mode and tempoof morphological evolution within the genus. The analysis for this paper isdone, and the paper ispartially written; and
  • biogeographic analysis - this is being led bycollaborators overseas.

In total 40 species, 38 of which occur in Australia, plus an unknown number (but at least 5) of entities within the R. reflexa aggregate, will be treated for this project. The Australian Radula flora will settle at c. 43 species, up on the 31 previously listed. This increase is primarily driven by the recognition of species endemic to Australia, particularly the Wet Tropics Bioregion, and/or coastal New South Wales.

Radula-loriana-Castle---M-Renner
Radula loriana Castle from the Wet Tropics Bioregion of Queensland. Until recently this was considered a synonym of the widespread, variable species R. ventricosa Steph. Radula loriana is a common epiphyte on tree trunks or lithophyte on granite boulders in lowland to montane forest. It also occurs in Papua New Guinea, from where the type was collected. Image: Matt Renner