save the Blue Tier
tasmanian liverworts - lejeuneaceae
lejeuneaceae - drepanolejeunea
 Drepanolejeunea aucklandica as epiphyte |
 leaf detail |
This is by far the largest famiy of Australian liverworts comprising of 31 genera with 169 species at last count. Fortunately we have far fewer to contend with in Tasmania.
We begin with a discussion of Drepanolejeunea aucklandica, a minute species that came in with other material. Stem diameter was meassured at around 50µ. We had difficulty observing the details because of extraneous matter adhering to the specimen.
The leaves were rather unusually shaped for a liverwort and the closest match we could find in Meagher & Fuhrer was Nephelolejeunea hamata (now Austrolejeunea h.) but the apparent lack of underleaves led us astray using the Utas key and we identified it as a Radula.
However this was corrected shortly when it was pointed out that the earlier low magnification image did depict underleaves, although this is near invisible to someone not familiar with the species. The darker blobs on stem adjacent to every second leaf is a tiny underleaf. So this was Drepanolejeunea aucklandica, a 'very common epiphyte' in rainforest. It differs from the other possibility, A. hamata in the number of cells attaching leaf to stem.
Subsequently we gained access to a compound microscope and the hidden underleaves were finally revealed - the stubs arising above the stem at every alternate leaf in the second image are part of the Y-shaped underleaves.
Among the more interesting members of this family are the minute epiphyllous liverworts Cololejeunea and Colura which grow on leaves of other plants, usually ferns, although mosses and club-mosses are also known hosts for epiphylls. We are not overly optimistic on ever finding these on account of their minute size, hidden away in the midst of jungles of ferns and mosses. Best we can do for the present is to refer to a page from New Zealand.
lejeunea epiphylla Colenso (non. Mitten)
 Lejeunea epiphylla Colenso |
 leaf arrangement of epiphyllous liverwort |
We wrote the last paragraph prematurely. By sheer accident we came across our first epiphyllous liverwort growing on a hard water fern, Blechnum wattsii, by a roadside stream in mid-December of 2009.
Close examination showed it did not match the better known species of epiphylls; we posted a note to the Bryonet listserver and received a response from New Zealand the next day.
On the basis of the two-celled lobule tooth it was identified as Lejeunea epiphylla Colenso. However we were warned that taxonomy of the genus was in need of revision.
Web
- University of Auckland has some outstanding images of epiphylls
- Reiner-Drehwald of University of Göttingen has a large image collection
of Lejeunea species
- Image of the Lejeunea epiphylla Colenso holotype is available from the New Zealand collection
Page URL: http://www.bluetier.org/Liverwort/lejeuneaceae.htm