I’d like to introduce a new species of New Zealand fern, Gleichenia inclusisora. Our scientific description was published just before Christmas 2012. The recognition of this species edges the number of native New Zealand fern and lycophyte species nearly to 200.
The specific part of the name, inclusisora, refers to the reproductive structures (the sori) being embedded (included) in a pit within the frond. In other New Zealand Gleichenia species, the reproductive structures sit on the surface of the frond undersides.
Tangle fern is the common name in New Zealand for Gleichenia ferns, and they are so-called because their long, repeatedly-dividing stems grow tangled with one another and other plants.
The new species has a number of features that easily distinguish it from the other Gleichenia species in New Zealand. So why has it not being recognised until now? Well, like their growth-form, their taxonomy (classification and naming) is also tangled, being confusing and neglected. The recognition of Gleichenia inclusisora is easy enough, but more study of the other New Zealand Gleichenia is required, particularly the separation between what we currently call Gleichenia dicarpa and Gleichenia microphylla, as well as on the diversity evident within Gleichenia dicarpa.
Te Papa’s collections, with maps and photos, of:
We suggested Gleichenia inclusisora have a conservation ranking of Naturally Uncommon. It has a scattered distribution, with living populations known from Coromandel and along the South Island’s West Coast. . You’re most likely to encounter it in the Westport-Greymouth area, where populations can be locally extensive.
But please look out for this distinctive species elsewhere; it is quite possible that populations remain to be discovered. Leave a comment below, or email me.
Our description of Gleichenia inclusisora is part of an intensive revisionary effort as we write an eFlora for New Zealand’s ferns and lycophytes. This will comprise a detailed digital guide to these plants. Work in progress will see the number of native ferns and lycophytes recognised in New Zealand top 200 within the next few years; we already know of several more new or otherwise currently unrecognised species.
Some of the eFlora treatments already available for New Zealand ferns:
Blog posts about other new ferns we have described recently: