The New Zealand Plant Conservation Network

Species

Fissidens rigidulus var. pseudostrictus

Etymology

Fissidens: From the Latin fissio 'fission' and dens 'tooth, prong' meaning split tooth and referring to shape of the lamina.

Common Name(s)

moss

Current Conservation Status

2009 - At Risk - Naturally Uncommon

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Qualifiers

2009 - DP, RR, Sp

Authority

Fissidens rigidulus var. pseudostrictus J.E.Beever

Family

Fissidentaceae

Flora Category

Non Vascular - Native

Structural Class

Moss

Distribution

Endemic. New Zealand: North, South and Chatham Islands(from Te Paki south to about Taupo with one record from the Wairarapa, thence recorded once from Nenthorn Otago and once again from Rangiauria (Pitt Island) in the Chatham Islands group).

Habitat

Saxicolous on base rich rocks such as basalt or chlorite schist with one record from ignimbrite. Lowland usually in densely forested areas. A rheophyte usually growing completely immersed in fast flowing streams (often under waterfalls and in similar steep sections of narrow streams). Often found growing sympatrically (most often syntopically) with Fissidens rigidulus var. rigidulus and F. waiensis.

Features

Plants medium-sized for the genus, saxicolous, aquatic, dark green to black, shoots 5.0–30.0 x 1.5–2.5 mm, branched ; shoot branches readily detached, rhizoids at base of shoot branches and well developed in axils of older leaves; leaves in 10–50 pairs, straight to falcate when moist, little altered when dry, broadly lanceolate, 1 .5–3 .0 x 0.30–0.75 mm, acute; vaginant lamina 2/3 of leaf length; extending across the lamina to a variable degree; dorsal lamina reaching to stem; costa failing about 4 cells before leaf apex, surface cells moderately broad-lumened, deuter cells exposed on the adaxial face; leaf margins entire to very weakly crenulate; border of prosenchymatous cells absent or variably developed on margin, or intramarginally, on vaginant laminae, extending in some cases onto apical and dorsal laminae ; apical, dorsal, and vaginant laminae variably bi- to pluristratose; lamina cells irregularly quadrate to hexagonal, medium thick-walled, 7.5–22 µm long, smooth, larger near the costa and often covering the costa in proximal part of the leaf. Apparently dioicous; male inflorescences terminal on main or axillary shoots; female inflorescences and sporophytes not seen.

Fruiting

Fruiting material has not yet been seen

Threats

Fissidens rigidulus var. pseudostrictus is still relatively poorly known but opportunistic survey suggests that it is not very common (though it can be locally abundant in a very few locations), and rather sparsely distributed. It is seemingly absent from large parts of the country despite an abundance of suitable habitat. Currently no specific threats have been identified although it seems likely that this moss requires reasonably clean, fast flowing water, ideally within forested habitats - though it has been found in urban Auckland and also within a stream flowing through tussock grassland in Otago.

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 25 Jul 2014