The New Zealand Plant Conservation Network

Species

Riccardia multicorpora

Common Name(s)

liverwort

Current Conservation Status

2009 - Sparse

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

Authority

Riccardia multicorpora E.A.Brown

Family

Aneuraceae

Flora Category

Non Vascular - Native

Structural Class

Liverwort

Synonyms

None (first described in 1989)

Distribution

Endemic. North and South Islands.

Features

Dioicous. Plants creeping, often forming extensive populations. Thallus rigid, mid- to dark green, cell walls frequently becoming brown to brownish black in older areas of thallus. Growth indeterminate, branching simply pinnate to bipinnate with minimal tripinnate development, obliquely spreading and alternate to subopposite; main axis and side branches not differentiated but most of side branches growth limited, with the occasional branch showing long continued growth and repeating features of the axis. Thalli 10-15(-30) mm long, 244-347 microns wide. Apices rounded to very slightly cleft. Mucilage papillae 40 x 20 microns, dorsal and ventral persisting for c.1/2 thallus length, not always evident in dried material. Rhizoids ventral, infrequent. Stolons absent. Gemmae not seen. Axis almost plano-convex to biconvex with an acute or rounded margin, 177-195 x 16-215 microns (9-11 cells thick), cells of similar size throughout thallus with their walls only slightly thickened. Dorsal and ventral epidermal and subepidermal cells similar in size. Dorsal epidermal cells almost isodiametric to hexagonally elongate 28-43 x 18-26 microns, and 19-28 microns deep. Ventral epidermal cells of similar shape 19-51 x17-28 microns, and 18-25 microns deep. Dorsal subepidermal cells tending to be more hexagonally elongate, 40-65 x 11-23 microns. Ventral subepidermal cells of similar shape, 32-58 x 13-19 microns. Internal cells (including subepidermal) 15-22 microns deep. Oil-bodies numerous and conspicuous in the dorsal and ventral epidermal cells, granular 0-3 per cell, 8-13 x 5-8 microns, absent from the subepidermal cells. Endophytic mycorrhizae present in lower 3-4 cell layers, occasionally sporadic elsewhere, mycorrhizae c.3 microns wide. Male branches usually solitary or in groups of three, arising from the main axis or on large axial branches, usually sessile but occasionally with a short stalk. Antheridial cavities on dorsal surface in 2-5 pairs separated by 1-2 cells. Female branches solitary or in groups of two, bearing 2-3 pairs of archegonia. Mature Calyptra not seen. Sporophyte unknown.

Fruiting

Fruits not known

Threats

Apparently a widespread, biologically sparse species. Its preferred habitat, montane to alpine restiad-dominated bog is well protected within the New Zealand reserves network.

This page last updated on 20 Oct 2014