Fissidens tenellus var. australiensis (A.Jaeger) J.E.Beever & I.G.Stone

Leaves lanceolate; apex acute; vaginant laminae open; margins denticulate throughout. Costa failing 3–4 cells below leaf apex, bryoides-type in cross-section (although an occasional stereid may be seen on the adaxial face).

Perichaetial leaves with distal region of vaginant laminae margins regularly denticulate, vaginant lamina cells little differentiated. Setae 1.8–3.0 mm. Peristome teeth 24–33 µm wide at base, with ornamentation as per species. Calyptra smooth to slightly scabrous. Spores 10–14 µm.

Beever & Stone 1999, fig. 6, n–u; Beever et al. 2002, p. 70, figs 1–6; Catcheside 1980, fig. 20 (as F. tenellus).

Although intermediates with the type variety occur, in its representative form var. australiensis is easily distinguished; it has broader leaf apices with a failing costa, more even serrations on the vaginant lamina margins, smaller vaginant lamina cells, a more or less smooth calyptra, narrower peristome teeth, and larger spores. Distinction at the varietal level is thus appropriate.

Common as an epiphyte or on humic substrates, such as rotting wood, the bases of clumps of Astelia spp., or on decomposing bone; occasionally on soil or rock. It is sometimes found with the only other epiphytic N.Z. Fissidens, F. hyophilus. Additional moss associates include Braithwaitea sulcata, Calyptrochaeta brownii, Dicranoloma menziesii, Haplohymenium pseudotriste, Hymenodon pilifer, Macromitrium spp., and Zygodon intermedius.

Recorded from near sea level to 760 m (Taupō, S Auckland L.D.).