Plants robust, 5–40 mm long, dark green, forming tufts, semi-aquatic or terrestrial. Stems simple or branched, with minute axillary nodules; in section with a central strand of small thin-walled cells. Leaves in numerous pairs, homomallous, curled when dry, elliptical to obovate, 1.1–2.0 mm long, 0.3–0.7 mm wide; margins ±smooth or weakly serrulate; apex obtuse, apiculate; limbidium almost reaching the leaf apex, mostly unistratose, biseriate, up to 5 rows wide in the vaginant laminae, outer cells rectangular to quadrate proximally; vaginant laminae reaching 1/2–3/4 leaf length, ±closed; dorsal lamina usually slightly decurrent; laminal cells smooth, hexagonal, firm-walled, 11–15 µm wide, larger juxtacostally and 20–25 × 10–12 µm at the base of the vaginant laminae. Costa percurrent, modified bryoides-type; all cells thin-walled.

Dioicous or synoicous. Perigonia terminal (not seen). Perichaetia terminal; perichaetial leaves more acuminate than vegetative leaves, (1.5–) 1.9–3.0 mm long. Setae 4–10 mm long. Capsules suberect, asymmetrical; theca oblong, 0.8–1.5 mm long, 0.4–0.8 mm wide. Operculum 0.3–0.7 mm long, sharply conical. Peristome bryoides-type; teeth c. 50–90 μm wide at the base. Calyptra not seen. Spores 17–26 µm diameter.

Native.

Occurs in Northern Territory, South Australia, Queensland, New South Wales, Australian Capital Territory, Victoria and Lord Howe Island. Also in the Solomon Islands, New Caledonia and the Kermadec Islands.

Fissidens dietrichiae Müll.Hal., Linnaea 37: 146 (1872). Type: Brisbane River, Qld, A.Dietrich 444; holo: S (n.v.); iso: BM, MEL, NY.

Taxonomic synoyms

Fissidens undatodecurrens Müll.Hal., Enum. Bryin. Exot. 90 (1989). Type: Ashgrove, near Brisbane, Qld, May 1885, H.Tryon; iso: MEL.

Fissidens praemollis Broth., Proc. Linn. Soc. New South Wales 41: 578 (1916). Type: Skinners Head, Richmond R., N.S.W., 1901, W.W.Watts 5371;  holo: H-BR; iso: MEL, NSW.

Fissidens densifolius Broth., Queensland Bot. Bull. 4: 21 (1891), nom. nud. Based on: Mt Perry, Qld, J.Keys (?); MEL.

Fissidens sydneyensis Geh., Proc. Linn. Soc. New South Wales, Suppl. 27: 29 (1902), nom. nud. Based on: Minto, near Sydney, N.S.W., T.Whitelegge 263; MEL.

Misapplication

[Fissidens crassipes auct. non Wilson ex Bruch & Schimp.: G.A.M.Scott & I.G.Stone, Mosses of Southern Australia 96 (1976)]

N.T.: Reedy Rock Hole, George Gill Range, A.C.Beauglehole 20937 (MEL).

S.A.: Clarendon, J.O.Tepper 587 (NY).

Qld: Cania Gorge Natl Park, I.G.Stone 20941A (MEL).

N.S.W.: Hickeys Falls, S of Coonabarabran, I.G.Stone 8408B (MEL); Hanging Rock Ck, Barkers Vale, H.Streimann 6141 (CANB).

A.C.T.: Uriarra Crossing, Murrumbidgee River, D.G.Catcheside 64.82 (AD).

Vic.: Yarra River at Heyington Railway Stn, J.H.Willis 154 (BM, MEL).

M.A.Bruggeman-Nannenga, Proc. Kon. Ned. Akad. Wetensch., ser. C, 82: 23, fig. 5 (1979); D.G.Catcheside, Mosses of South Australia 73, fig. 13 (1980), as F. crassipes.

Beever, J.E. (2014) Fissidens leptocladus, in Moss Flora of New Zealand eFlora. http://www.nzflora.info/index.html

Bruggeman-Nannenga, M.A. (1979). The section Pachylomidium (genus Fissidens) II. The species of central America, temperate South America (including the high Andes), Australia, New Zealand and New Guinea. Proc. Kon. Ned. Akad. Wetensch., ser. C, 82: 11–27.

Catcheside, D.G. (1980). Mosses of South Australia. (Government Printer, Adelaide).

Scott, G.A.M. & Stone, I.G. (1976). The Mosses of Southern Australia. (Academic Press, London).

Seppelt, R.D. & Stone, I.G. (2016). Australian Mosses Online 70. Fissidentaceae. Australian Biological Resources Study, Canberra. Version 16 June 2016. http://www.anbg.gov.au/abrs/Mosses_online/70_V2_Fissidentaceae.html

For more details about the history of this treatment see Fissidentaceae profile.