Plants small, yellow-green; sterile shoots 2–10 mm long, often growing from the base of a female plant. Stems slender, elongate; in section with a narrow central strand of small thin-walled cells; rhizoids basal. Leaves distant, in 6–20 or more pairs, cultriform, 0.2–0.5 mm long, 0.1–0.2 mm wide; apex sharply recurved, acute; laminae unistratose; margins entire to serrulate; vaginant laminae reaching to 3/4–4/5 leaf length, partly or fully open, elimbate except on largest leaves, where present, limbidium of 3–6 rows of narrow elongate cells; dorsal lamina elimbate, failing above the insertion to short-decurrent. Costa of bryoides-type, percurrent to excurrent. Lamina cells smooth, small, irregularly quadrate to polygonal, c. 8–10 µm wide, ±rectangular and up to 20 µm long proximally in the vaginant laminae.

Dioicous. Fertile plants 2–5 mm long, the leaves cultriform or straight, to c. 1 mm long, 0.25–0.30 mm wide. Perichaetia terminal; perichaetial leaves to 1.5 mm long, the costa percurrent to excurrent; limbidium of vaginant laminae broad below, narrowed above, often just extending into the apical lamina. Setae terminal, flexuose, 7–15 mm long. Capsules asymmetrical, curved; theca c. 0.6 mm long; exothecial cells short-rectangular, thin-walled, the corners not or weakly collenchymatous. Calyptra not seen. Operculum short-rostrate. Peristome of bryoides-type. Spores 12–17 µm diameter.

Occurs in southern Western Australia, south-eastern South Australia, eastern New South Wales, southern Victoria and on the west coast of Tasmania. Also in South Africa.

Fissidens bifrons Schimp. ex Müll.Hal., Bot. Zeitung (Berlin) 17: 198 (1859). Type: Cape of Good Hope, South Africa, Breutel; iso: BM.

Taxonomic synonym

Fissidens bryoidiodes Broth., Proc. Linn. Soc. New South Wales 41: 576 (1916). Type: s. loc., N.S.W., W.Forsyth 676; holo: H-BR; iso: MEL, NSW.

Misapplication

[Fissidens splachnifolius auct. non Hornsch.: D.G.Catcheside, Mosses of South Australia 76 (1980)]

W.A.: Hoves Falls, Forrest Natl Park, I.G.Stone 6202B (MEL).

S.A.: Bellevue Heights, near Adelaide, D.G.Catcheside 75.78 (AD).

N.S.W.: Penshurst, W.Forsyth 679 (NSW).

Vic.: Tallarook, I.G.Stone 9318 (MEL).

Tas.: West Coast, road to Arthur Creek, I.G.Stone 25275 (MEL).

Fissidens bifrons varies greatly in size, depending on the habitat. It often has delicate flagelliform innovations, consisting of alternating sequences of minute and very distantly set leaves and larger cultriform leaves, arising from within the terminal perigonia, perichaetia or leaf axils.

Magill (1981) regarded F. bifrons as a synonym of F. pygmaeus Hornsch., but the latter has non-arcuate, ±asymmetrical capsules, short setae (c. 3–5 mm long), larger spores, and small vegetative leaves bordered on the vaginant laminae.

D.G.Catcheside, Mosses of South Australia 76, fig. 16. (1980), as F. splachnifolius.

Magill, R.E. (1981). Flora of Southern Africa. Bryophyta. Part 1. Mosses. Fasc. 1. Sphagnaceae–Grimmiaceae. (Botanical Research Institute, Department of Agriculture & Fisheries, Pretoria).

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.