Plants to c. 5 cm tall, light green. Stems erect, simple to sparingly branched; asexual propagules absent. Leaves falcate-secund, ovate-linear, gradually long-acuminate, 4.0–11.2 mm long, 0.4–1.1 mm wide, canaliculate, smooth; margin serrulate at the extreme apex or in the distal 20%, crenulate or entire below in upper 50–75 %, entire below; border consisting of 1–4 cell rows, reaching 20–33 % of the leaf length; costa excurrent, abaxially smooth throughout or with a few minute teeth at the extreme apex; guide cells 7–14, with (1–) 2 or 3 layers of stereids on either side; abaxial epidermis differentiated, consisting of cells with distinct lumina, in the distal part of the leaf. Upper laminal cells conspicuously shorter than basal ones, isodiametric to oblong, rectangular to irregularly shaped, 10–35 µm long, not pitted.

Innermost perichaetial leaf abruptly contracted into a long subula. Sporogones solitary; seta 20–39 mm long; capsules straight; annulus persistent; peristome teeth split to the base, very fragile.

When not bearing sporogones, H. trichopodum is very difficult to distinguish from Dicranoloma menziesii. The most reliable gametophytic characters are probably the narrower leaves and the smooth costa of H. trichopodum, which may have only a few small teeth at the extreme apex, while D. menziesii has small scattered teeth in the distal quarter or more of the costa. In contrast, the two species are readily distinguished in the presence of sporogones.

Native.

Occurs in western Tasmania. Also in New Zealand. Grows in wet forest, usually quite high on tree trunks.

Dicranum trichopodum Mitt., in J.D. Hooker, Handb. New Zealand Fl. 2: 411 (1867); Dicranoloma trichopodum (Mitt.) Broth., in H.G.A. Engler & K.A.E. Prantl, Nat. Pflanzenfam. 2nd edn, 11: 209 (1924); Holomitrium trichopodum (Mitt.) Klazenga, J. Hattori Bot. Lab. 100: 301 (2006). Type: Otago, South Island, New Zealand, Hector & Buchanan; holo: NY.

Tas.: Hartz Mountains Rd, Arve River area, W of Geeveston, P.J. Brownsey M26063b (HO); near Pelion Plains, Cradle Mountain-Lake St. Clair National Park, S.J. Jarman s.n. (HO 513156); Red Knoll, 0.5 km W of Scotts Peak Dam, Southwest National Park, A. Moscal 28138A (HO).

The gametophore of H. trichopodum does not fit well in Holomitrium, because the leaves are not at all spirally contorted when dry, being more similar to a Dicranoloma gametophore. However, sporogone characters, supported by DNA sequences, clearly place it in this genus.

Holomitrium austro-alpinum E.B.Bartram from New Guinea also has stiff leaves that are not much altered when dry.

N. Klazenga, Australian Systematic Botany 16: 466, fig. 29a–h (2003), as Dicranoloma trichopodum.

Klazenga, N. (2012). Australian Mosses Online 33. Dicranaceae. (Australian Biological Resources Study: Canberra). Version 30 May 2012; https://www.anbg.gov.au/abrs/Mosses_online/33_Dicranaceae.html [Accessed July 2019]

Klazenga, N. (2012). Australian Mosses Online 33. Dicranaceae. (Australian Biological Resources Study: Canberra). Version 30 May 2012; https://www.anbg.gov.au/abrs/Mosses_online/33_Dicranaceae.html [Accessed July 2019]