Plants 1.5–11.0 cm tall, glossy pale to medium green. Leaves falcate-secund, gradually tapering from an ovate base, 4.7–8.8 mm long, 0.9–1.7 mm wide, canaliculate, smooth; margin serrulate in the upper 15–50 %; border consisting of (1–) 2–6 (–8) cell rows, reaching the serrulate part of the margin or just below or within; costa subpercurrent, with abaxially scattered teeth in the distal part; guide cells 2 (3), with a layer of stereids on either side. Upper laminal cells only slightly shorter than the basal ones, oblong to linear, 12–90 µm long, pitted.

Innermost perichaetial leaf with an acute, obtuse or shouldered apex. Sporogones solitary, very rarely 2 per perichaetium; seta 14.5–29.0 mm long; capsules curved; annulus persistent.

Whereas D. billarderii has often been confused with D. robustum, and the latter has, occasionally, even been considered a synonym, the two are readily distinguished. Apart from those diagnostic characters employed in the key, D. billarderii can be recognised in the field by its ‘untidy’ appearance, caused by the slightly twisted leaf apices. Although there is a slight overlap in all morphological characters, there is sufficient morphological, karyological and molecular evidence to maintain D. billarderii and D. robustum as distinct species.

n = 12, fide Ramsay (1985: 110), Ramsay (2006: 311).

Native.

Occurs in various forest types in eastern New South Wales, Victoria and Tasmania. It is also known from older collections from south-western Western Australia and south-eastern South Australia (not seen); Also in New Zealand, southern and eastern Africa, Madagascar, SubAntarctic Islands and southern South America. Terrestrial or on rocks, logs and tree bases from sea level to c. 1500 m.

Dicranum billarderii Brid., Bot. Zeitung (Regensburg) 1: 214 (1802); Dicranum billarderii Brid., Muscol. Recent. 2: 181 (1798) [pre-Hedwigian name]; Oncophorus billarderii (Brid.) Brid., Bryol. Univ. 1: 401 (1826); Leucoloma billarderii (Brid.) Broth., in H.G.A. Engler & K.A.E. Prantl, Nat. Pflanzenfam. I, 3: 323 (1901); Dicranoloma billarderii (Brid.) Paris, Index Bryol. 2nd edn, 2: 24 (1904). Type: s. loc., [Australia], J.J.H. de Labillardière; holo: B, destroyed; lecto: BM-Bescherelle, fide N. Klazenga, op. cit. 435 (2003); isolecto: L.

Dicranum confine Müll.Hal. & Hampe, in G.E.L. Hampe, Linnaea 28: 206 (1856); Leucoloma confine (Müll.Hal. & Hampe) Broth., in H.G.A. Engler & K.A.E. Prantl, Nat. Pflanzenfam. I, 3: 323 (1901); Dicranoloma confine (Müll.Hal. & Hampe) Paris, Index Bryol. 2nd edn, 2: 25 (1904). Type: Sealers Cove, Wilsons Promontory, Vic., F. Mueller [98]; holo: B, destroyed; lecto: MEL 33140, fide N. Klazenga, loc. cit.; iso: BM, MEL 33125.

Dicranum angustinerve Mitt., J. Proc. Linn. Soc., Bot. 4: 68 (1860); Leucoloma angustinerve (Mitt.) Broth., in H.G.A. Engler & K.A.E. Prantl, Nat. Pflanzenfam. I, 3: 323 (1901); Dicranoloma angustinerve (Mitt.) Paris, Index Bryol. 2nd edn, 2: 24 (1904). Type: s. loc., Tas., W. Archer; holo: NY.

Dicranum austrocongestum Müll.Hal., Hedwigia 36: 356 (1897); Leucoloma austocongestum (Müll.Hal.) Broth., in H.G.A. Engler & K.A.E. Prantl, Nat. Pflanzenfam. I, 3: 323 (1901); Dicranoloma austrocongestum Paris, Index Bryol., 2nd edn, 2: 24 (1904). Type: Fitzroy Falls, near Moss Vale, N.S.W., T. Whitelegge s.n.; holo: B, destroyed; lecto: MEL 29199, fide N. Klazenga, loc. cit.; iso: MEL 33144.

Uncertain Names

?Dicranum pungentella Müll.Hal., Hedwigia 36: 355 (1897); Leucoloma pungentella (Müll.Hal.) Broth., in H.G.A. Engler & K.A.E. Prantl, Nat. Pflanzenfam. I, 3: 323 (1901); Dicranoloma pungentella (Müll.Hal.) Paris, Index Bryol. 2nd edn, 2: 29 (1904). Type: Mt Wellington, Tas., Hb. Melbourne misit; holo: B, destroyed; no isotype located.

?Dicranum weymouthii Müll.Hal., Hedwigia 36: 354 (1897); Leucoloma weymouthii (Müll.Hal.) Broth., in H.G.A. Engler & K.A.E. Prantl, Nat. Pflanzenfam. I, 3: 323 (1901); Dicranoloma weymouthii (Müll.Hal.) Paris, Index Bryol., 2nd edn, 2: 31 (1904). Type: Southdale, Tas., W.A. Weymouth; holo: B, destroyed; no isotype located.

W.A.: south-west, D. Clyne (MEL 1047071).

N.S.W.: Wentworth Falls, Blue Mtns, M. Fleischer 2572 (CANB, L, NY); Gloucester Tops, 42 km WSW of Gloucester, H. Streimann 1543 (CANB, L, MO).

Vic.: summit of Mt William, Grampians National Park, A.C. Beauglehole 21907 (MEL); near Wombelano Falls, Kinglake National Park, A.W. Thies 1480H (MEL); Errinundra Rd, 24 km SE of Bendoc, H. Streimann 39206 (CANB, NY).

Tas.: Standard Hill, 30 km WSW of Deloraine, J.A. Curnow 2181 (CANB, HO, NY); Growling Swallet, Mount Field National Park, N. Klazenga 5496 (MEL); Netherby Creek, 9 km S of Warath, Central Highlands, A. Moscal 13649 (CANB, HO, MEL, NY).

N. Klazenga, Australian Systematic Botany 16: 433, fig. 3a–p; 434, fig. 4a–d (2003); D. Meagher & B. Fuhrer, A Field Guide to the Mosses and Allied Plants of Southern Australia: 141 (2003); R.D. Seppelt, The Moss Flora of Macquarie Island: 137, fig. 54 (2004).

Klazenga, N. (2003). A revision of the Australasian species of Dicranoloma (Bryophyta, Dicranaceae). Australian Systematic Botany 16: 427–471.

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]

Ramsay, H.P. (1985). Cytological and sexual characteristics of the moss Dicranoloma, in Crosby, M.R. (ed.), Studies in systematic botany dedicated to Lewis Anderson, Monographs in Systematic Botany from the Missouri Botanical Garden 2: 93–110.

Ramsay, H.P. (2006). Chromosome numbers in some species of Dicranoloma from Australia, New Zealand and Papua New Guinea. Telopea 11: 308–313.

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]