Radula buccinifera (Hook. fil. & Taylor) Gottsche, Lindenb. & Nees

[from NY00831294 and MEL38047] Forming interwoven mats of shoots, brown in herbarium, shoot systems regularly pinnately branched, with additional pseudodichotomous branching due to production of pairs of subfloral innovations below gynoecia; dimorphic, primary shoots 1.2–1.7 mm wide and up to 40 mm long, secondary shoots smaller in stature and either apparently terminating growth after five to seven leaf pairs, or continuing vegetative growth and attaining similar stature to primary shoots by fourth to sixth pair of leaves; older shoot sectors retaining leaf-lobes. Stems 130–155 µm diameter, with cortical cells in a single tier of 25–31 rows, medulla cells in 20–35 rows, cortical cell walls yellow-brown pigmented, ventral cortical walls occasionally yellow pigmented, external free cortical cell wall continuously thickened, radial longitudinal cortical walls thin or slightly thickened, inner tangential walls continuously thickened; medulla cell walls faintly yellow-pigmented, with small triangular trigones, walls between trigones lacking thickenings; cortical cells on dorsal stem surface arranged in straight longitudinal rows on young and mature shoot sectors. Leaf insertion variable within single individuals, reaching the dorsal stem mid-line or not, leaving zero to three dorsal cortical cell rows leaf-free, dorsal leaf-free strip usually present; leaf insertion not attaining the ventral stem mid-line, leaving two to five ventral cortical cell rows leaf-free. Leaf lobes rotund-ovate, 600–845 µm long by 400–655 μm wide, contiguous, not to weakly falcate, acroscopic base not sharply deflexed away from stem, plane, not interlocking over the dorsal stem surface, stem visible between leaf lobes in dorsal view; margins irregularly but minutely repand, otherwise entire, the interior lobe margin shallowly ampliate, not or only just reaching the opposite stem margin, antical margin curved, exterior margin sharply curved through nearly 100°, postical margin shallowly curved or straight; angle between postical lobe margin and keel c. 135°. Lobules quadrate to rhombic when small and large, one eighth to one sixth the lobe area, 310–475 µm long by 215–420 μm wide; keel curved in small stature lobules, to straight, to arched in large stature lobules, angle between keel and stem 135°, keel turning through 90° mostly at keel-lobe junction, keel apex and postical lobe margin with shallow notch; interior lobule margin free for one third its length, free portion weakly ampliate small stature lobules to moderately ampliate on large stature lobules, extending at most half way across the ventral stem surface; acroscopic margin S-shaped (typical in situ) to straight (when flattened), apical portion inclined toward stem; apex obtuse to acute; free exterior margin straight to curved, occasionally with a small knee above the lobe-lobule junction; margins plane, entire or shallowly repand; lobe-lobule junction slightly antical to, or level with, the acroscopic end of stem insertion; attached to stem along 0.66 of the interior margin, stem insertion more or less linear, gently curved at acroscopic and basiscopic ends, not revolute; lobule apex bearing a single papilla, with another two papilla situated on the interior lobule margin above the stem insertion. Leaf lobe cells rounded-oblong, not arranged in rows, unequally sized, 10–23 µm long by 11–19 μm wide; thin walled with small triangular trigones, medial wall thickenings absent; cells of lobe margin smaller than those of middle, quadrate to rectangular, 9–15 µm long and wide, interior and exterior cell walls not differential thickened, cell lumen not bulging medially, leaf lobe cell surface unornamented, smooth. Oil-bodies not known. Asexual reproduction absent. Dioicous. Androecia on lateral branches that usually terminate following production of 2–4 pairs of antheridial bracts, occasionally these branches continue vegetative growth; bract lobules epistatic, keel deeply curved, bucket-like, free apical portion triangular, apex obtuse, inner margin ampliate, plane; lobes rounded, not caducous; antheridia 1–2 per bract. Gynoecia terminal on leading shoots, subtended by two subfloral innovations, usually full-sized and again fertile; archegonia 130–155 µm tall, archegonia neck six cell columns, 6–8 per gynoecium, on a small disc of tissue, interspersed with paraphyses of 1–3 moniliform cells capped by a hyaline papilla, not encompassed by a protoperianth. Female bracts in one pair, symmetrical, tightly imbricate, elliptic-obovate, weakly falcate, lobe 725–845 μm long by 390-610 μm wide, margins entire; lobules rectangular, one half the lobe area, apex obtuse to broadly acute, keel arched, margins entire; bract insertion lines interlocking dorsally and ventrally, insertion equitant. Perianths 2670–3650 µm long and 630–930 µm wide at mouth, mouth repand, more or less parallel sided for upper third, then tapering to tubular stem perigynium comprising the lower third to half, faint bulb in basal third, broadest c. one third from mouth where 660–950 µm wide, walls bi- or tri-stratose at junction with perigynium, unistratose above, cell walls with triangular trigones. Long stem perigynium present, 5-6 stratose throughout, cell walls not thickened or brown-pigmented, hyaline, perianth-calyptra junction elevated above female bracts on 9–15 tiers of cells. Calyptral perigynium present, 2–4 stratose at base, unistratose above, unfertilised archegonia elevated on surface of calyptra.

Radula buccinifera is endemic to Australia, where it is widespread throughout Tasmania, and Victoria but more restricted in New South Wales, being confined to the eastern side of the Great Dividing Range and associated escarpments. In Western Australia it is confined to the far south-west. The northern limit of this species has not been identified, currently the northernmost locality is Point Lookout in New England National Park, in association with Nothofagus moorei. Cool temperate rainforests dominated by Nothofagus also occur in south-east Queensland and Radula buccinifera may be be found in these areas. Casual field observation suggests the elevational range occupied by Radula buccinifera is correlated with latitude. In Tasmania and Victoria Radula buccinifera occurs across a broad elevational range from sea level to 1500 m,encompassing a range of habitat types from lowland to montane forests, including wet sclerophyll forest and cool temperate rainforest, wetlands, and in alpine scrub and within habitats may occupy a range of microsites from twigs, branches, tree trunks and tree bases, exposed tree roots on the forest floor, to rotting logs, exposed soil on forest banks, dripping rocks adjacent waterfalls, and on rocks within stream beds, sometimes under running water. The ecological range decreases with latitude; the further north, the more restricted to foothills, escarpments, and mountains in association with cool temperate rainforests. This altitudinal contraction is associated with restriction in the diversity of microhabitats occupied, such that at the northern end of its range, where Radula buccinifera occurs at 1000 m or higher, and is always encountered as a lithophyte most frequently on vertical rock faces associated with bluffs and outcrops. Radula buccinifera is one of three [Radula novae-hollandiae, Radula strangulata, Radula buccinifera] Radula species in south-eastern Australia that may be found growing under running water. On rocks it frequently co-occurs with Radula novae-hollandiae, forming mixed mats. The type specimen of Radula novae-hollandiae comprises such a mixed patch. In north-eastern New South Wales it may co-occur and form mixtures with a number of other Radula species, initially presenting as confusing and exceptionally variable individuals.

Radula buccinifera là một loài rêu tản trong họ Radulaceae. Loài này được (Hook. f. & Taylor) Gottsche, Lindenb. & Nees miêu tả khoa học lần đầu tiên năm 1845.