Bazzania monilinervis (Lehm. & Lindenb.) Trevis.
Jungermannia monilinervis Lehm. & Lindenb. in Lehm., Nov. Min. Cogn. Stirp. Pug. 4: 56. 1832.
Mastigobryum monilinerve (Lehm. & Lindenb.) Nees in Gottsche, Lindenb. & Nees, Syn. Hepat. 223. 1845.
Type: Australia.
[Fig. 102; Fig. 104: 4, oil-bodies, p. 452]
Plants prostrate, yellow-green to pale olive-green; plants when dry distinctly nitid and with leaves membranous; shoots small, to 2.5 mm wide. Branching rather frequently pseudo-dichotomously furcate, the branches of Frullania type; branch half-leaf ± symmetric, ovate, undivided, nonvittate, tapering to a sharp apex; first branch underleaf 2–3-lobed, inserted on ventral-lateral side of stem below the branch, free. Ventral-intercalary branches occasional, leafy; stoloniform branches sporadically present. Stem cortical cells with thick longitudinal walls, the transverse walls ± thin. Rhizoids from basal cells of underleaves of main shoots. Leaves rigid, alternate, horizontal, imbricate, covering some or most of stem in dorsal aspect, widely spreading (ca. 90°), plane to slightly convex (strongly convex when dry), the apex often slightly deflexed; leaves vittate, 420–565 µm wide × 730–1120 µm long, the insertion narrow and strongly incubous, the leaves asymmetrically narrowly ovate; apex transverse to moderately oblique, symmetrically and rather deeply 3-dentate, the teeth widely divergent, spinulose, 3–4(5) cells wide at base, narrowly acuminate, terminating in a uniseriate row of 4–11 irregularly thick-walled cells, the terminal cell tapering to a rounded tip, the apex otherwise entire; dorsal margin strongly ampliate, extending to middle of stem to across and slightly beyond the stem, cordate to subauriculate at base, entire; ventral margin nearly straight, entire. Vittae of leaves sharply defined, running parallel to and 5–6 cells within the ventral margin and broadening in the apex, the vitta 3–4 cells wide; cells of vitta 25–31 µm wide × 26–39 µm long, very thin-walled, with distinctly knot-like trigones; cells outside the vitta much smaller, 11–18 µm wide and long, ± evenly thick-walled; surface smooth to indistinctly papillose. Oil-bodies present in all leaf cells except cells of the uniseriate row which have only chloroplasts, the cell lumen of both non-vitta and vitta cells packed with oil-bodies and chloroplasts, the oil-bodies in vitta cells nearly filling the lumen, 2–6 (up to 9, perhaps the result of oil-bodies breaking up) per cell, homogeneous, broadly elliptic to ovate, (8.8)10.7–13.7 × 18.5–21.5 µm, the surface appearing lumpy, distorted and potato-like, occasionally having a pinch-like depression, with very irregular internal differentiation of huge oil masses which give an irregularly cloudy appearance to the oil-body. Oil-bodies in nonvittate cells hyaline, 2(3) per cell, essentially smooth but with faint, irregular, internal oil-droplets, the oil-bodies 2.9–3.9 × 6.8–7.8 µm. Chloroplasts large for cell size. Underleaves conspicuous, ca. 2.5× stem width, membranous, free, appressed to the stem, contiguous to feebly imbricate, slightly convex (ventral view), wide elliptic to wide ovate or ± orbicular, the apex very shallowly divided into 4 small irregular teeth or almost imperceptibly 4-dentate, in either case the teeth terminating in an elongated slime papilla, or the apex truncate and entire except for 4 closely juxtaposed slime papillae; distal ca. 0.5–0.8 of underleaf colorless, the cells ± isodiametric, thin- to slightly and evenly thick-walled; cells in the basal sector thick-walled and densely chlorophyllose, sporadically giving rise to abundant rhizoids; margins entire; surface smooth.
Androecia and gynoecia not seen.
Distribution and Ecology : New Zealand: Stewart Island (10–530 m), South Island (520–850 m), North Island (835–1340 m); Australia: Tasmania (where apparently common), Victoria, New South Wales. Miller et al. (1983) report the species for Tahiti; the record requires confirmation. In New Zealand known from Fiordland, Westland (Whataroa), Western Nelson, Southern North Island (Tararua Ra.), Gisborne (Raukumara Ra.) and Auckland (Coromandel Peninsula) EPs.
The species has a sporadic distribution in New Zealand. On Stewart Island the species occurs between 10 and 340 m within the forest zone and forms loose, often pendent, at times large mats in damp, deeply shaded, protected niches such as in crevices or on ledges beneath overhangs of rocky outcrops, or under partial cover of logs, or at the base of tree trunks. In the South Island known from Westland Natl. Park (Gillespies Beach Road, between Tornado and Whelan creeks) occurring on tree bark with Acromastigum mooreanum in a wet forest. On Mt. Turiwhate (central Westland, 850 m) in a root cave under Metrosideros umbellata in upper montane Weinmannia racemosa – Metrosideros umbellata forest. In the North Island known from Coromandel Forest Park (835 m, summit of Table Mtn.) in a wet mossy forest of Lepidothamnus intermedius, Ixerba brexioides and Dacrydium cupressinum with occasional Phyllocladus glaucus. At this site it occurred on a bryophyte-covered stump with Acromastigum anisostomum and A. marginatum as well as in loose, soft, pendent masses in deeply shaded niches such as from the ventral-lateral side of a shaded bryophyte-covered log. Also on Mt. Te Aroha (880–890 m) forming loosely pendent tufts in deeply shaded, protected niches on banks within a forest dominated by stunted Nothofagus menziesii, associated with Dracophyllum and Quintinia serrata. Also on the Maungawaru Plateau (Raukumara Ra., ca. 1310 m, Druce s.n. [MPN]) where corticolous and with Bazzania nova and Leucobryum candidum. In the Marino Mtns. it occurred on the roof of a cave formed by a sandstone boulder under Nothofagus menziesii forest in a site affected by cold, moist air drainage. This is the only New Zealand species of Bazzania known to be epiphyllous—on tree ferns (Cyathea) with Radula pseudoscripta and Heteroscyphus sp. on Stewart Island (Tin Ra., West Hut, Martin 593 [MPN]; Port Pegasus, Martin 610, 623 [MPN]). Other accompanying species are Balantiopsis diplophylla, Categonium nitens, Hymenophyllum flabellatum, H. revolutum, Lepidozia spinosissima, Mittenia plumula, Plagiochila fasciculata, Psiloclada clandestina, Rhizogonium pennatum, Telaranea elegans and Tylimanthus diversifolius.
Comments : Readily distinguished by the vittate leaves, the widely divergent spinulose teeth of the leaf apices and the large orbicular underleaves, which are shallowly lobulate or divided into 4 minute teeth terminating in an elongate slime papilla (Fig. 102: 7–9) which is sometimes the only indication of the lobulate nature of the underleaf. The leaves are strongly convex and distinctly membranous (like onion skin in appearance) when dry. The narrowly acuminate teeth of the leaf apex are unique among New Zealand Bazzania species and consist almost entirely of a uniseriate row of up to 11 cells (Fig. 102: 6). Useful field characters that will distinguish the species are the highly nitid texture of the plants, the membranous, vittate leaves and the divergent, acuminate lobes. This species is the only one of our species known to be epiphyllous.
