Lepidozia novae-zelandiae Steph.
Plants brittle, prostrate, in loosely interwoven, ± pure mats, the shoots slender, delicately spinescent, stiff and wire-like, with widely spreading branches, green, nitid when dry, the shoots minute. Branching exclusively of Frullania type, ± distantly 1-pinnate, the branches often becoming whip-like, flagelliform and microphyllous; secondary branches sporadic; branch half-leaf subsymmetrical, cordate at the base, 2-lobed to ca. 0.4; first branch underleaf (1)2–3(4)-lobed, inserted on ventral side of branch base to the ventral-lateral side of junction of main axis and branch, nearly aligned with underleaves of branch. Ventral-intercalary branching not seen. Leaves when moist (or dry) moderately concave, with the lobes somewhat incurved, contiguous to ± distant, with much of stem visible in dorsal view, somewhat longer than wide, 0.25–0.3 mm long at longest point, 0.25–0.35 mm wide at widest point, spreading, the insertion subtransverse to weakly incubous; leaves variable, ± symmetric to moderately asymmetric, subequally 4(5)-lobed, the leaves divided to ca. 0.6 (median sinus), in ± symmetrical leaves the distance from dorsal sinus base to insertion not much greater than that from ventral sinus to insertion. Lobes long-acute to short-acuminate, typically somewhat apiculate, the ventral shorter than the dorsal lobes and somewhat divergent, the dorsal lobes 4–5 cells wide at base; lobes terminating in a single cell or in a uniseriate row of 2 cells, the cells of uniseriate row elongated (to 2:1), typically strongly thick-walled, the septa somewhat to distinctly dilated, the terminal cell tapering to a point; surface of lobes coarsely papillose. Disc subsymmetric to obliquely truncate, 6–10 cells high at dorsal sinus, 4–6 cells high at ventral sinus, the margins entire, the dorsal margin ± straight, abruptly cordate near the base, entire to sinuate; ventral margin entire or sinuate, sometimes with an accessory lobe. Cells of disc-middle often strongly thick-walled, occasionally with small to medium trigones, 11–16 µm wide × 14–22 µm long; median basal cells in 1 (locally 2) rows of enlarged cells; marginal cells of disc and lobes with a strongly thickened, often concave outer wall (the wall thickening often crescentic and bulging into the cell lumen), the septa ± dilated; surface of disc finely to distinctly striate-papillose. Underleaves inserted on 4–6 rows of stem cells, spreading, symmetrically 4-fid to ca. 0.5 (median sinus), narrowing to the insertion, the lobes plane, slenderly acuminate, terminating in a single cell or in a uniseriate row of 2–4(5) cells; disc 4–7 cells high at median sinus, the margins plane, entire.
Androecia and gynoecia not seen.
Key to the varieties of L. novae-zelandiae
Comments : Lepidozia novae-zelandiae is closely allied to L. laevifolia, as evidenced by the coarsely papillose leaves (Fig. 40: 6) and by the sinuate leaf margins. It differs in the subtransverse to weakly incubous leaf insertion (Fig. 40: 2), the ± straight dorsal margin (Fig. 40: 2–4), the strongly thickened outer walls and dilated septa of the marginal cells of both disc and lobes (Fig. 40: 5–9), the elongated (to 2:1) cells of the uniseriate portion of the lobe apices (Fig. 40: 5–8), and the distinctly thickened stem epidermal cell walls (Fig. 40: 14, 15). Lepidozia pumila resembles this species in the ± straight dorsal margin of the leaves and thickened walls of the marginal cells, but the leaf surfaces are typically smooth, and the leaves are more distinctly incubous.
In Lepidozia novae-zelandiae the abaxial cell walls of disc and lobes are typically thickened; these thickenings can also be seen by focusing on the ventral margins of the lobes. Similarly thickened cell walls are present in L. fugax (Fig. 39: 4, 9), but the characteristic deciduous lobe tips, and the barrel-shaped cells and constricted septa of the uniseriate row, will immediately distinguish that species from L. novae-zelandiae.
Three extremes are assigned to this species, which differ as follows.
