Zoopsidella caledonica (Steph.) R.M.Schust.
Zoopsis caledonica Steph., Sp. Hepat. 6: 318. 1922. Zoopsidella caledonica (Steph.) R.M.Schust., Taxon 18: 57, 87. 1969.
Type: New Caledonia, Lerat.
Zoopsis foliosa Herzog & E.A.Hodgs. in Zotov et al., Trans. Roy. Soc. New Zealand 68: 320. 1938, nom. nud. (cf. Schuster, 1963b, p. 274, 1999, p. 114; Scott, 1969, p. 169).
[Plate 8E, F; Fig. 113: 1, oil-bodies, p. 504]
Plants loosely prostrate, light to whitish green, distinctly nitid when dry, medium, to 1.3 µm, flat. Branching irregular, sparing, the branches mostly ventral-intercalary; Frullania - and Zoopsis -type branches much less frequent, from both right- and left-hand sides of axis; stoloniform branches common. Stem with cortex in 6 rows of somewhat inflated, leptodermous cells, the 2 dorsal rows very large, the ventral 2 rows of cells notably smaller; medullary cells very small, in 7–13 rows. Leaves contiguous, with at most 1 cortical cell intervening between successive leaves on each side of axis; leaves flat, regularly widely spreading, nearly longitudinally inserted, leaving a broad strip of 2 cell rows leaf-free, rectangular-lingulate, for the most part nearly parallel-sided, but weakly tapering toward the apices, 180–280 µm wide × 450–700 µm long, symmetrically bilobed to 0.2–0.25; lobes (2)3–4-celled, typically ending in a short uniseriate row of 2 submoniliform, persistent cells, the apical cell of leaf lobes not modified into papillae; disc 4 cells wide throughout, ca. 5–6 cells high. Cells large, the size and shape uniform throughout disc, the median cells of the disc 55–75 µm wide × 75–100 µm long; surface smooth. Oil-bodies occupying significant portion of cell lumen, bunching up in differing parts of the cells, appearing packed in cell, hyaline and somewhat translucent, 8–14 per leaf disc cell, smooth, but obscurely, irregularly and indistinctly segmented, the surface appearing irregularly pinched. Underleaves small, usually of 2 basal cells forming a vestigial disc, and 2 vestigial lobes, each of 1(2) inflated cells, ending in a slime papilla.
Autoecious. Androecia on small, spicate, ventral-intercalary branches, the branches at times crowded and in the axils of several successive underleaves; bracts in 3–6 pairs, weakly pouched at base, bilobed; antheridia 1 per bract, the stalk uniseriate. Gynoecia on weak, ventral-intercalary branches; bracts of innermost series oblong, bifid to 0.5–0.65, the disc only (1.5)2–3 cells high, the lobes lanceolate to acuminate, terminating in a uniseriate row of 2–5 cells, the lobe margins with 1–2 small teeth; bracteole bifid only to 0.35–0.45, otherwise similar to bracts. Perianth mouth deeply 6-lobed, the lobes acuminate to subcaudate, terminating in a uniseriate row of 3–4 strongly elongated cells, the terminal 1–2 cells (4–6:1), the uniseriate row supported by 2–4 laterally juxtaposed cells that are ca. 2:1 or less, the lobes entire, rarely with a tooth.
Seta with 8 rows of outer cells surrounding 4 rows of slightly smaller inner cells. Capsule ellipsoidal, the wall 2-stratose; outer layer of cells somewhat irregular, with two-phase development, the primary walls delimiting mostly subquadrate to short-oblong cells, each divided longitudinally and occasionally transversely, the secondary walls with rather few, confluent, nodular thickenings; inner layer of cells with rather few, weak, incomplete to complete semiannular bands.
Spores 13–15 µm in diam., with very low, furcate-anastomosing ridges imperfectly delimiting areolae. Elaters 7.5–9.5 µm wide, bispiral, the spirals 2.5–3 µm wide.
Distribution and Ecology : New Zealand: Stewart Island (100–530 m), South Island (0– 720 m), North Island (180–540 m), Chatham Islands; New Guinea, New Caledonia, Fiji. In New Zealand known from Westland, Southern North Island (Tararua Ra.), Volcanic Plateau (Atiamuri), Auckland (Waitakere Ra.) and Northland EPs.
Broadly distributed in New Zealand, but local and abundant and common only in the montane forests of Westland. The species occurs over permanently damp peaty soil deep in humid, deeply shaded, protected, cave-like areas under tree masses (especially under Metrosideros umbellata) or deep in shaded pockets in forests usually of Dacrydium cupressinum, Libocedrus bidwillii, Weinmannia racemosa, Metrosideros umbellata and Quintinia serrata. It is associated with Acromastigum colensoanum, Bazzania nitida, B. nova, Kurzia hippuroides, Leucobryum candidum, Mittenia plumula, Psiloclada clandestina, Rhizogonium distichum, R. pennatum, Saccogynidium australe, Tylimanthus diversifolius, Zoopsis argentea var. argentea and Z. ceratophylla. Also on organic substrates such as the fibrous caudices of Dicksonia squarrosa or Cyathea medullaris (with Calomnion complanatum and Marsupidium epiphytum) or deep in recesses of rotted, fallen tree trunks. On Stewart Island (Mt. Rocky Track, 100 m), in a mixed broadleaf–podocarp forest dominated by Weinmannia racemosa, and also including Dacrydium cupressinum, Prumnopitys ferruginea and Metrosideros umbellata where in a shaded, protected hollow formed by tree buttresses. Also, notably at the Mt. Rocky summit area (530 m), deep in a shaded protected niche under tussock in mosaic communities of dense heath-forming shrubs to 3 m tall, penalpine herbs and dwarf heaths to 0.5 m tall, dominated by stunted Leptospermum scoparium and Dracophyllum and a ground tier including Empodisma minus.
Comments : A distinct species that can be confused only with Zoopsis ceratophylla (p. 484), which it resembles in the symmetrical, elongated, bilobed leaves with the lamina formed of 4 cell rows. It differs in the narrowly oblong-lingulate leaves, consistently tapered to the subparallel lobes that terminate in 1–2 cells that are not conspicuously moniliform, with the terminal cell never ending in a slime papilla. On the other hand, the leaves of Z. ceratophylla are narrowly oblong to obovate-cuneate, often widest in the distal half, with lobes that are somewhat spreading and terminate in a uniseriate row of (2)3–4(6) moniliform cells and the terminal cell at times is an unspecialized slime papilla. In Zoopsidella caledonica the cells of the lamina are conspicuously smaller and the oil-bodies are hyaline, smooth and almost homogeneous or only very faintly granular vs. opaque, rough, dull-surfaced and granular-botryoidal in Z. ceratophylla.
Schuster (1999b) erroneously stated that Zoopsidella caledonica is dioecious, but did not mention presence of androecia. The species is autoecious.