Flora of New Zealand Series

Pseudocephalozia R.M.Schust., Nova Hedwigia 10: 21. 1965.

Type: Pseudocephalozia paludicola R.M.Schust.

Plants often fleshy, soft, pellucid whitish green to pale brown, medium-sized, the leafy shoots to 2.7 mm wide. Plants usually with a system of basal, creeping to geotropic, small-leaved, microphyllous, strongly elongated, often copiously branched stoloniform axes from which arise ascending to erect leafy shoots that are simple or once-branched. Branching nearly exclusively ventral- and lateral-intercalary, rarely of Frullania and/or Microlepidozia type, the lower parts of leafy branches small-leaved. Stems with a distinct hyaloderm (at times ill-defined on erect leafy axes), the cortical cells thin-walled or with the exterior wall thickened, in up to 12 rows in ours (to 31 in extraterritorial species); medullary cells thin-walled. Rhizoids at bases of leaves and underleaves on stoloniform axes, restricted to underleaf bases on leafy axes, the tips sometimes swollen and “mycorrhizal.” Leaves unistratose (in ours) or 2–5-stratose in median to basal sectors ( subg. Lobulatae (R.M.Schust) R.M.Schust., South America), transversely to clearly succubous in insertion and orientation, the insertion extending to stem midline dorsally; leaves mostly obtrapezoidal, weakly to deeply concave to cucullate, 3–4(6)-dentate to -lobulate to 0.4–0.65 or less; lobes generally sharply acute to acuminate, the margins entire; disc usually 7–8 or more cells high. Cells thin-walled, trigones minute to small or lacking; surface smooth or slightly roughened or striolate. Oil-bodies colorless, large and conspicuous, botryoidal, (1)2–6 per cell. Underleaves variable, some large, (2)3–4-lobed, wider than stem and with a conspicuous disc, others small and scale-like, with 2–4 reduced, 1–few-celled lobes and with a vestigial disc 1–few cells high. Asexual reproduction lacking.

Plants dioecious. Androecia subspicate, becoming intercalary on short or long ventral-intercalary branches or (at times in Pseudocephalozia cucullata) intercalary on main shoot; bracts deeply concave to subnaviculariform, the apices 2–3-dentate to -lobate; antheridia 1–2 per bract, the stalk 1- or 2-seriate; bracteolar antheridia occasional, the androecia then isophyllous. Gynoecia on abbreviated to rather short lateral- or ventral-intercalary branches; bracts of innermost series 2–4-stratose toward base or unistratose throughout, the apices 2–4-lobulate or -lobate, the lamina margins entire or with a few slime papillae and/or a few small teeth, rarely with a lobe; bracteoles similar or identical to bracts. Perianth terete below and feebly to distinctly bluntly trigonous above, at times obscurely 5-plicate distally, or (P. lobulata) 4– 5-plicate throughout; perianth contracted toward the mouth, the mouth lobulate, the lobe apices either crenulate-denticulate by short (P. lobulata) or more often elongate cells that are laterally free for varying distances, or the lobes terminating in a single elongated cell or 2 laterally juxtaposed elongated cells; perianth polystratose toward base, unistratose above. Calyptra extending ca. 0.75 perianth length.

Seta with 8–20 rows of large outer cells and 10–23 rows of small internal cells. Capsule ellipsoidal, the wall 3(sporadically very locally 2)-stratose (in ours) or 3–4-stratose; outer layer of cells with two-phase development, the longitudinal walls with continuous sheets of secondary wall material, often extended as nodules, alternating with primary walls devoid of thickenings; inner cells with a few and weak, often incomplete, semiannular bands.

Spores vermiculate, at times irregularly areolate. Elaters rather rigid, at most feebly tortuous, bispiral.

A genus of six species. Three are Australasian ( subg. Pseudocephalozia), of which two occur in New Zealand, and one (Pseudocephalozia leptodictyon R.M.Schust.) is known from alpine New Guinea. The other three species ( subg. Lobulatae) occur in southern South America: one (P. quadriloba (Steph.) R.M.Schust.) has an Andean distribution (see Engel, 1978) and extends north at higher elevations (3200–3600 m) in the Andes to Venezuela and disjunct in Costa Rica (at Volván Poás, 2600 m); also on Inaccessible Island; a second species is known from a few collections in the southern sector of the Magellanian zone (P. cucullata J.J.Engel & R.M.Schust.) and a third is known only from the type in the Valdivian zone (P. lobulata (Herzog) R.M.Schust.).

The two subgenera are sharply divided:  subg. Pseudocephalozia (our area) has unistratose leaves, underleaves and gynoecial bracts; uniseriate antheridial stalks; and a bistratose capsule wall. Members of subg. Lobulatae have multistratose leaves, underleaves and gynoecial bracts; biseriate antheridial stalks; and a 3–4-stratose capsule wall.

References: Schuster and Engel (1974; mon.); Schuster (2000a).