Flora of New Zealand Series

Cephaloziella densifolia R.M.Schust., Nova Hedwigia 22: 199. f. 19. 1972 (1971). 

Holotype: New Zealand, Stewart Is., summit of Tin Ra., ca. 1200 ft., Schuster 53011a.

Evidently autoecious. Androecia intercalary on main stems, compactly spicate; bracts closely imbricate, moderately ventricose at base, with entire margins, the lobes broad. Gynoecia on long branches or ± abbreviated ventral branches; bracts closely sheathing except for lobe apices, connate with each other, like leaves except somewhat larger, with subentire to weakly crenulate-serrulate margins, the lobes triangular, acute, with inner margins and sinuses recurved (as on uppermost leaves); bracteole conspicuously connate. Perianth decolorate throughout, sharply 4–5-plicate for at least two thirds its length, slenderly oblong-obclavate, unistratose to base, the mouth moderately contracted; mouth shallowly plurilobulate and setulose-ciliolate with long, 1–2-celled teeth, the terminal cells tapered, 28–36 × 7–9 µm, the lower flanks of mouth crenulate by free ends of cells.

Sporophyte unknown.

Plants compact, slenderly julaceous-clavate, green, the leaf lobes occasionally to frequently fuscous-tinged, the plants vigorous, the shoots 300–350 µm wide. Branching common, the branches intercalary, ventral and, occasionally, lateral; stolons occasional, long, leafless, originating from ventral surface of base of ventral leafy branches. Stems green, firm, the cortical cells thick-walled and guttulate, the lumina elliptical, the stems ± papillose in surface view. Leaves stiff in appearance, vertical, with base stiffly, obliquely spreading and with lobes suberect to erect, unusually densely imbricate, rarely contiguous, obtusely folded toward each other, transverse, subquadrate, 220–280 µm wide × 220–245 µm long, deeply bifid, to 0.7–0.8; lobes with margins often narrowly recurved (the lobes then characteristically abaxially concave and the leaf somewhat fluted in appearance), the lobes slightly unequal (the ventral larger), narrowly ovate-triangular to broadly lanceolate, sharp, usually 10–12 cells wide at base; keel very short; leaf margins consistently entire, even on subgynoecial leaves; sinus acute, the sinus base often recurved; abaxial face of leaf consistently without cellular projections. Cells tending to become guttulate, with thick walls, the middle lamella distinct, the cells at lobe bases ca. 9.5–11.5 µm wide × 12–16(17–19) µm long; surface with strong, close papillae. Oil-bodies (Schuster, 1972a) 2–3(4) per cell, colorless, subhomogeneous to faintly papillose-botryoidal, smooth and glistening, small, 3–3.3 µm in diam. and spherical, to ovoid and 2.8–3 × 3.5–4 µm, a few to 3.5–4.4 × 4–4.5 µm; oil-bodies often largely lacking in mature leaves; chloroplasts subequal to oil-bodies in size. Underleaves lacking (even on the most vigorous plants) or sporadically present as 1-celled spurs. Gemmae lacking.

Comments : Plants of this species differ from typical members of the genus in being much denser-leaved and more vigorous. Diagnostic are the rigid leaves with suberect to erect lobes, with the leaf loosely folded along the midline and delimiting only a very short keel. In fact, plants have the superficial aspect of a minute Gymnomitrion cuspidatum or of a small, green Anthelia (Schuster, 1972a). Distinctive also are the deeply bifid (to 0.7–0.8) leaves, which often have narrowly recurved lobe margins often lending the lobes characteristically abaxially concave. The leaf surface has strong close papillae. The perianth is unique among Austral members of Cephaloziella in the shallowly plurilobulate and setulose-ciliolate mouth, with long 1–2-celled teeth with the terminal cell tapered.

The species has been subdivided into two varieties, as follows.