Liverworts v1 (2008) - A Flora of the Liverworts and Hornworts of New Zealand Volume 1
Copy a link to this page Cite this record

Cephaloziella invisa R.M.Schust.

Cephaloziella invisa R.M.Schust.

Cephaloziella invisa R.M.Schust., Nova Hedwigia 63: 30. f. 5, 6. 1996. 

Holotype: New Zealand, North Is., Otupaka Frost Flats on South Road, SSW of Minginui, Schuster 95-386.

Plants very slender, pale brownish, with tips of actively growing shoots very locally with a little deep purplish pigmentation, minute, the sterile leafy shoots only 240–330 µm wide. Branching rather sparing and irregular, the branches (apparently) all ventral-intercalary, soon acquiring the vigor of the parent shoot. Stems wiry, somewhat brittle, very slender, pale brownish with age, relatively pellucid, the cortex of sterile shoots in 1 layer of only ca. 16 cell rows of subisodiametric cells, in surface view mostly subquadrate; medulla of only 11–14 rows, the walls as thick as those of cortical cells or almost so. Rhizoids scattered, long, frequent. Leaves on sterile shoots erect-spreading to moderately widely spreading, always exceedingly remote, transversely oriented but insertion lines feebly succubous, mostly moderately concave but never folded, the lobe apices usually incurved, in situ sometimes weakly connivent, the leaves (on sterile shoots when flattened) narrowly obtrapezoidal, 135–165(175) µm wide × 125–135(145) µm long, bifid to 0.4–0.5; lobes triangular, acute, 4–5 cells wide on sterile leaves (only sporadic leaves with lobes 6 cells wide), ending in a single cell or sporadically to commonly in a uniseriate row of 2 cells, the terminal cells not elongated or sporadically elongated and incurved but not otherwise differentiated; disc 4–5 cells high from sinus base to leaf base, with margins entire but isolated leaves with 1(2) weak lateral teeth formed by projecting ends of marginal cells. Cells firm-walled but with lumina ± angular, at lobe base 11–14 µm wide × 17–19 µm long, rather irregular in shape, the cells within the lobes mostly quadrate, the cells at leaf base appreciably larger. Oil-bodies (Schuster, 1996a) smooth to very obscurely granular, subhomogeneous (no evident internal structure), 3–6 per cell, tiny, much smaller than chloroplasts, 1–1.6 × 1.2–1.75 µm. Underleaves present throughout, usually lanceolate, suberect from a spreading base and often with apex incurved, less than 0.25× the leaf length, usually only 3–4(6) cells broad at base, the apices sometimes bidentate with strongly elongated cells forming the lobes. Asexual reproduction absent.

Dioecious (?sometimes pseudodioecious). ♂ and ♀ Gametangia on ± elongated, unspecialized axes. Androecia soon becoming intercalary, brownish, at times with faint reddish pigmentation, usually exceedingly compact, only 230–250(300) µm broad and developed on weak and very slender shoots, usually only (160)200–250 µm broad, with exceedingly remote leaves; bracts in 3–5 pairs, very closely imbricate, mutually ensheathing, concave, only moderately ventricose, equally bifid, the lobes triangular, often strongly incurved, often ending in a uniseriate row of 2 elongated cells, the lobe margins entire to, at most, with 1(2) obscure teeth. Gynoecia, if unfertilized, always innovating, the innovations again soon fertile, the gynoecia on elongated shoots that are more vigorous than the ♂ shoots (to 350–385 µm wide), with leaves less remote and lobes sometimes 6–7 cells wide, the apices acute, often strongly incurved. ♀ Bracts (unfertilized gynoecia) connate with one another, the bracteole connate on one side for 0.25–0.35 and more shallowly so on the other side, the bracts and bracteole forming an erect sheath clearly investing the perianth; bracts broadly quadrate or rounded-quadrate, the bracteole oblong to oblong-ovate, ca. 270 µm wide × 400 µm long, usually bifid to 0.3–0.4 bifid, the lobes of bracts and bracteole irregularly denticulate. Perianth mouth of hyaline cells in 2–3 tiers, strongly elongated, the terminal cells 7–10 µm wide basally × 38–54 µm long (4.5–6[8]:1), thick-walled, especially at the tapered and free tips, but lumina distinct; cells below the hyaline apex becoming oblong to oblong-quadrate, less thick-walled.

Sporophyte unknown.

Distribution and Ecology : Endemic to New Zealand: North Island (700 m).

Known from two collections from the type locality. The Otupaka “Frost Flats” is an open, low-lying area with rather dense scrub of Leptospermum scoparium and Dracophyllum subulatum with abundant Cladonia, and is a rigorous habitat for liverworts. At this site desiccation occurs regularly, and plants are subjected to strong frosts and hardly shaded by the low (0.5–1 m tall) shrubs of L. scoparium and Dracophyllum. Lophozia pumicicola also occurred at the site.

Comments : Cephaloziella invisa is distinct in having rather shallowly bilobed, entire- margined leaves, which when flattened have a rounded and wide sinus, which is unusual for the genus. The disc is usually only 4–5 cells high from leaf base to the sinus base. The leaf lobes are usually 4–5 cells wide at the base and terminate in a triangular cell or a uniseriate row of 2 subisodiametric cells. Plants are dioecious, with ♂ and ♀ gametangia on long, unspecialized axes, do not produce gemmae and are green (but brown in lower, buried sectors), but may develop very local deep purplish pigmentation. The androecia are often distinctly compact and the bracts have entire lobes. The ♀ bract lobes are long-acute to subacuminate and characteristically hooked at the attenuated tip, and the perianth mouth has notably elongated cells, often 4–6:1 or longer.

Click to go back to the top of the page
Top