Cephaloziella muelleriana R.M.Schust.
Cephaloziella muelleriana R.M.Schust., Nova Hedwigia 63: 24. f. 3, 4. 1996.
Holotype: New Zealand, North Is., along Whirinaki River, Schuster 95-371.
Plants in interwoven small, gregarious patches, or solitary amidst small acrocarpous mosses, minute, with sterile shoots 300–335 µm broad. Branching irregular, the branches ventral-intercalary and at least sporadically, lateral-intercalary; terminal branches unknown. Stems relatively flimsy, 5–6 cells in diam. on weak shoots, 7–8 on vigorous shoots, the cortical cells in an ill-defined, non-pigmented, only weakly to moderately thick-walled layer, in surface view conspicuously striolate; medullary cells feebly firm-walled, with rounded angles, the peripheral stratum at times smaller. Rhizoids scattered, rather frequent even to gynoecial region. Leaves obliquely spreading, remote, transverse, vigorous ones usually loosely folded, evident chiefly at sinus bases, the leaves when flattened narrowly obtrapezoidal in outline, 235– 245 µm wide × 180–200 µm long to 260–265 µm wide above × 225–260 µm long, bilobed to 0.5–0.6; lobes narrowly triangular, (7)8–9(10) cells broad at base, entire-margined, ending in 1 or 2 single cells that are not elongated but on vigorous, sterile shoots often somewhat incurved at the tips; sinus rectangular to obtuse-angular on flattened leaves, often rounded at base, on vigorous leaves sometimes somewhat recurved or gibbous and sometimes obscurely armed with a blunt projection just proximal to sinus bases; abaxial surface of lower parts of leaves sometimes obscurely mamillose. Cells rather variable, firm-walled and with rounded angles, the lumina often rounded, at lobe bases 14–18 µm wide × 16–19 µm long; surface conspicuously, rather closely papillose distally, becoming striolate basally. Underleaves distinct on sterile shoots, somewhat spreading, ovate-lanceolate to sporadically bidentate or bifid. Gemmae lacking.
Dioecious. Androecia on long, leafy axes, becoming intercalary, sometimes the apical innovation again androecial after developing only 2–3 gyres of leaves, the androecia compactly and rather smoothly spicate; bracts in 5–7 pairs, closely imbricate, concave, the lobes erect, narrowly triangular, serrulate, sharp-pointed. Gynoecia usually on intercalary branches of limited length, often developing only (1)2–3 gyres of leaves and underleaves prior to initiation of bracts; bracts in 2–3 gradually larger series, the innermost and those of penultimate series bifid to 0.35, the sharp, triangular lobes regularly and sharply serrulate with strongly projecting, thick-walled upper ends of marginal cells; lobe apices mostly abruptly hooked, the hook usually formed of a single, long-acute, thick-walled, tapered, terminal cell; bracts of innermost series 2(3)-lobed to 0.25–0.35, the acute to subacuminate lobes strongly serrulate, the lobes and margins usually broadly decolorate, hyaline, the cells of lobes formed of very strongly thick-walled and elongated cells; bracteole broadly connate with bracts on both sides, narrower and somewhat shorter than bracts, bilobed to 0.25, the lobes like those of bracts. Perianth 470–525 µm diam. × 850–925 µm long, up to 540 µm diam. × 1650–1900 µm long, slenderly ovoid-ellipsoidal, deeply 3–4-plicate in distal third, narrowed in the distal 0.25–0.35 into a rather narrow mouth; mouth decolorate and bleached, formed of exceedingly thick-walled and strongly elongated cells in the distal 0.1–0.2, below of brownish pigmented, chlorophyllose short-oblong cells; mouth fringed with linear cells (6.5–9:1), 9–11 µm wide × 52–72 µm long, free at the very apices and projecting as thick-walled crenulations; perianth unistratose virtually to base, but at the very base becoming a little fleshy and (2)3-stratose.
Seta formed of 4 rows of inflated, very large outer cells and 4 rows of minute internal cells. Capsule ellipsoidal, purplish brown, with a basal “shoulder” formed of inflated cells in a single tier, the walls 2-layered; outer layer of cells mostly oblong, the longitudinal walls with conspicuous radial nodular thickenings, often opposed, not or scarcely ever confluent; base of each valve with a “cushion” of 8–9 cells, arranged in a fan-like pattern, narrowed basally, broadened distally, 70–80 µm long, the radial walls with remote, minute, radial nodular thickenings; inner layer of cells more variable in size, shape, and thickening patterns, with very small, well-separated, radial nodular thickenings, the thickenings not extended onto tangential walls on some cells, feebly extended on others, on many as an incomplete to complete narrow band, the thickenings then semiannular.
Spores 10.5–12 µm in diam., purplish brown, delicately verruculose. Elaters hardly tapered or tortuous, 7–7.5 µm diam., 2-spiral, the spirals well defined, 2.2–2.4 µm wide.
Distribution and Ecology : Endemic to New Zealand: North Island (380 m).
Known, to date, only from the type collection, on exposed mineral soil of an exposed sandy-gritty bank, and growing amidst small acrocarpous mosses, mixed with Cephaloziella subspinosa.
Comments : Cephaloziella muelleriana may be distinguished from C. byssacea, another dioecious species, by a number of features, among them the ♀ bract lobes and often also the subgynoecial bracts are notably sharply and closely serrulate by thick-walled projections of the walls of the marginal cells, and the strikingly elongated perianth-mouth cells with walls so markedly and massively thickened that the lumina is nearly obliterated and often vestigial. The highly differentiated cells at the perianth mouth are unique in the genus.
