Lophozia (Dumort.) Dumort.
Jungermannia excisa Dicks., Fasc. Sec. Pl. Crypt. 11. 1793.
Lophozia excisa (Dicks.) Dumort., Recueil Observ. Jungerm. 17. 1835.
Type: England, Holt and Edgefield heaths, Dickson.
Jungermannia propagulifera Gottsche in Neumayer, Deutsch. Exp. Int. Polarforsch. 2: 451. 1890, syn. fide Schuster (1969c, p. 512, 521).
Lophozia propagulifera (Gottsche) Steph., Exped. Antarct. Belge. Bot. 3, 4. 1901 (Sept.); Sp. Hepat. 2: 139. 1901 (Oct.). Lectotype (fide Grolle, 1972d): South Georgia, Bachground overhalb der Pinguinbay, Will.
Plants variable in size and appearance, fleshy, soft-textured or flaccid, prostrate to suberect, pale to dark green or yellow-green, or tinged, especially above, with bright red, vinaceous-red, purplish red, purple, reddish brown or brown. Stems fleshy, the cortex weakly differentiated, the cells thin-walled, slightly smaller than or subequal to the dorsal medullary cells; medulla differentiated, the cells in dorsal portion larger, leptodermous, colorless, those in ventral portion smaller, with age strongly mycorrhizal and brownish. Rhizoids hyaline, numerous, scattered on ventral surface to shoot apex, long. Branching sparing, the branches of lateral-intercalary type. Leaves soft-textured and rather delicate, often somewhat undulate, spreading, distant to contiguous, succubously oriented, the insertion distinctly succubous, somewhat asymmetrically ovate to broadly ovate-quadrate, when well developed slightly wider than long, typically weakly asymmetrically bilobed to 0.2–0.25 (the dorsal usually slightly smaller), at times divided to 0.35; lobes broadly acute, obtusely apiculate to rather sharply angular, entire; sinus shallow and crescentic; dorsal and ventral margins arched, the ventral margin somewhat more strongly so, particularly above the somewhat dilated ventral base, the margins entire (except near ♂ bracts, then often with a dorsal tooth). Cells thin-walled and with trigones minute to small, median cells 25–30 µm wide × 30–35(40) µm long, the cells of lobe margins 23–28 µm in diam.; surface smooth. Oil-bodies (fide Schuster, 2002a) (10)12–22(24) per cell, granular-botryoidal, spherical to ovoid. Underleaves lacking. Asexual reproduction via gemmae, the gemmae (in ours) typically present, bright red, 1–2-celled, polygonal, thin-walled but often with 1–2 angles acutely drawn out into thick-walled tips; gemmae producing shoots and leaves hardly modified, the leaf margins not becoming erose-lacerate. Fungal partner a basidiomycete.
Paroecious. Androecia with bracts in 2–4(5) pairs, similar to leaves but somewhat larger and more erect, only slightly saccate, with a tooth somewhat above dorsal base; antheridia 1–2(3) per bract, the stalk uniseriate. Gynoecia usually with 1–several subfloral innovations; bracts larger than leaves, somewhat sheathing perianth at base, the margins crispate, slightly to much broader than long, irregularly 3–5-lobed, the lobe margins entire or sporadically with a few small teeth; bracteole much smaller than bracts, often connate on one or both sides for up to 0.5, oblong to lanceolate. Perianth ca. 0.5–0.75 emergent, cylindrical-clavate, strongly plicate in distal 0.3–0.5, contracted to mouth; mouth shallowly lobed, the lobes with marginal cells notably weakly differentiated, crenulate by firm-walled cells that are free only at distal ends + a few cells projecting as blunt, short teeth rounded at the summit.
Capsule ovoid, the wall 3–4-stratose; outer layer of cells with nodular thickenings; inner layer of cells with semiannular bands, the bands at times incomplete.
Spores verrucose, brown, 14–17 µm in diam. Elaters feebly tortuous to nearly straight, ca. 7.5–9 µm wide, bispiral.
Distribution and Ecology : Bipolar, in the Holarctic with a wide, Arctic–alpine distribution; in the Southern Hemisphere known from the southernmost tip of South America, South Georgia, Falkland Islands (Engel, 1990a), Antarctica, where “it is one of the most widespread and abundant of all Antarctic liverworts...” (Bednarek-Ochyra et al., 2000, p. 121) and New Zealand (South Island, 1065–1675 m).
Schuster (1968b, p. 486) stated “in New Zealand the species is restricted to the subalpine scrub zone or tussock zone, usually at elevations of 3500–5500 ft. Associated are several Holarctic taxa (Anthelia juratzkana, Marsupella ustulata s. lat., Cephaloziella arctica subsp. antarctica, Cephalozia bicuspidata s. lat.) as well as Schistochila splachnophylla, Lophozia autoica and several other subantarctic taxa. Usually occurring over exposed, often broken soil, sometimes with Polytrichum.” In the Old Man Ra. with Hygrolembidium at 1370 m (ca. 1 km N of summit of Shingle Creek Road, Otago); also over soil among tussocks with Marsupella sprucei and Diplophyllum cf. dioicum (Foggy Peak, Torlesse Ra., Canterbury, 1730 m).
Comments : The species has bifid leaves with thin-walled cells and minute to small trigones. The gemmae, typically present in New Zealand populations, are bright red and in exposed sites are copiously produced. This is the only one of our species with a ventral band of such smaller mycorrhizal cells in the stem. These cells, with maturity, become brownish and eventually, at least in part, disintegrate. The species is paroecious.
