Anthelia juratzkana (Limpr.) Trevis.
Jungermannia nivalis Sw. in F.Weber & D.Mohr, Index Mus. Pl. Crypt. 5. 1803, nom. dub.
Jungermannia juratzkana Limpr. in Cohn, Krypt.-Fl. Schlesien 1: 289. 1876.
Anthelia juratzkana (Limpr.) Trevis., Mem. Reale Ist. Lombardo Sci. Lett. III, 4: 416. 1877.
Type: Germany, Riesengebirge, Limpricht.
Plants stiff and brittle, terete, filiform and slender, densely leafy, often light green toward shoot apices, brownish below, forming thin, loosely gregarious, silvery, bleached whitish small patches or crusts, or as isolated, dwarf, whitish plants, at times suberect and caespitose with other hepatics, minute, to 350 µm wide with leaves. Branching remote and with 1–4 branches per axis to rather freely pinnate, the branches of the Frullania type, often short; ventral-intercalary branches rare, microphyllous, stoloniform. Stems with dorsal and lateral sides with low, irregular, lamella-like ridges or strips of cells, the strips of cells contiguous with accessory cells on the abaxial surface of the leaf base, the stem in cross section with exposed wall of the hyaloderm cells notably thin, hyaline, bulging, often irregular in size and bubble-like, eventually collapsing with age, the subepidermal cells in 1–2 layers of thick-walled, pigmented cells, grading into a medulla of thin-walled cells. Rhizoids common, from stem in a rather broad zone at base of underleaf, wide for plant size, stiff. Leaves usually densely imbricate, concave to subcanaliculate, the insertion transverse but at times feebly succubous on laxer shoots, unistratose or locally bistratose in basal sector and then the leaf lamina crenulate in profile, the leaves elliptic to cuneate-quadrate, 200–325 µm wide × 240–350 µm long, bifid to 0.5–0.7; lobes erect, plane or feebly sulcate, narrowly acute, often apiculate, 8–14 cells wide at base, terminating in a single cell or a uniseriate row of 2 cells; lamina margins entire or feebly crenulate with slightly projecting shoulders of marginal cells. Cells moderately firm-walled, the marginal cells for the most part quadrate to short-rectangular, the cells of lobe base 13–17 µm wide × 20–25 µm long; surface smooth. Oil-bodies lacking. Underleaves virtually indistinguishable from leaves, except bilobed nearly to the base (the lamina 1–3 cells high) and with rhizoids at base. Fungal partner absent.
Paroecious. Gametangia terminal on leading shoots or on lateral branches, initially clavate or capitate, the densely imbricate bracts and bracteoles in several series, leaf-like, larger, bilobed to at least 0.5, the decolorate lobes and margins crenulate to serrulate-crenulate with projecting cells. Perianth short-ovoid, deeply lobed, the lobes serrulate-denticulate, almost included up to time of capsule dehiscence, closely sheathed by the erect, involute bracts.
Capsule (Schuster, 1974a) with outer layer of cells subquadrate or short-oblong, with 1–2(3) nodose thickenings on the longer walls, (0)1–2 on shorter walls, toward capsule base the epidermal cells more irregular, elongated, with sheet-like thickenings on longer walls, only locally nodular; inner layer of cells with narrowly rectangular, incomplete or weakly defined semiannular bands.
Spores delicately papillose, (15)16–18(20) µm in diam. Elaters 7–8.5 µm wide, with 2 or 3 narrow spirals.
Distribution and Ecology : Cosmopolitan in alpine and Arctic regions, southward to Spain, northern Italy, central Japan, Colorado and other montane areas at similar latitudes; disjunct in alpine areas from Mexico to Venezuela, Ecuador and Bolivia, to Tierra del Fuego, South Georgia, South Orkney Islands, South Shetland Islands, Livingston Island (Bednarek-Ochyra et al., 2000); also from Japan to Indonesia to alpine New Guinea, where it occurs at 3475–3500 m (Schuster, 1968b, 1974a) and to alpine areas of New Zealand. Also in Tanzania (Ochyra and Pócs, 1992). In New Zealand: South Island (1260–1900 m), North Island (1715–1790 m). Known from Fiordland (Mt. Burns), Otago (Old Man Ra., Dunstan Mtns., Aspiring Natl. Park), Westland (Galena Ridge), Canterbury (Mt. Taylor, Arthur’s Pass), Western Nelson (Mt. Arthur) and Volcanic Plateau (Mt. Ruapehu) EPs. It is most frequent in central and western Otago and appears to be absent from the high mountains of Marlborough.
In New Zealand with the identical ecology seen in all other regions: usually on raw soil, often frost-heaved, in shallow valleys where snow lies late into the summer. At Avalanche Peak (Scotts Track, Arthur’s Pass Natl. Park, 1650 m) plants occurred over a thick soil layer between boulders in the alpine zone. On the Young Ra. (Aspiring Natl. Park, 1900 m) it occurred on a flat soil terrace that has late snow lie, in Poa colensoi grassland with Raoulia grandiflora, Gentianella divisa and Zotovia colensoi. Also in penalpine scrub consisting mainly of Chionochloa, Dracophyllum and Hebe (below and W of Mt. Shrimpton, Mt. Aspiring Natl. Park, 1370–1470 m); at this station plants occurred over bare soil with Diplophyllum. On the summit of Mt. Arthur (Nelson, 1795 m) it is on the walls of a sinkhole, associated with Poa colensoi, Luzula colensoi and Chionohebe pulvinaris. On Mt. Ruapehu (vicinity of Turoa ski area, near SE Basin, Tongariro Natl. Park, ca. 1715–1790 m) the species occurs as scattered colonies on bare, dry soil of raised rocky soil beds that are between a seepage area and a stream in an area with alpine cushion vegetation. Commonly associated with Andreaea sp., Cephaloziella sp., Conostomum pusillum, Dicranum aucklandicum, Herzogobryum teres, Nothogymnomitrion erosum, Notoligotrichum australe and Pachyschistochila nivicola.
Comments : We have seen only the whitish, dwarfed phenotypes in New Zealand, and these occur in small patches, usually over bare soil, but the shoots, when creeping amidst other bryophytes and with crowding, sometimes may become erect. Although very small (the main stems only 3–6 mm long), the plants are in many cases rather freely pinnately branched, with branches all of the Frullania type (Fig. 125: 1). The plants have the usual strongly water-repellent, whitish, light-reflecting surface so typical of the genus as a whole. Schuster (1974a, p. 639) states “plants of A. juratzkana are often somewhat covered by a pruinose or whitish secretion, consisting of crystalline filaments or needles (teste Müller, 1951–58), which is not a fungus, although it has been considered to be of fungal origin. However, in the living plant, at least, it appears to be in the form of a thin, opaque, whitish layer which renders the plants nearly waterproof...” Plants can be easily overlooked as a whitish crustose lichen.
The stem anatomy is noteworthy. The dorsal and lateral sides of the stem have low, irregular, lamella-like ridges or strips of cells. The strips of cells are contiguous with those on the abaxial surface of the leaf lamina, i.e., below the level of the sinus. The strips of cells are best observed in the distal sector of the shoot and are less conspicuous on older, lower, pigmented sectors. In stem cross section the strips of cells may be seen as bulging, often irregular, often huge cells accessory to the hyaloderm cells (Fig. 125: 8, 9). On lower, pigmented sectors of the shoot the exposed wall of the hyaloderm cells for the most part collapses toward the cell interior and the accessory cells have been sloughed off. The thickened radial and inner tangential walls of the cortical cells remain, lending an irregular surface to the stem (Fig. 125: 10).
The leaf lamina is often locally bistratose (Fig. 125: 5, cross section). The accessory cells occur in an irregular field on the abaxial surface and are bulging and hemispherical vs. the elongate cells of the lamina (Fig. 125: 6, surface view of field). The hemispherical cells lend the leaf lamina a distinctly crenulate profile.
The populations from the Antarctic Peninsula differ from both the New Zealand representatives and those of the Northern Hemisphere by having a “hyaloderm of firm-walled cells” (Bednarek-Ochyra et al., 2000, p. 97) that are thickened even on the exposed face of the cells (Bednarek-Ochyra et al., 2000, fig. 42: 11). The hyaloderm of New Zealand plants consists of cells that are very thin-walled, at least on the outer tangential wall (Fig. 125: 8, 9). Also, epidermal cells of the stem are regular in size and shape and do not bulge in the Antarctic populations (Bednarek-Ochyra et al., 2000, fig. 42: 11). In the New Zealand populations the strips and ridges of cells on the stem are seen in stem cross section as thin-walled, accessory cells that are irregular in size and shape, and freely bulge (Fig. 125: 8, 9). The hyaloderm cells in Northern Hemisphere populations are regular in shape and distinctly bulge (Schuster, 2000a, fig. 52: 2). The underleaves of the Antarctic populations are more shallowly divided than in New Zealand plants (compare fig. 42: 2, 6, 7 in Bednarek-Ochyra et al. [2000] with Fig. 125: 2, 4). Schuster (1974a) illustrated underleaves from North American material and showed one underleaf with a distinct lamina (fig. 434: 8) and another with a lamina 4 cells high (fig. 435: 5).
