Andrewsianthus cuspidatus R.M.Schust.
Andrewsianthus squarrosus (S.W.Arnell) Grolle
≡Lophozia squarrosa S.W.Arnell, Results Norweg. Sci. Exped. Tristan da Cunha 42: 20. 1958 (Tristan da Cunha).
Type: New Zealand, South Is., Mt. Cook Natl. Park, Sealy Ra., below Sealy Lakes, ca. 4000 ft., Schuster 49713.
[Fig. 150: 3, 5, oil-bodies, p. 684]
Plants firm, green to greenish brown to yellow-brown, the stems often darker, at times red-brown, the attenuated flagella often similarly, intensely pigmented (but reddish pigments not seen in leaves), the plants occasionally to commonly becoming flagelliform at shoot tips, the shoots to 685(715) µm wide. Branching rather sparing, the branches all lateral-intercalary, axillary in position and not from dorsal end of leaf axil, arising from a ± brownish, creeping, microphyllous rhizome; branches occasionally becoming flagelliform and rhizoidous distally, then in turn giving rise to normal, flexuous, leafy stems. Stems slender for plant size, with cortical cells in surface view often almost guttulate to rounded-oblong, ventrally and latero-ventrally becoming narrower and often longer, the surface rather coarsely striolate but without cellular excrescences, the cortex in cross section in a single layer of very thick-walled cells; medullary cells becoming larger toward middle of stem, hyaline. Rhizoids scattered, few, usually colorless. Leaves rigid, brittle, remote to subcontiguous, widely spreading to squarrose, the base erect and somewhat sheathing, the dorsal sector of leaf antically assurgent and seen edge on or suberect and then the leaf weakly folded (but ecarinate), the leaf lobes widely spreading to squarrose, subtransversely inserted and transversely oriented but somewhat dorsally arched or assurgent, the leaves oblong to oblong-obovate, clearly longer than wide, on sterile stems 2–3× stem width, 265–315 µm wide × 330–415 µm long, bifid (rarely trifid) to 0.2–0.4(0.5); lobes acute, usually narrowly and often sharply so, at times subapiculate to cuspidate, terminating in a single cell or a uniseriate row of 2 (very rarely 3) cells, the tip cell of the lobes wider than long, subisodiametric or to 1.7× longer than wide, the lobe tips often appearing hyaline and scorched; sinus V-shaped but often with base of V narrowly rounded; margins of lobe and lamina crenulate by the dilated, bluntly projecting, anticlinal walls of the marginal cells (even at leaf base), the margins otherwise entire, very rarely with a tooth near dorsal base. Cells with trigones strong, large and bulging, the cells of lobe margins 13–16 µm wide, the median lamina cells rather small, 13–19 µm wide × 17–25(27) µm long, those of leaf base not or hardly larger; surface with coarse, often hemispherical papillae (the largest 5–5.5 × 7–9 µm), becoming striate-papillose toward the base. Oil-bodies (Schuster, 1966c, 2002a) occupying conspicuous portion of cell lumen, 2–4 per cell, rather glistening, faintly granulate at best, very large, variable in form, spherical and 5.5–6.5 µm in diam. to ovoid or ellipsoidal and from 5.5–7 × 6–8 µm to 6–7.5 × 10–13 µm. Oil-bodies (Glenny 9206, 9335) similar throughout leaf, occupying a large portion of the cell lumen, pale smokey grey, the lobes and disc with 2–3 or (2)3–4(5) per cell, even toward lobe tips and at the leaf base, finely to coarsely granular, spherical to broadly ellipsoidal, often somewhat irregularly so, the larger ones often with 1–2 depressions, the oil-bodies 4.5–7 × 6–13 µm, some massive, especially in cells with 2 oil-bodies per cell. Chloroplasts much smaller than oil-bodies. Underleaves consistently present, usually very small (rarely to 0.25× leaf area) and often consisting of a basal tier of 2–4, very thick-walled cells hardly longer than wide, capped with 2 slime papillae, or the thick-walled basal cells with 2 somewhat elongated, thin-walled cells each with a slime papilla, less commonly with a uniseriate row of several cells, the underleaves exceptionally bifid or lamelliform and then to 5 cells wide at base, undivided and with a few marginal small teeth; ventral merophytes relatively narrow, 1–2 cells broad. Asexual reproduction lacking.
Androecia terminal but becoming intercalary on leading leafy axes, laxly spicate, the bracts concave-ventricose throughout; antheridia 1 per bract, the stalk uniseriate. Gynoecia with bracts in 3 series, those of innermost series 2(3)-lobed, at times asymmetrically so, the lobe margins entire or with a tooth or at times with several coarse teeth; bracteole conspicuous, 0.5–0.75× bract area, free from bracts, asymmetrically bilobed, the lobe and lamina margins entire or with a tooth or at times with several coarse teeth. Perianth terete below, bluntly trigonous-triplicate in distal ca. 0.5, contracted to the lobulate mouth, the lobules spinose-dentate to subciliate, with a uniseriate row of up to 3 cells.
Sporophyte not seen.
Distribution and Ecology : New Zealand: Stewart Island (600–690 m), South Island (695–1740 m), North Island (1080–1450 m); Australia: Tasmania. In New Zealand known from Fiordland, Otago (Remarkables, Ocean Peak), Westland (Taipo Valley, Otira Valley), Canterbury (Mt. Cook Natl. Park, upper Godley River, Harman Pass, Torlesse Ra.), Western Nelson (Paparoa Ra., Cobb Valley) and Volcanic Plateau (Mt. Ruapehu) EPs.
This species typically is associated with rock. It occurs over boulder faces, usually where soil or silt has accumulated, particularly in niches such as crevices or pockets, deep in recesses between rocks or under rock overhangs. The boulders or outcrops often occur in rather exposed situations. On Stewart Island it occurs in mosaic communities of penalpine cushion vegetation, herbfields, Chionochloa, prostrate Leptospermum scoparium, Olearia colensoi from 0.5–2 m tall and significant areas of exposed rock (Mt. Rakeahua summit area, 600–690 m). In Canterbury it is found in late snowbank sites at the upper limit of continuous vegetation among Marsippospermum gracile and Poa colensoi rushland or with small Celmisia species. At the south end of Lake Marion (Fiordland Natl. Park, 695 m) it occurred with Herbertus oldfieldianus on the face of a shaded, wet huge boulder near the lake, at the edge of a rather open forest dominated by Nothofagus menziesii. Also found on a rock face in the vicinity of a waterfalls in the upper reaches of a Podocarpus forest (just below Wakefield Falls, Mt. Cook Natl. Park, 870 m). In the Gertrude Valley occurring in a mat of bryophytes on a boulder face in a mosaic of large boulders and dense penalpine scrub (near track entrance to Gertrude Valley, Fiordland Natl. Park, 740 m). In the North Island occurring at Taranaki Falls Track (Tongariro Natl. Park, 1080 m) on the face of a huge boulder at the margin of a creek in a steep-sided canyon through a forest of Nothofagus solandri var. cliffortioides, Griselinia littoralis, Pseudopanax colensoi and Podocarpus hallii. Also in the alpine zone at 1450 m (Blyth Hut to Whakapapa Track not far from Bruce Road to Whakapapa Skifield, Tongariro Natl. Park).
The type is from ca. 1220 m in the Sealy Ra. (Mt. Cook Natl. Park), over damp, shaded rocks along an intermittent watercourse, admixed with Gymnomitrion cuspidatum, Acrolophozia pectinata, Triandrophyllum sp., Jamesoniella sp., Diplophyllum sp., Andreaea sp. and Hymenophyllum multifidum. In alpine sites it is commonly found in with Andreaea acuminata, Bartramia papillata, Cryptochila grandiflora, Herzogobryum teres, Jamesoniella colorata, Radula sainsburiana and Rhacocarpus purpurascens.
Comments : This species is closely allied to Andrewsianthus hodgsoniae. However, the leaf cells in A. cuspidatus are less coarsely papillose than those of A. hodgsoniae, and the stem is nearly smooth, having relatively low, welt-like striae vs. the coarse, hyaline papillae and scattered, conical to finger-like cellular outgrowths of the stem in A. hodgsoniae. The leaves of A. cuspidatus tend to be larger, always clearly longer than broad, and have the very sharp lobes that are commonly distinctly squarrose, giving the plant a different aspect from that of A. hodgsoniae.
Leaf lobe shape is variable, and part of the plasticity is due to the caducous cells at the lobe tip. The lobes terminate in a single cell or a uniseriate row of 2 cells. The tip cell of the lobe is variable, being wider than long, subisodiametric or up to 1.7× longer than wide, and is rounded at the tip or (often) tapers to a rather sharp summit that is thick-walled and ± protracted. In lobes that have a uniseriate row of 2 cells the penultimate cell is often wider than long. The tip cell or both cells of the uniseriate row, when present, often become hyaline, scorched and ultimately collapse. The lobe tip then terminates in a pair of laterally juxtaposed cells and then is of a different shape, i.e., more narrowly rounded. Leaf lobes near the shoot apex are usually less eroded and should be checked for shape.
Andrewsianthus cuspidatus should not be confused with Anastrophyllum papillosum, particularly in those populations of A. cuspidatus that only occasionally become flagelliform at the shoot tips. At least some arching and geotropic flagelliform shoot tips may be found after a careful search; these are never present in Anastrophyllum papillosum. Also, A. cuspidatus has uniformly intercalary branches, the leaf margins are nearly always entire, and only golden brown pigments are developed, at least in the leaves. Anastrophyllum papillosum may produce Frullania -type branches, though rare, but the leaves commonly have a small tooth at the dorsal base and plants develop deep reddish pigmentation.
The species appears to be a close ally of Andrewsianthus marionensis (S.W.Arnell) Grolle (type: Marion Island) =Andrewsianthus squarrosus (S.W.Arnell) Grolle ≡Lophozia squarrosa S.W.Arnell (type: Tristan da Cunha) (see Grolle, 1971a and Váňa, 1985). Schuster (2002a, p. 331) stated that Lophozia squarrosa S.W.Arnell of Tristan da Cunha “appears to be very closely allied, if not identical, with… A. cuspidatus R.M.Schust. ” Schuster (2002a, p. 327, key) mentions “New Zealand, Tristan?” in reference to A. cuspidatus R.M.Schust., indicating some doubt. We would prefer to recognize two distinct species— Andrewsianthus marionensis (S.W.Arnell) Grolle and Tristan da Cunha, and A. cuspidatus from New Zealand.
