Trichocolea mollissima (Hook.f. & Taylor) Gottsche
Jungermannia mollissima Hook.f. & Taylor, London J. Bot. 3: 390. 1844.
Trichocolea mollissima (Hook.f. & Taylor) Gottsche, Ann. Sci. Nat. Bot. V. l: 132. 1864.
Type: Auckland Is., Hooker.
Trichocolea elegans Colenso, Trans. & Proc. New Zealand Inst. 20: 251. 1888 (1887), non T. elegans Lehm., Nov. Min. Cogn. Stirp. Pug. 10: 8. 1857.
Type: New Zealand, Waipawa Co., Norsewood, 1886, ? Colenso; ibid., Waipawa Co., near Dannevirke, May 1887, Colenso; ibid., Hawke’s Bay Co., Glenross, October 1887, Balfour.
Trichocolea australis Steph., Sp. Hepat. 4: 62. 1909.
Type: New Zealand, sin. coll.
Plants with an aspect of a plumosely branched pleurocarpous moss, ascending or, when arboreal, pendulous, pale yellowish green to ± pale cream, robust, to 3.5 cm wide, including branches. Branches regularly 3-pinnate, tertiary branches uniformly arising from lowest secondary branches, the leading axis retaining its dominance, the main branches progressively less vigorous, the primary branches widely spreading; in suberect, particularly vigorous plants the pinnae drooping, convex and oriented perpendicular to plane of main axis. Branches julaceous, with a woolly appearance, with all sides appearing as a mass of interwoven cilia. Stems stiff, paraphyllia present, often dense, often branched, with cells similar to those of leaf cilia. Rhizoids usually absent. Leaves of stem firmly attached, stiffly and widely spreading but with lobes and cilia arching toward shoot apex, the leaf thus somewhat hand-like, the leaves in situ often appearing as a dense, brushed fringe of cilia, the individual lobes hardly discernible, the leaves on the stem distant to approximate, becoming imbricate on branches, semiamplexicaul, the insertion transverse to weakly succubous, suborbicular to subreniform, divided into 4–6 erect, pinnulate lobes (the lobes in ventral sector of leaf weakly larger), each lobe actually unequally (2)3-fid, consisting of a stronger, erect, regularly pinnulate division and 1–2 small, irregular, abaxially displaced, accessory divisions that are (1)2–4 cells wide at the base, and arched in same direction as main lobes, the divisions armed with pairs of opposing branched cilia. Lobes caudate, usually ± distinctly pinnulate (best seen in adaxial view), with numerous capillary segments and cilia, the ventral lobes 2–5 cells wide at base, with 2–3 tiers of laterally juxtaposed cells basal to the uniseriate row of 5–6(7) cells; cells of uniseriate row tapering, with swollen, dilated septa, thick-walled, becoming progressively longer and narrower toward lobe apices and ultimately becoming capillary, the surface finely striolate-papillose, the penultimate cell 10–12 µm wide × 60–98 µm long; terminal cell of uniseriate row often curved to sinuous, finely tapering to a sharp point, 7–12 µm wide, (90)100–150(170 or more) µm long, usually thick-walled in the tip, the surface smooth to finely striate-papillose; margins of lobes armed with pairs of opposing cilia, the cilia usually branched, often repeatedly, the armature in basal sector of lobe inserted on the abaxial surface of lobe and abaxially patent, the armature in distal sector of lobe ± in same plane as lobe, often appearing as if brushed in the same direction as the lobe; marginal cilia of lobe uniformly uniseriate throughout, the cells similar to those of the uniseriate sector of leaf lobes; sinus bases plane and not reflexed. Disc weakly asymmetric, consisting of a low, wide strip 2–5 cells high (from base to sinuses); margins of disc with branched cilia similar to those of lobes, the cilia sometimes abaxially displaced and lying at right angles to the disc plane. Cells of disc ± thick-walled, rarely with small trigones, the cells elongated, in somewhat regular tiers, in lamina middle 14–24 µm wide × 34–54 µm long; surface long-striolate, with only a few papillae. Oil-bodies pale smokey grey, the paired cells at lobe bases with 11–15(20) per cell, irregularly granular-papillose, the tiny spherules distinct but faint and variable in size, the oil-bodies irregular in shape: subglobose to ovoid to broad-elliptic, some potato-shaped and with irregular bulges, 4.8–6.2 × 7.7–10.6 µm, spherical ones 3.8–6.7 µm in diam. Underleaves somewhat smaller than leaves, free or narrowly connate on one side, subreniform, quadrifid, the median sinus often deeper (then bisbifid), the armature similar to leaves; disc 3–4 cells high, at times 2 cells high below median sinus. Fungal partner absent.
Androecia intercalary on primary and secondary branches, hardly differentiated, the bracts divided to ca. 0.7–0.8, similar to leaves except somewhat ventricose at base and the disc higher dorsally, the abaxial face of lamina devoid of surface armature; antheridia large for bract size, 1–2 per bract, the stalk to ca. 18 cells long, biseriate. Coelocaule on main shoot or short to rather long branches, but becoming axillary or pseudolateral (through development, respectively, of 2 or 1 subfloral branches), the coelocaule cylindrical to narrowly clavate, densely paraphyllose.
Seta becoming hollow at maturity, ca. 21 cells in diam., the epidermal cells in numerous rows, smaller, the inner cells gradually becoming larger toward seta middle. Capsule ellipsoidal, the wall 78–92 µm thick, of 7–8 layers; outer layer of cells large, hyaline, ephemeral, lacking thickenings; innermost layer with very irregularly oriented, various-sized cells, with semiannular bands common, rather narrow, usually complete, rarely forked.
Spores 13.5–13.9 µm in diam., with low but sharply defined, close papillae and short-vermiculate markings. Elaters somewhat contorted, bluntly pointed at the ends, short, 8.6–11.9 µm wide, bispiral, the spirals 3.8–4.2 µm wide.
Distribution and Ecology : New Zealand: Auckland Islands, Campbell Island, Stewart Island (0–340 m), South Island (0–915 m), North Island (150–1040 m), Chatham Islands (160–260 m); Australia: Tasmania, Victoria, New South Wales. In New Zealand known from Rakiura (Stewart Island, Solander Island), Fiordland, Southern North Island, Volcanic Plateau, Taranaki, Gisborne, Auckland and Northland EPs.
Common throughout our area in a variety of forest types from sea level to ca. 950 m, especially those that are rich and particularly wet. It occurs on the forest floor often in damp leaf litter (then erect), in often thick masses on logs that are totally bryophyte covered, on old stumps and tree bases (then horizontal to ± pendulous), on tree-fern trunks, and on bryophyte-covered banks (at times along stream courses). It tolerates particularly wet, terricolous niches such as mucky soil in boggy areas, etc. It also may be arboreal (hosts include Nothofagus menziesii, Weinmannia racemosa and Neomyrtus pedunculatus) and is then pendulous in hanging sheets of bryophytes. It is occasional on vertical rock walls, rock ledges, or wet rock faces (especially where some soil and decaying vegetation have accumulated). Also in relatively open, boggy areas where it occurs at the sides of wet depressions and on bryophyte-covered banks. Accompanying species are Adelanthus falcatus, Breutelia pendula, Canalohypopterygium tamariscinum, Cratoneuropsis relaxa, Cyathophorum bulbosum, Dicranoloma billardierei, Distichophyllum pulchellum, Heteroscyphus billardierei, Hypnodendron comosum, Leptotheca gaudichaudii, Lepidogyna hodgsoniae, Lepidozia pendulina, L. spinosissima, Lepidolaena palpebrifolia, L. taylorii, Metzgeria leptoneura, Plagiochila circinalis, P. gigantea, P. incurvicolla, P. lyallii, P. retrospectans, P. stephensoniana, P. strombifolia, Ptychomnion aciculare, Pyrrhobryum mnioides, Temnoma pulchellum, Thuidium furfurosum and Weymouthia cochlearifolia.
Comments : Smaller, weakly developed plants may be confused with Trichocolea hatcheri, and must be identified with care. Also, hygrophilous plants growing on mucky soils often appear “etiolated” and spindly and have fewer tertiary branches. In such phases cells of the cilia have only slightly thickened walls, and have septa that are only slightly thickened. The cells of the uniseriate row, including the terminal cell, are often more papillose. The terminal cell tapers, but is narrowly rounded and neither sharp nor thickened at the tip. The terminal cell, however, is long and narrow, as in more well-developed material of the species.
Most often confused with Lepidogyna hodgsoniae as the two species are about the same size and can occur in similar niches in forest, are often the same yellow-green color, are both regularly 3-pinnate, and both ciliate. Trichocolea mollissima lacks lobules, and the cilia are branched while in Lepidogyna they are unbranched.
For the confusion in names applied to this species and Trichocolea hatcheri, see under that species.
