Telaranea inaequalis R.M.Schust.
Telaranea inaequalis R.M.Schust., Beih. Nova Hedwigia 118: 225. f. 76. 2000, nom. nud. (sin. descr. lat.).
Telaranea inaequalis R.M.Schust. ex J.J.Engel & Merrill, Fieldiana, Bot. 44: 117. f. 37. 2004.
Holotype: Tasmania, Gordon River, Sir John Falls, just upriver from Butler Is., sea level, Engel 14685B (F); isotype: (HO).
[Fig. 77: 4, oil-bodies, p. 355; Fig. 78]
Plants exceedingly delicate, loosely creeping, the leaf lobes minutely thread-like in appearance, whitish green and nitid; shoots minute, to 1.1 mm wide with leaves. Branching occasional, irregular, of the Frullania type; branch half-leaf undivided, leaf-lobe-like; first branch underleaf similar to normal stem underleaves, symmetrically bilobed, the lobes 2–3 cells long, terminating in a slime papilla, inserted on ventral-lateral side of branch just above the base. Flagelliform and stoloniform branches apparently lacking, or rare. Ventral-intercalary branches common, long and leafy. Stems delicate, straight and wiry, rather slender for plant size, the cortical cells in surface view and cross section moderately and evenly thick-walled, in 6 rows (the dorsal larger than the ventral rows); medullary cells in 3(5) rows, smaller, moderately and evenly thick-walled. Main shoots with 2 cortical cells intervening between successive leaves on either side. Rhizoids very thick-walled, from underleaf cells. Leaves distant, widely and laxly spreading, the insertion transverse to at times weakly succubous, consistently bifid essentially to the base (the basal cells scarcely connate), the longer lobes 505–735 µm long, the ventral lobes shorter. Lobes thread-like, not or scarcely tapering, moderately to strongly divergent, flexuous, not disposed in regular ranks, uniseriate throughout, unequal in length: the dorsal (7)8–9 cells long, the ventral 7–8 cells long (not including secondarily divided cells at lobe tips); lobe cells subequal in length except at the tip, the basal cells 22–28 µm wide × 90–120 µm long, the next cell 18–24 µm wide × 78–108(120) µm long, the terminal cell minute, ca. 0.25 the length of the penultimate cell, occasionally with repeated cell divisions at the lobe apex resulting in 3–5 short cells, the tip at times becoming detached; cell walls ± thick-walled, the transverse septa thickened in the corners and feebly swollen and projecting, especially in basal half of lobe, the septa in distal portion of lobe at times weakly constricted; surface smooth. Oil-bodies occupying a very small portion of cell, hyaline and somewhat glistening, (1)2–3(4) per lobe cell, subglobose to elliptic, coarsely papillose, the spherules distinctly protruding. Underleaves small and inconspicuous, bifid, the lobes parallel to somewhat connivent, 2–3 cells long, terminating in a slime papilla, the “disc” formed of the two partially connate lobe cells. Asexual reproduction absent.
Plants dioecious. Androecia on abbreviated, tiny, inconspicuous, ventral-intercalary, spicate branches; bracts closely imbricate, the entire bract deeply concave, bilobed, each lobe terminating in a single cell, or, more often, a uniseriate row of 2 thick-walled cells, the tip cell particularly thick-walled; lamina cells non-tiered, irregular in shape and arrangement, the lamina margins crenulate; antheridia 1 per bract, large for bract size, the stalk uniseriate; bracteolar antheridia absent. Gynoecia not seen.
Distribution and Ecology : Endemic to New Zealand: Stewart Island, South Island (0–900 m); Australia: Tasmania. Known from Rakiura (Pegasus Creek), Fiordland (Bowen Falls) and Western Nelson (Stockton Plateau) EPs.
At Stockton, the species is abundant on sandstone rock overhangs in sharply incised stream valleys, on vertical or overhanging surfaces kept moist by seepage. There it can be the dominant bryophyte, forming dense mats on rock and at the front of overhangs, forming tapering “stalactites” up to 1 m long composed of vascular plant roots (e.g., Forstera mackayi), this species, Acromastigum marginatum and A. mooreanum. Other accompanying species on the rock walls are Kurzia hippuroides, Pallaviciniaaff.rubristipa, Paracromastigum furcifolium, Psiloclada clandestina, Rhizogonium pennatum, Riccardia perspicua, Zoopsis bicruris and Z. setulosa.
Comments : Telaranea inaequalis is immediately distinct from T. herzogii by the consistently unequally bilobed leaves, the flexuous, non-tapering lobes 6–9 cells long (Fig. 78: 4) and the equally and symmetrically bilobed first branch underleaf (Fig. 78: 3). See under T. herzogii for additional comments.
Telaranea inaequalis is remarkably similar gametophytically to T. diacantha (Mont). J.J.Engel & Merrill of the Neotropics and T. major Herzog, a species with a broad distribution ranging from Sri Lanka to the Philippines and Malaysia to Vanuatu. For a discussion see Engel and Merrill (2004).
