Hyalolepidozia S.W.Arnell ex Grolle
Hyalolepidozia S.W.Arnell ex Grolle, Rev. Bryol. Lichénol. 32: 179. 1964 (1963).
Hyalolepidozia S.W.Arnell, Bot. Not. 115(2): 203. 1962, nom. inval., sin. descr. lat.
Type: Hyalolepidozia bicuspidata (C.Massal.) S.W.Arnellex Grolle (≡Lepidozia bicuspidata C.Massal.)
Plants anisophyllous, soft, creeping, whitish to pale green, lacking secondary wall pigments, very small. Branching irregular, the branches nearly exclusively lateral-intercalary and less commonly, ventral-intercalary; creeping or geotropic stolons developed; terminal branching very rare, of Frullania and Microlepidozia types. Stems delicate, soft and rather fleshy, the cortex in 6(7) rows of very large, inflated cells with thin to only weakly thickened walls, forming a conspicuous hyalodermis; medullary cells much smaller, in 8–13 rows, strongly elongated. Rhizoids at underleaf bases. Leaves remote to sporadically contiguous, the insertion transverse to weakly or distinctly incubous, the insertion extending to stem midline dorsally or virtually so, the orientation at times transverse (the leaves then vertical); leaves concave, composed of relatively few cells, nearly uniformly bilobed to 0.45–0.65 (leaves sporadically 3-lobed in Hyalolepidozia microphylla), the lobes narrowly acute, 3–4 cells wide at base, terminating in a single cell or a uniseriate row of 2–3 cells; disc typically 2–4 cells high. Cells of leaves mostly oblong, thin-walled to feebly thick-walled, lacking trigones; surface smooth or delicately papillose. Underleaves much smaller than leaves, bilobed or, if asymmetrically 3-lobed (rare), then with 1–2 of the lobes reduced; disc usually 1–2(3) cells high. Asexual reproduction lacking.
Dioecious or autoecious. Androecia on short lateral- and ventral-intercalary branches, subspicate; bracts concave, bifid to ca. 0.5; antheridia 1 per bract, the stalk biseriate; bracteoles lacking antheridia. Gynoecia on short lateral- and ventral-intercalary branches; bracts of innermost series much larger than leaves, 2(3)-dentate or lobed up to 0.45; lobes terminating in 2 laterally juxtaposed cells, a single cell or a uniseriate row of 2 cells, the lobe margins entire or with a few teeth toward base; disc margins entire or with a few small teeth or irregularly crenulate by projecting upper ends of cells, at times with a lobule near base of 1 or both main lobes; bracteole similar to bracts. Perianth long-exserted, fusiform to linear, terete below, trigonous above, narrowing to the not or contracted mouth, the mouth lobulate, the lobules each terminating in a single cell or the summit crenulate by cells laterally free for varying distances, the terminal cells somewhat elongated, rounded at the summit and not sharp.
Seta with 8 rows of large outer cells and 13 rows of much smaller internal cells. Capsule wall 2- or 3-stratose; outer layer of cells with two-phase development, the primary walls lacking pigmented thickenings, the secondary walls with thin continuous sheets of pigmented wall material and with nodular thickenings present and low or only feebly developed, lending the walls a sinuous appearance; inner cells with nodular to feebly extending thickenings common, with a few complete semiannular bands.
Spores with low but sharply defined, close papillae and short, simple or at times furcate vermiform ridges that at times anastomose; spore:elater diam. ratio 1–1.2:1. Elaters rather rigid, short, only 91–142 µm long, bispiral.
A genus of two species. Hyalolepidozia bicuspidata (C.Massal.) S.W.Arnellex Grolle is amphi-Atlantic-temperate, occurring in South Africa, Table Mtn., Falkland Islands (see Engel, 1990a), southern South America (see Engel, 1978), Juan Fernandez and “Frai Jorge” (northern Chile). A second species occurs in New Zealand. Hyalolepidozia longiscypha (Taylor) Grolle of western Australia was transferred to Paracromastigum by Schuster and Engel (1996).
Reference: Schuster (2000a).
