Telaranea praenitens (Lehm. & Lindenb.) E.A.Hodgs.
Jungermannia praenitens Lehm. & Lindenb. in Lehm., Nov. Min. Cogn. Stirp. Pug. 6: 27. 1834.
Lepidozia praenitens (Lehm. & Lindenb.) Gottsche, Lindenb. & Nees, Syn. Hepat. 206. 1845.
Mastigophora praenitens (Lehm. & Lindenb.) Trevis., Mem. Reale Ist. Lombardo Sci. Lett. III, 4: 416. 1877.
Telaranea praenitens (Lehm. & Lindenb.) E.A.Hodgs., Rec. Domin. Mus. 4: 107. 1962.
Type: New Zealand, South Is., Dusky Bay, Menzies (G!, S! [3 seen]).
Plants with a rather spiny appearance, soft, flexuous yet firm, loosely prostrate, often in dense, compact mats, dirty yellowish green, nitid when dry; shoots small to medium, to 0.9 cm wide, including branches. Branching mostly regular and loosely to less often quite densely 1-pinnate, the branches remaining rather short, normally determinate, not much differing in length (rather than plumose), the branches of the Frullania type; branch half-leaf bilobed, narrowly rectangular to cuneate (then with lobes diverging), entire (or with one or both margins toothed in var. dentifolia); first branch underleaf undivided and ciliiform, inserted on ventral side of branch near juncture of branch and main axis. Ventral-intercalary branches occasional, often becoming leading shoots and leafy throughout. Stems with cortical cells markedly differentiated, the radial walls thin, the outer wall somewhat thickened, in 12–13 rows, those on ventral side of stem a little smaller; cortical cells in section larger than the numerous (ca. 50–65) medullary cells. Rhizoids not seen. Leaves on main shoot rigid, at least the disc widely spreading, distant to loosely imbricate, plane to moderately concave, the lobes somewhat incurved, the insertion moderately to distinctly incubous; leaves 510–870 µm wide × 455–595 µm long, moderately to distinctly asymmetric (the dorsal lobes paired), ± equally and rather deeply palmately 4-lobed to ca. 0.5–0.65 (very rarely [1 population] 5–6-lobed), the lobes subequal to somewhat longer than the disc in length. Lobes attenuate, 4 cells wide for 1–3 tiers at extreme base (5–6 cells wide at base in var. dentifolia), biseriate for much of their length, terminating in a short uniseriate row of 2–4(5) cells (typically less than half the length of lobe), the lobe margins contracted at the transition from 4 cells wide to 2 and from 2 cells wide to 1; lobe cells ± firm, moderately thick-walled, the septa thickened in the corners and swollen and projecting from the lobe margins, the lobe cells rectangular and not narrowing distally; surface finely to distinctly striate-papillose. Disc somewhat asymmetrically short-cuneate, 4–5 cells high (from median sinus base to leaf base), 15–16(19) cells wide in distal portion narrowing to 8–10 cells wide in basal portion; margins entire (sporadically toothed in var. dentifolia), the dorsal margin often bluntly denticulate by projecting septa at the ends of cells, ± straight. Cells of disc moderately thick-walled, trigones minute to small, the median disc cells 22–38 µm wide × (38)43–60 µm long, in ± regular tiers or somewhat irregularly arranged; basal 1–2 rows of disc cells larger; surface smooth or faintly striate-papillose distally. Underleaves much smaller than leaves, strongly spreading to subsquarrose, distant, plane, 4(rarely 5)-lobed to ca. 0.5, the lobes ciliiform, straight, 2–3 cells wide at the base, the uniseriate portion formed of 3–4(5) elongated, ± thick-walled cells with thickened septa, often terminating in a slime papilla; disc symmetrically cuneate, 3–4(5) cells high (median sinus), the cells in irregular tiers, the disc 11–17 cells wide in distal portion narrowing to 8–9(12) cells wide at base; margins entire, usually straight.
Plants dioecious. Androecia either terminal on short to moderately long primary or secondary Frullania -type branches or on short, abbreviated, ventral-intercalary, spicate branches; bracts closely imbricate, strongly dorsally assurgent, deeply concave, bilobed to ca. 0.4, the lobes acuminate, terminating in a uniseriate row of 2–4 not to slightly elongated cells; dorsal margin of lamina irregularly crenulate, with a few stalked or sessile slime papillae; bracts monandrous; antheridia large for bract size, the stalk uniseriate; bracteolar antheridia absent. Gynoecia with bracts small for perianth size, those of innermost series concave, broadly ovate to suborbicular, ± regularly 3–4-lobulate, the lobules terminating in a pair of laterally juxtaposed cells or a single cell; lamina composed of ± regularly subrectangular cells, the margin bordered by cells of variable shape, often long and narrow, the apical or free end of marginal cells often divergent and forming a crenulation, the margins thus irregularly crenulate, otherwise with a sporadic unicellular tooth and a few slime papillae; bracteoles of innermost series similar in form and size to bracts. Perianth long-emergent, fusiform, terete in basal and median sectors, the distal sector obscurely trigonous and with 4–5 plicae, the perianth narrowing toward the strongly contracted mouth; mouth cells thick-walled, often sinuate, partially or wholly laterally free, occasionally with a laterally free uniseriate row of 2 cells, the mouth thus denticulate-subciliate, the surface cells immediately below mouth often with their apical end projecting as a blunt, thick-walled tooth; perianth 2–3-stratose in basal portion, the median portion 2-stratose.
Seta with 8 rows of outer cells (each with their free face bulging), surrounding an inner core of 19–20 much smaller cells. Capsule rather long-ellipsoidal, 420–560 µm wide × 980–1260 µm long, the wall 26–34 µm thick, of 3 layers, the outer layer subequal to or slightly less thick than the combined 2 inner layers; outer layer of cells in tiers, rather regularly short-rectangular, with two-phase development, the longitudinal walls with well-defined sheet-like thickenings and nodule-like thickenings (4–6 per cell) alternating with walls that are devoid of thickenings (or with sporadic, local, non-pigmented, nodular swellings), the transverse walls devoid of thickenings; innermost layer of cells ± tiered, irregularly narrowly to broadly rectangular, with semiannular bands common, rather narrow, close, usually complete, at times forked and anastomosing to delimit ill-defined, local fenestrae.
Spores 12–13 µm in diam., the wall yellow-brown, areolate (with a low, delicate, close network of furcate ridges that coalesce and delimit areolae). Elaters rigid, nontortuous, 9.6–12 µm wide, only slightly tapering toward tips, bispiral to tips, the spirals 2.4–3.8 µm wide.
Key to Varieties
Comments : Telaranea praenitens has been widely misunderstood. It is, however, one of the easiest of our species to recognize, marked by the rather deeply palmately lobed leaves (to 0.6), and the minute denticulations formed by the swollen projecting septa on the lobes and disc margins (Fig. 55: 5, 6). In addition, the surface of the lobes is almost always distinctly papillose (Fig. 55: 5, 6).
A noteworthy feature of this species is the scabrous condition of the perianth surface. The cells immediately below the mouth are prorate, their apical ends projecting as blunt, thick-walled teeth (Fig. 55: 9).
Two varieties are recognized for the species, as follows.
