Telaranea parvifolia (Steph.) J.J.Engel & G.L.Merr.

Thouvenot, Louis & Müller, Frank, 2021, Contribution to the bryophyte flora of New Caledonia IV. Species new to the country, new localities together with taxonomic notes, Cryptogamie, Bryologie 20 (13), pp. 181-196 : 186

Telaranea parvifolia (Steph.) J.J.Engel & G.L.Merr.

( Fig. 1 A-H)

SPECIMENS EXAMINED. — New Caledonia. South Province, La Foa, Dogny Plateau, 21°37’27”S, 165°52’27”E, in a wet forest at the top of a small valley, 950 m, 24.X.2019, Thouvenot NC2617 PC[(PC0712107)]; Parc Provincial de la Rivière Bleue, along the path from the Refuge de la Rivière Bleue to Haute Pourina, rainforest, on rotten wood, c. 800 m, 06.IX.2001, Müller NC178.

DESCRIPTION

based on the specimen Thouvenot NC2617 ( Fig. 1 A-H) Habit

Plant growing in very dense mats made of interwoven stems frequently branching, primary stems producing ventral intercalary secondary stems ( Bazzania - type branching); all kinds of stem leafy and in turn densely pinnate, with lateral branches of Frullania - type often whiplike.

Stem

Somewhat dorsi-ventrally flattened, with a strong differentiation: the single external layer of larger cortical cells, 35-65 µm wide, firm walled, sharply distinct from the numerous medullary cells, thicker walled, smaller, 6-25 µm wide.

Leaves

Fully developed stem leaves 4-lobed, convex, 200-250 µm long, 250 µm wide, incubous, inserted in a straight line, the two homologue leaves widely separated abaxially by two lines of epidermal cells, the leaf discs transversally rectangular, 8 cells wide, 3-4 cells high, short rectangular, moderately thick-walled, the marginal cells smaller, the leaf lobes small, the ventral smallest, erect or somewhat curved, made of one file of 1-3 cells short rectangular, 1- or 2-celled at bases, the terminal cells narrowly rounded at apices; the branch leaves variable, typically imbricate or erecto-patent, oblong to oval, 3-lobed, lobes 1-2 celled.

Underleaves

Fully developed stem underleaves about as wide as the stem, 100-120 µm long, 250 µm wide, the disc 1-2 cells high, with four small lobes, 1-2 cells long; the branch underleaves variable, when fully developed, disc 1-2 cells high, with three 1-celled lobes.

COMMENTS

This endemic Lepidoziaceae was only known from the type collected by Mrs Louise Le Rat in July 1909 in the Dogny Massif (PC0102356). The observation of a fresh specimen allows to complete the description by Engel & Smith-Merrill (2004) and to provide illustrations. The species is noteworthy by the width of the stems that occupy not less than half the whole leafy shoots, so that the leaves are inconspicuous at naked eyes, slightly projecting beyond the stem edge.

Figures

FIG. 1. — A-H: Telaranea parvifolia (Steph.) J.J.Engel & G.L.Merr. A, shoot, dorsal view; B, C, stem transverse sections; D, main stem leaf; E, main stem underleaf; F, branch leaf; G, H, branch underleaves.From Thouvenot NC2617. I-L: Lejeunea leratii (Steph.) Mizut. I, shoot, ventral view; J, lobule ventral view; K, underleaf; L, leaf cell. From Thouvenot NC2741. M, N, Balantiopsis montana (Colenso) J.J.Engel & G.L.Merr. M, leaf, dorsal view (lobule cells omitted); N, underleaf. From Laudereau NC2780. Scale bars: A, M, N, 200 µm; B-H, J, L, 100 µm; I, 500 µm; K, 20 µm.