Lejeunea tubulirostris Pócs, 2021

Pócs, Tamás, 2021, Notes on the bryophytes of Madagascar 3. Six new Lejeuneaceae species, Cryptogamie, Bryologie 20 (8), pp. 129-141 : 136-140

Lejeunea tubulirostris Pócs , sp. nov.

( Figs 6 ; 7C )

DIAGNOSIS. — Two features are characteristic for this species. The very long, tube like perianth beak, which can reach more than 160 µm (6 cells) length, is unique among the African Lejeunea species, although can occur in several Asian taxa (e.g. Lejeunea pectinella Mizut., 1970 ), but even there is never combined with acute lobe form. The other feature: grooved stem with hollows between the ridges of longitudinal cell walls seems to be unique in the whole genus.

TYPUS. — Madagascar, Fianarantsroa prov., Haute Matsiatra reg., Parc national de l’Andringitra. Mossy montane rainforest along a W tributary of Korokoro river, near camp III, 1000-1270 m, epiphyllous, 22°12’40”S, 47°0’E. T. Pócs, G. Kis & A. Szabó 9473/GL, 20-23.IX.1994. (holo-, EGR; iso-, TAN).

ETYMOLOGY. — The name refers to its very long, tubelike perianth beak.

DESCRIPTION

In herbarium pale green shoots are 1.4-1.8 mm wide and up to 15 mm long, pinnately branching.

Stem

80-120 µm, side branches 50-70 µm in diameter, with hyaloderm of 7 cells of which 2 are ventral merophytes and with 12-15 medullary cells with wavy, thin walls. The stem surface is grooved, with deep hollows between the 12-24 µm high ridges formed by the longitudinal cell walls.

Leaves

Triangular ovate with acute apex, spreading horizontally at an angle of 90-120° with the stem.

Lobe cells

Hexagonal, slightly elongate, 30-50 × 24-40 µm, marginal cells 18-25 µm, slightly protruding, forming a weakly crenulate border. Cell walls with small trigones and intermediate thickenings. Lobules ovate, inflate, about ¼ lobe length, with slightly falcate, unicellular tooth and a hyaline papilla at its proximal base ( Fig. 7C ). There are 2-3 cells between the lobule tooth and keel. The free lobule margin usually incurved, consists of only 3-5 cells.

Underleaves

Orbicular, about 4× stem width, split to about half their length, with a V form sinus and 6-8 cells wide and about 6 cells long lobes with obtuse to acute ends. Underleaf base slightly auriculate with sinuate insertion line.

Autoicous

Androecia on short side branches, turning postically 40-60° to the main stem, globose in shape, about 200 µm in diameter and consist of 2-3 pairs of very concave male bracts. Bracteoles not observed. Gynoecia turning in anterior direction,

at 50-75° to the stem. Female bracts and bracteoles about ¾ of the perianth length, with acute lobes. Bract lobule about ⅔ bract length. Bracteole with short (2 cells deep, V shaped) incision.

Perianth ( Fig. 6F )

Oblong-ellipsoid, 600-800 µm long and 300-323 µm wide, terete with 5 equal keels, each with slightly mamillose edge.

Beak ( Fig. 6G )

Tube like, 6 cells (160 µm) long and 3-4 cells (40 µm) wide, straight, with irregularly mamillose mouth. Sporophyte and ways of vegetative reproduction not seen.

Figures

FIG. 6. – Lejeunea tubulirostris Pócs, sp. nov.: A, B, habit, ventral and dorsal views; C, underleaf and lobule; D, basal lobe cells; E, median and marginal lobe cells; F, perianth; G, perianth beak; H, male branch; I, lobule tooth with hyline papilla; J, transversal section of stem (in wet state). (All from the type). Scale bars: A, B, 200 µm; C, F, 100 µm; D, E, I, J, 25 µm; H, 50 µm.

FIG. 7. — Lejeunea geisslerae (Pócs) Pócs.: A, lobule; B, perianth beak. Lejeunea tubulirostris Pócs sp. nov.; C: lobule. Lejeunea mamilliflora Pócs, sp. nov.: D, lobule. Cheilolejeunea renigastria Pócs, sp. nov.: E, lobule; F, transversal section of stem. (A, B from Pócs 9472/AP, all others from their type). Scale bars: A, E, F, 50 µm; B-D, 25 µm.