Cheilolejeunea renigastria Pócs, 2021

Pócs, Tamás, 2021, Notes on the bryophytes of Madagascar 3. Six new Lejeuneaceae species, Cryptogamie, Bryologie 20 (8), pp. 129-141 : 130

Cheilolejeunea renigastria Pócs , sp. nov.

( Figs 1 A-F; 7E, F)

Sect. Euosmolejeunea (Spruce) W.Ye, Gradst. & R.L.Zhu, Cryptogamie, Bryologie 36 (4): 324, 2015.

DIAGNOSIS. — Plant comparable to Cheilolejeunea trifaria (Reinw., Blume & Nees) Mizut. 1964 , but differing by its elongate ovate leaf lobes (length-width ratio 5:4, not orbicular) with almost straight ventral margin and with much smaller underleaves with slightly sinuate insertion, wide sinus and rounded lobe ends.

TYPE. — Madagascar, former Antsiranana Province, Sava Region, Marojejy National Park. Elfin forest on the SE ridge near Camp III, at 1830 m elevation, epiphyllous. T. Pócs, with R. E. Magill & C. LaFarge England, 90114/ HY, 26-28.III.1990 (holo-, EGR; iso-, TAN).

ETYMOLOGY. — Named after its reniform underleaves.

DESCRIPTION

In herbarium yellowish-green shoots 0.8-1 mm wide and up to 15 mm long, remotely branching.

Stem

50-100 µm in diameter, with 7 cells of hyalodermis (of which 2 belong to ventral merophyte) and 8-10 medullary cells of equally thick walls.

Rhizoids

Colorless, radially arranged at the base of each underleaf, but not forming a special plate.

Leaves

Spreading, slightly concave, elongate oval, asymmetric, 400- 600 µm long and 320-400 µm wide, length-width ratio 5:4. Lobe apex rounded to subacute, in most cases incurved. Ventral margin almost straight with at least 170° angle to the straight or slightly curved lobule keel. Lobe, lobule and underleaf cells isodiametric or slightly elongate. Median cells 16-25 µm, marginal ones 8-12 µm in diameter, with large but not confluent trigones and smooth surface. Oil bodies in the herbarium specimen not visible. Lobule about ¼ of the lobe length, triangular-ovate, slightly inflated, with an acute, unicellular 2nd tooth with a distal hyaline papilla. 3-4 cells at the distal lobule end between the tooth and margin. Free lobe margin with many relatively small cells.

Underleaves

Reniform, length-width ratio 3:4, width about 4× of the stem and only 60% of the lobe length. Underleaf insertion slightly sinuate, incision ¼-⅓, wide V shaped, lobules with rounded apex. Androecia, archegonia and ways of vegetative reproduction not seen.

Figures

FIG. 1. — Cheilolejeunea renigastria Pócs, sp. nov.: A-C, habit, dorsal and ventral views;D, underleaf; E, leaf; F, median lobe cells. (All from the type). Scale bars: A, B, 1 mm; C, E, 200 µm; D, 100 µm; F, 25 µm.