DIAGNOSIS. — Dioicous. Thallus very fleshy, unwinged. Axis circular to biconvex, branches with rounded margins. Male branches stalked.

TYPE. — Madagascar. Alaotra-Mangoro, Vohimana Reserve, Grande Cascade, 18°55’43.6”S 49°29’56.6”E, 849 m, 30. VI.2012, Reeb MTV1246* (holo-, PC [PC 0771050]; iso-, PC [PC 0763876], TAN).

ETYMOLOGY. — Dedicated to Gaspard Reeb-Leurent, born 21/07/2015.

FURTHER SPECIMENS EXAMINED. — Madagascar. Alaotra-Mangoro, Vohimana Reserve, Grande Cascade, 18°55’43.6”S, 49°29’56.6”E, 849 m, 30.VI.2012, Reeb MTV1257 (PC, TAN); Maromizaha Reserve, 18°58’53.02”S, 48°27’50.1”E, 1002 m, 08.VII.2012, Reeb MTM12124 * (PC, TAN), 18°58’53.10”S, 48°27’51”E, 921 m, 08.VII.2012, Reeb MTM12127A *, MTM12133 *(PC0763885), MTM12134 * (PC0763884, TAN); Analanjirofo, Mananara Nord, E slope of Mahavoho hills, 16°27’S, 49°46.9’47.5”E, 220-300 m, 14.VIII.1998, Pócs & Szabo 9878/W (EGR).

DISTRIBUTION. — Alaotra-Mangoro and Analanjirofo regions of Madagascar.

HABITAT. — On rocks or boulders sometimes covered with a humus layer, in humid evergreen lowland and montane forests, between about 200 and 1000 m.

Dioicous.

Dull olive green to green when fresh, green to yellow brown in herbarium, very fleshy, rigid but not leathery (easily breaking when manipulated), to 2 cm long, 1-3-pinnate, not palmate, branches alternate to subopposite, reiterations sometimes present, stolons common, branches mostly wider than the main axis.

Irregularly defined to well-defined in mature thalli, width variable, in cross section circular to ellipsoid at the base, circular to biconvex in the middle, 7-9(-16) cells thick, margins obtuse to rounded, not winged, epidermis cells 3-4× smaller than inner cells.

To 7 mm long, often overlapping.

Tongue-shaped to oblong, often sinuose (horizontally curved), to 6 mm long and 1.8 mm wide, in cross section plano-convex, 5-6(-7) cells thick, margins obtuse, not winged, epidermis cells 2-3× smaller than inner cells, branch apex rounded.

Apical, not persistent.

Not seen.

On the main axis, solitary, stalked, with a scale-like wing narrower than the axis, the wing crenulate by larger cells.

Laterally inserted, straight, bordered by a ciliate, scale-like wing.

Occasionally present, 2-celled.