Palmorchis fractiflexa Szlach. & Baranow, 2013

Szlachetko, Dariusz L. & Baranow, Przemysław, 2013, New species of Palmorchis Barb. Rodr. (Orchidaceae) from Colombia, Candollea 68 (1), pp. 105-113 : 108-109

2. Palmorchis fractiflexa Szlach. & Baranow , spec. nova

( Fig. 2 ).

Typus: COLOMBIA. Choco: Mpio. de Unguia. Entre Balboa, Jilgal y Titumate , potreros y relictos de bosque de colina, 8°19’N 77°05’W, 20-80 m, 22.XI.2001, R. Bernal, G. Galeano, E. Ballesteros & R. Morales 3094 (holo-: COL [ 505180 ]!).

Differs from all other species of the genus by the fractiflex rachis. In floral structure it is similar to P. pandurata , but the epichile of P. fractiflexa is transversely elliptic, obtuse and the lip callus consists of 3 lamellae running from lip base to the apex, higher in the upper part.

Plants 20(-30) cm tall, leafy. Leaves 3-5, gathered in the upper part of the stem, petiolate; petiole and sheath to 3(-6) cm long; blade to 12(-20) cm long, 3.5(-6) cm wide, lanceolate to oblong-lanceolate, acuminate. Inflorescence a raceme, to 3(-7) cm long, apical, supported basally by 2.5 (-8) cm long, linear, acute spatha; rachis 1.5-2 cm long, somewhat fractiflex, glabrous, flowers distichously arranged. Flowers small, glabrous. Floral bracts to 6 mm long, ovate-lanceolate, acute, glabrous. Pedicel and ovary to 4 mm long, glabrous. Dorsal sepal 7 mm long, 1.2 mm wide, oblongoblanceolate to linear-oblanceolate, acute, with main nerve somewhat thickened on outside, 5-nerved. Petals 6.5 mm long, 1 mm wide, linear-oblanceolate, subfalcate, subacute to subobtuse, 3-nerved. Lateral sepals 7 mm long, 1.2 mm wide, linearlanceolate, subacute, subfalcate, 5-nerved, with the main nerve thickened outside. Lip 6 mm long, subsessile, basally thickened, thickening ciliate, with 3 lamellae running from the base to the apex, much higher in apical half; hypochile 4 mm long, 2.5 mm wide, obtrullate to obovate, with two thickened lateral nerves on both sides of lamellae; epichile 2 mm long, 2.5 mm wide, transversely elliptic in outline, obtuse, margins somewhat erose. Gynostemium 5 mm long, ciliate in the lower part.

Etymology. – An allusion to the form of the rachis.

Ecology. – Terrestrial in forest.

Distribution. – Known from Colombian Chocó only.

Notes. – This species is unique in the genus Palmorchis by its fractiflex rachis. It is somewhat similar to P. pandurata , but its epichile is entire, transversely elliptic, obtuse and lip callus consists of 3 lamellae running from lip base to the apex, being highest in the upper part.

Figures

Fig. 2. – Palmorchis FractiFlexa Szlach. & Baranow. A. Dorsal sepal; B. Lateral sepal; C. Petal; D. Lip. [Bernal & al. 3094, COL] [Drawn by A. Król]