
Pleurothallis cardiothallis
Pleurothallis cardiothallis Rchb.f., Bot. Zeitung (Berlin) 15: 158. 1857.
Type: Ex Anglia in hortum Schillerianum introducta, G.W. Schiller s.n. (holotype, W).
Illustrated specimen: Costa Rica. Cartago: Jiménez, Pejivalle, La Marta, shores of Río Gato, 750 m. 3 Nov 2006. F. Pupulin 6414, R.L. Dressler, R. Gómez, A.P. Karremans & G. Rojas (JBL-spirit; LCDP voucher).
Etymology: From the Greek kardíā, “heart”, and thallós, “stem”, in reference to the heart-shaped leaf.
The large flower up to 35 mm in size opening and closing over three to four days until reaching complete anthesis with strongly reflexed sepals, the peltate lip with the apical margins thickened and folded in, revealing the papillose abaxial surface, distinguish P. cardiothallis from its relatives. The closest species are P. oncoglossa, whose lip ends into a conical, uncinate callus, and P. navisepala, which has much smaller flowers usually produced 2–4 at once. The yellow phase in species which normally have purple flowers is quite common in Pleurothallis, includuing Macrophyllae-Fasciculatae group.