Pterichis lunatilabia Kolan., Baranow, S.Nowak & A.Fuentes, 2020

3. Pterichis lunatilabia Kolan., Baranow, S.Nowak & A.Fuentes View in CoL , sp. nov. — Fig. 4 View Fig

The species can easily be distinguished from P. galeata and P. leucoptera by the oblong-lanceolate, sparsely ciliate petals (see notes). — Type: A.F. Fuentes et al. 16211 (holo LPB), Bolivia, La Paz, Prov. Bautista Saavedra, Área Natural de Manejo Integrado Apolobamba, Paján, sector Cochapata, Pajonal en ceja de monte inferior pluvial, alt. 3093 m, 19 Apr. 2010. Paratype: S.G. Beck 1146 (LPB), Bolivia, La Paz, Prov. Murillo, Valle de Zongo, c. 15 km desde la cumbre, alt. 3150 m, 7 Apr. 1979.

Etymology. In reference to the lip shape, which is crescent moon-like in outline – derived from the Latin lūnāris (‘of or pertaining to the moon’).

Plant 18–35 cm tall. Leaf to 28 cm long, less than 1 cm wide, linear-lanceolate, acute. Scape erect, terete, apically glandular-puberulent, with 3 or 4 tubular, acuminate sheaths. Inflorescence racemose, 7–10-flowered, rachis glandular-puberulent. Flowers yellowish or yellowish brown. Floral bracts c. 8 mm long, ovate, acuminate, glandular-puberulent. Pedicellate ovary c. 11 mm long, densely glandular-puberulent. Dorsal sepal 7–8 by 2.5–2.8 mm, ovate, obtuse, externally densely glandular-ciliate, 3-veined. Lateral sepals 7–7.4 by 2.8–4 mm, obliquely ovate or broadly ovate, acuminate or acute, externally densely glandular-puberulent, 3-veined. Petals 8–8.3 by 1.6–1.8 mm, free, oblong-lanceolate, obtuse, sparsely ciliate, 1- or 3-veined. Lip 4.6–5 by 7.5–9 mm, cucullate-concave, base truncate, crescent moon-like in outline; apical lobe oblong-ovate, apiculate, papillose, recurved; disc glandular-ciliate, primarily 7-veined, veins branching, ornamented with numerous rounded glands or knobs along the margin in the upper half. Gynostemium c. 3 mm long.

Distribution — Endemic to Bolivia.

Habitat & Ecology — Terrestrial in very wet areas near paramo yungueño as well as on moss-covered rocks at the altitude of 3090–3150 m. Flowering: April.

Note — This species is similar to P. galeata ( Fig. 5 View Fig ) and P. leucoptera Schltr. ( Fig. 6 View Fig ), but it can be distinguished by the oblong-lanceolate, sparsely ciliate petals (vs glabrous, elliptic above linear claw). Pterichis galeata was the first species described within Pterichis and it is broadly distributed in Andean countries ( Colombia, Ecuador, Venzuela, Peru, Bolivia) and in Costa Rica. The morphological variation of this species prompted Morales (1986) to divide it into two varieties based on the inflorescence (length, number of flowers), but the general flower characteristics, e.g., unguiculate petals and auriculate lip base are consistent between populations. Pterichis leucoptera is a somewhat enigmatic species known from very few collections but according to Schlechter (1921) it differs from P. galeata mainly in the plant size.Also, the lip auricles in P. leucoptera are not conspicuous like in P. galeata and petals are subequal in length to the dorsal sepal (vs petals longer than dorsal sepal in P. galeata ). More Peruvian collections should be made to verify the actual separateness of these two species. In the Bolivian P. mandonii (Rchb.f.) Rolfe (sect. Acraea ), petals are glabrous (vs sparsely ciliate in P. lunatilabia ) and distinctly widened near the middle (vs oblong-lanceolate in P. lunatilabia ). In P. mandonii the broad middle lobe of the lip only slightly exceeds the lip’s lateral lobes (vs much exceeding lateral lobes in P. lunatilabia ).