Platystele shanti Karremans. A. Habit. B. Flower 2024, sp. nov.
Creators: name: Karremans, Adam P.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Asparagales
Orchidaceae
Platystele
Platystele shanti

description: Platystele shanti Karremans, sp. nov. (Figures 1a–d and 2a).
Type:— COSTA RICA. Alajuela: San Carlos, Quesada, 3 km al noroeste de San Vicente, subiendo hacia el Cerro Platanar, 10°17’40.21”N 84°22’22.99”O, 1820 m, 30 July 2020, flowered in cultivation 20 January 2021, G. Rojas-Alvarado 429 (holotype: JBL-spirit, B2261).
The general appearance is similar to P. propinqua (Ames 1923: 68) Garay (1968: 233), but with the leaves spathulate (vs. narrowly elliptic-obovate), the inflorescence pendent (vs. horizontal to erect), up to 7 cm long (vs. ca. 1.2 cm), becoming two to three times longer than the leaf (vs. subequal to the leaf), and bearing up to 25 flowers per coflorescence (vs. ca. 5). The flower has recurved (vs. straight) segments, the sepals and petals are glandular papillose in the adaxial surface (vs. glabrous), and sepals have short, blunt tails (vs. sepals acuminate). The sepals are significantly shorter, 3.0– 3.5 mm (vs. 4.7–5.0 mm), and the lip is shorter (2.6–2.8 mm vs. 5 mm) with a blunt apical tail (vs. gradually tapering to an acuminate apex).
Description:— Plant minuscule, epiphytic, caespitose, erect, up to 5 cm tall, including the inflorescence. Roots basal, flexuous, filiform. Ramicauls erect, slender, 1–2 mm, enclosed by tubular, imbricating, slightly compressed, membranous sheaths. Leaf spathulate, erect, conduplicate, subacute, emarginate, abaxially keeled and terminating in a short apiculus, 1.5–3.5 × 0.4–0.6 cm, narrowed at the base into a conspicuous, conduplicate petiole. Inflorescence racemose, distichous, lax, successively flowered, bearing a single coflorescence, each producing up to 25 flowers, a single one open at a time, becoming significantly longer than the leaf, up to 7 cm long, pseudopeduncle 2.0– 2.5 mm long. Floral bracts acute, conduplicate, ca. 1 mm long. Ovary triangular, glandular, ca. 1 mm long, pedicels 2.5–3.0 mm long. Flower with the sepals and petals free, spreading, recurved, the adaxial surface of the blades conspicuously glandular-papillose, yellow more or less suffused with reddish-purple. Dorsal sepal triangular-lanceolate, margin erose-dentate, acute, shortly apiculate, 3.0–3.5 × 1.1–1.4 mm, 1-veined. Lateral sepals subequal to the dorsal sepal, lanceolate, margin glandular, acute, shortly apiculate, 3.0–3.1 × 1.3–1.5 mm, 1-veined. Petals lanceolate, margin glandular, spreading, acute, shortly acuminate, 1-veined, 2.5–3.0 × 0.5–0.6 mm, 1-veined. Lip ovate, glandular, acute, with a blunt, short tail, with a small circular glenion at the base, 2.6–2.8 mm × 1.1–1.2 mm. Column short, subcylindrical, 1 mm long. Anther apical, stigma subapical, transversely bilobed at each side of the anther. Pollinia 2, obovate. Fruits and seeds unknown.
Distribution and ecology:—The plant grows as an epiphyte on exposed, mossy, low branches in primary and secondary forest at elevations between 1820 and 1890 m. It is currently known only from the windy slopes of the Platanar Volcano around the Juan Castro Blanco National Park, close to Ciudad Quesada, where it is locally abundant (Figure 2d–e), and grows together with several other Pleurothallidinae belonging to diverse genera. Plants were registered to flower in January, February, April and August, it is likely that its flowering period can extend year round given the long, successively flowered coflorescences.
Etymology:—The name Shanti comes from Hinduism and is a Sanskrit word that means peace, tranquility.
Additional specimens examined (paratypes):— COSTA RICA. Alajuela: San Carlos, Quesada, volcán Platanar, 10°17’43”N 84°22’18”W, 1890 m, 17 abril 2021, floreció en cultivo el 13 de agosto 2024, A.P. Karremans, I Chinchilla, K. Gil, G. Rojas-Alvarado & A. Serna Sánchez 8680 (JBL-spirit!; Fig. 2c). Idem, flowered in cultivation 8 February 2023, A. P. Karremans et al. 8679 (JBL-spirit, A-0875!). Idem, flowered in cultivation 21 April 2022, A. P. Karremans et al. 8678 (JBL-spirit, B-2437!). Quesada, 3 km al noroeste de San Vicente, subiendo hacia el Cerro Platanar, 10°17’40.21”N 84°22’22.99”O, 1820 m, 17 abril 2021, flowered in cultivation 22 August 2024, G. Rojas-Alvarado, A. P. Karremans, I. Chinchilla, K. Gil & A. Serna Sánchez 465 (JBL-spirit!; Fig. 2b).
Taxonomic discussion:— Platystele shanti has been confused with P. propinqua, but the latter has larger flowers, borne on a few-flowered, erect inflorescence, that are subequal in length to the narrow leaves. The floral segments of P. propinqua are larger, straight and glabrous, and the sepals are acuminate, the lip is large gradually tapering to an acuminate apex.
From Platystele oxyglossa (Schlechter 1912: 354) Garay (1974: 120), P. shanti differs in the larger plants, longer and broader leaves, with longer, pendent inflorescences, bearing more flowers per coflorescence, with the sepals and petals recurved and notoriously glandular (vs. straight and glabrous). The sepals are larger, broader, apiculate (vs. long acuminate), the petals are broader and longer (2.5–3.0 vs. 1.5 mm long), and the lip is broader and longer.
description: Published as part of Karremans, Adam P., 2024, Platystele shanti, a petite novel jewel from Costa Rica, pp. 215-220 in Phytotaxa 672 (2) on pages 216-219, DOI: 10.11646/phytotaxa.672.2.8, http://zenodo.org/record/14520719