Valeriana yacuriensis Sklenář & B.Eriksen, 2023

Persson, Claes, Eriksen, Bente, Pérez, Álvaro J., Zapata, J. Nicolás, Couvreur, Thomas L. P. & Sklenář, Petr, 2023, Three new species of Valeriana (Valerianoideae, Caprifoliaceae) from southern Ecuador, Phytotaxa 579 (1), pp. 47-53 : 49-51

2. Valeriana yacuriensis Sklenář & B.Eriksen , sp. nov. — Figures 1 D–E , 2 F–J

Type: ECUADOR. Loja: Cordillera las Lagunillas (de Sabanilla), paramo de las Lagunas Negras [Parque Nacional Yacurí], S4° 42’ 36’’, W79° 25’ 44’’, 3500 m, 16 June 2009 (fl), P. Sklenar, J. Mackova, & P. Macek 12053 (holotype PRC; isotypes GB-0210434, QCA-188696) .

Shrubs to 40 cm tall, branched stems ascending to erect, terete, to 4.1 mm in diameter. Leaves numerous, wellspaced basally but becoming densely clustered in the upper part of the branches; the petiole persistent, triangular, flat, sheathing, 1.6–1.7 mm broad basally, ca 2.2 mm long, green distally, whitish-brown with violet streaks basally when young, sparsely ciliate along the margins; the lamina spreading, glossy-green, tubercled, glabrous, flat to shallowly canaliculate towards the petiole, grooved adaxially, ca 0.3 mm thick, oblong to obovate, 4.6–6.3 × 1.7–2.1 mm, the apex obtuse, the margin entire, rarely with a few cilia basally. Inflorescence capitoid, 6–20-flowered, sessile, the bracts leaf-like, ovate, 0.8–1.6 x 2.8–3.8 mm, acute. Flowers gynodioecious; calyx vestigial; corolla white, 3-lobed, narrowly funnelform, the tube to 4.2 mm long, the lobes triangular, 1.3–1.7 × 0.9–1.4 mm, spreading and recurved, the apex obtuse; stamens exserted to 2.1 mm, spreading, the thecae 0.35–0.46 mm long; pistil with the style exserted to 2.7 mm, 3-parted, the branches ca 0.15 mm long. Fruits unknown.

Additional specimens examined: ECUADOR. Loja: Parque Nacional Yacurí, around the upper Laguna Negra , W79°25’27”, S04°42’51”, 3325 m, 7 November 2018, Sklenar P., Ptacek J., Klimesova J., Klimes A. 15684 ( PRC, QCA-241671).

Valeriana yacuriensis is distinguished from the other 3-lobed species of Valeriana in Ecuador and northern Peru by the shrubby habit and petiolate leaves which are distinctly clustered apically. Valeriana imbricata Killip (1928: 501) and V. plateadensis are shrubs but have (sub)sessile, closely imbricate leaves which are persistent throughout the stem, whereas V. xenophylloides (described below) is cushion-forming.

Distribution and habitat:— Valeriana yacuriensis was collected twice at the type locality, i.e., in humid paramo grasslands with scattered shrubs around the Laguna Negra in the Parque Nacional Yacurí ( Figure 3B ). Since the locality occurs at the Ecuador-Peruvian border, the occurrence of the species in the latter country is likely.

Conservation status: Data deficient (DD); as Valeriana yacuriensis has only been collected twice from the type locality it is obvious that more field work is needed in order to assess the conservation status according to the IUCN criteria properly ( IUCN 2022).

Phenology: Flowers were observed in July and November which indicates that the population of the species has a very extended (perhaps continuous) period of flowering.

Etymology: The epithet refers to the name of the Parque Nacional Yacurí where the species was found.

Figures

FIGURE 1. A–C. Valeriana plateadensis. D–E. V. yacuriensis. F–G. V. xenophylloides. A, D, F. Habit. B. Close up of branches. C, E, G. Close up of inflorescence, showing 3-merous flowers. Photographs by Álvaro J. Pérez (A, C), Claes Persson (B), Petr Sklenář (D–G).

FIGURE 2. A–E. Valeriana plateadensis. A. Habit. B. Side view of shoot (left), top view with flowers (right). C. Leaves in top view (left) and side view (right). D. Flower and bracts. E. Longitudinal section of ovary with hanging ovule (left) and of flower (right). F–J. V. yacuriensis. F. Habit. G. Side view of shoot (up), top view with flowers (down). H. Leaves in top view. I. Flower and bracts (left), front view of flower (right). J. Longitudinal section of flower. K–O. V. xenophylloides. K. Habit. L. Side view of shoot. M. Leaves in top view (left), side view (right) and the crown of trichomes at the leaf apex (up left). N. Flower and bracts (left), front view of flower (right). O. Longitudinal section of flower. Line drawings by Bobbi Angell.

FIGURE 3. A. Habitat of Valeriana plateadensis at the summit of the Cerro Plateado Biological Reserve. Photograph by Álvaro J. Pérez. B. Habitat of Valeriana yacuriensis at the Lagunas Negras in the Páramo de Jimbura, Yacuri National Park. Photograph by Petr Sklenář. C. Habitat of Valeriana xenophylloides in the Páramo de Patococha. Photograph by Petr Sklenář.