Valeriana xenophylloides 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 : 52

3. Valeriana xenophylloides Sklenář & B.Eriksen , sp. nov. — Figures 1 F–G , 2 K–O

Type: ECUADOR. Azuay: Páramo de Patococha , road Gualaceo-Limón, to the south of the military antennas, W78°40’09’’, S03°02’ 02’’, 3400 m, 1 November 2018 (fl), P. Sklenar, Klimes A. 15580 (holotype PRC; isotype QCA-242019) .

Plants forming semi-globose cushions to 30 cm large. Stems terete, woody, 1.5–1.9 mm in diameter near the base, the upper branches 1.6–2.1 mm in diameter including leaves. Leaves numerous, persistent, only the terminal ones green; petiole white to pale brown with violet streaks, flat, appressed, to 3.7 mm long and 0.5 mm broad, ciliate along the margins; lamina erect to spreading, glossy-green, tubercled, flat to semi-terete, to 0.5 mm thick, narrowly ovate, 1.5–1.9 × 0.6–0.9 mm, the apex obtuse, crowned with (4–)6–8(–11) spreading to erect pellucid trichomes to 0.8 mm long. Inflorescences capitoid, 1–3-flowered, (sub)sessile with the peduncles to 0.5 mm long, the outer bracts leaf-like, ovate, 1.4–1.9 × 0.8–1.2 mm, the inner bracts oblong, 1.2–1.7 × 0.5–0.8 mm, both type of bracts ciliate along the margins and with a few pellucid trichomes at the apex. Flowers gynodioecious; calyx vestigial; corolla white, 3-lobed, funnelform, the tube 1.4–1.8 mm long, the lobes spreading, triangular to ovate, obtuse, 0.9–1.3 × 0.7–1 mm; stamens exserted and spreading, the thecae oblong, 0.16–0.24 mm long; pistil with the style exserted to 1.5 mm, 2-parted, the branches to 0.13 mm long. Fruits unknown.

Among the high-elevation species of Valeriana from the tropical Andes, the cushion habit is also present in V. aschersoniana Graebner (1945: 37) from Peru and V. aretioides Kunth (1819: 324) from Ecuador – Colombia ( Weberling & Uhlarz 1977, Eriksen 1989). However, both species have typically 5-lobed corollas, although flowers are occasionally 3–4-lobed in V. aschersoniana ( Weberling & Stützel 2006) and 4-lobed in V. aretioides (Eriksen 1989) , and leaf laminas lack the distinct crown of trichomes at the apex ( Weberling & Uhlarz 1977), which provides the cushions of V. xenophylloides a slightly silvery-white appearance. Moreover, the flowers of V. aretioides are yellow. Confusion with other species of Valeriana is unlikely.

Distribution and habitat:— Valeriana xenophylloides was collected only once in a very humid bamboo-shrub páramo of southern Ecuador. It grew in patches of open vegetation on wet slopes with a rich cover of bryophytes and lichens ( Figure 3C ). Only a few individual cushions were observed but more plants can be expected to occur at higher elevations.

Conservation status: Data deficient (DD); as only a few individuals have been observed from one locality more field work is needed to assess the conservation status according to the IUCN criteria properly ( IUCN 2022).

Phenology: Flowers were collected in November.

Etymology: The habit of Valeriana xenophylloides resembles Xenophyllum humile (Kunth) (1820: 150) Funk (1997: 239), a distinct cushion-forming Asteraceae species which is commonly found in the paramos of Ecuador and the epithet of the new species refers to this resemblance.

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.