Vanilla denshikoira Flanagan & Ospina-Calderón, 2018

Flanagan, Nicola S., Ospina-Calderón, Nhora Helena, Agapito, Lucy Teresita García, Mendoza, Misael & Mateus, Hugo Alonso, 2018, A new species of Vanilla (Orchidaceae) from the North West Amazon in Colombia, Phytotaxa 364 (3), pp. 250-258 : 253-255

Vanilla denshikoira Flanagan & Ospina-Calderón sp.nov. ( Figs. 1 , 2 )

Diagnosis:—The new species is similar to Vanilla aspericaulis , V. capixaba , and V. cristagalli , sharing with them a concave lip base, a more or less tri-lobed lip, and a conspicuous tuft of trichomes on the recurved lip apex that is connected to the penicillate callus by a central area of tuberculate papillae and trichomes. The new species may be easily distinguished by the external longitudinal canal running from the lip base to the apex of the reflexed midlobe, and the papillae and elongated trichomes on the ventral lip surface covering the tuberculous keel and central veins from the base to the penicillate callus.

Type:— COLOMBIA. Guainía. Inírida, Resguardo Indígena Remanso-Chorrobocón, medium-dense riparian forest on alluvial ground c. 30m from the Inírida River, Elev. 100 m, 16 April 2017, N. S.Flanagan, M.Mendoza, L. T.García Agapito, H. A.Mateus NSF138 (holotype: CUVC!)

Paratypes:— COLOMBIA. Guainía. Inírida, Resguardo Indígena Remanso-Chorrobocón, medium-dense riparian forest on granite outcrop. Elev. 265 m, 15 April 2017, N. S.Flanagan, M.Mendoza, L. T.García Agapito, H. A.Mateus NSF90 (paratype: CUVC!).

Hemi-epiphyte, elongated, scandent vine, more than 5 m long, with attaching aerial roots. Stem cylindrical, fleshy, glabrous, flexuous, sulcate, dark green, internodes 8–14 cm. Leaves alternate, sub-oblanceolate, obtuse base, apex cuspidate, shorter than internode, 9.6–10.4 long × 2.5–4.5 cm wide; petiole conspicuous, partially-sheathing, caniculate, 0.5–0.7 mm long. Inflorescence axillar, racemose, 2 flowers at anthesis simultaneously, ephemeral, ca. 16 flowers opening in succession. Bracts sheathing, triangular, 6–10 mm wide at base × 4–5 mm long. Flowers conspicuous, pedicellate, sepals and petals greenish-cream on inner and outer, segments spreading, labellum creamy yellow. Ovary 42.5–50 mm long, whitish-cream at the base turning to green in the apical quartile. Dorsal sepal 53.7–58.7 × 10–16.3 mm, obovate, concave, apex obtuse, 12 veins. Lateral sepals 46.5–56.5 × 12.5–16.5 mm, obovate, slightly concave, asymmetric, apex obtuse, 17 veins. Petals 50–50.6 × 13.5–17 mm, obovate, concave, apex obtuse, asymmetric, central longitudinal keel on outer surface, 13 veins. Lip tubular, 41.4–45.9 mm long, concave, fused to column from base to 22.5–24.2 mm, unguiculate, margin ondulated, trilobed. Lateral lobes 12.4–13.5 mm, caliptriform in the apical zone, margins undulate. Midlobe 13.5–15.5 mm long × 9.2–11.9 wide, bi-lobed, conspicuously reflexed. Lip distinguished by a central longitudinal canal on the outer surface, running from the base of the labellum to the apex of the reflexed midlobe, forming a tuberculous keel on the ventral surface, papillae and elongated trichomes (3.2–4.6 mm) covering keel and central veins, dense at base, continuous towards penicillate callus, at 25 mm from the base, 5 transverse imbricate and denticulate scales (2.5–3.5 mm wide × 3.8–4.4 mm high), connecting with tuberculate papillae and trichomes to enlarged tuft of long (5–6 mm), dense, tuberculated trichomes covering most of apical surface. Column 3.2–3.4 mm × 29–29.5 mm long, apex with vertical truncate and ondulate wings, ventral surface presents trichomes in the apical quarter, bi-lobed stigma. Rostellum prominent. Anther versatile, transversely ellipsoid.

Etymology:—The epithet refers to the name of a female figure in the mythology of the Puinave indigenous community, native to the department of Guainía, Colombia. The name ´Denshikoira´ translates in English to “perfumed woman”. Denshikoira, also known as the Princess Inírida, occupies a central position in Puinave culture, with her myth representing the freedom and equality of women. The name was chosen by Lucy Teresita García Agapito, a member of the Puinave Indigenous community of Remanso-Chorrobocón.

Distribution and habitat:— Vanilla densikoira is known only from the two fertile plants in the Type locality, the first close to the River Inírida, in seasonally-flooded, medium-height (between 10–20 m), open (<60% canopy cover) forest at 100 m elevation, and the second also in medium-height, open forest on an igneous outcrop, at 265 m elevation. The floristic composition of these sites is notable for the presence of the following tree species: Clusia columnaris Engler in Martius (1888: 432), Casearia javitensis Kunth in Humboldt, von Bonpland & Kunth (1821: 366), Tapirira guianensis Aublet (1775: 188) , and Chrysophyllum bombycinum Penn (1990: 588) .

Conservation status:— Vanilla denshikoira has an apparent highly restricted distribution, apparent rarity, and both known individuals are highly vulnerable to human activities. Based on the IUCN criteria the species is categorized as Critically Endangered-CR: A3c; B1ab (i,ii,iii,iv).

Figures

FIGURE 1. Vanilla denshikoira Flanagan & Ospina-Calderón. Clockwise from top left, A. Inflorescence B. Plant habit C. Flower D. Labellum. E. Tuft of tuberculate trichomes on the labellum apical surface F. Transversal view of central canal and a tuberculous keel running from the base to the apex of the labellum. (Illustration by Nhora Helena Ospina-Calderón).

FIGURE 2. Vanilla denshikoira Flanagan & Ospina-Calderón in the field. A. Vegetation physiognomy of plant habitat. B. Vegetative habit of plant. C. Inflorescence of the Vanilla denshikoira with two flowers open simultaneously. D. The whole flower showing the longitudinal keel on outer petal surface, and the concave lip. E. Detail of the lip apex of the Vanilla denshikoira showing the caliptriform nature of the lateral lobes with ondulate margins in the apical zone, and the conspicuously reflexed midlobe apex with an enlarged tuft of tuberculated trichomes covering most of apical surface. (Photographs by Nicola Flanagan).