Ceropegia boonjarasii Kidyoo, 2018

Kidyoo, Manit, 2018, A new species of Ceropegia (Asclepiadoideae, Apocynaceae) from eastern Thailand, Phytotaxa 385 (1), pp. 31-36 : 31-32

Ceropegia boonjarasii Kidyoo , spec. nov. ( Figs. 1 & 2a–d )

Ceropegia boonjarasii is distinguished from C. sootepensis by its glabrous leaves (vs. leaf being pubescent on the upper surface in C. sootepensis ), a less bulbous corolla tube, corolla lobes that are covered by long purple apically clavate hairs on the distal half (vs. with short simple, white trichomes in C. sootepensis ), and deeply bifid interstaminal corona lobes with linear-lanceolate segments which are abaxially with scattered trichomes (vs. shortly bifid interstaminal corona lobes with glabrous triangular-subulate segments in C. sootepensis )

Type:— THAILAND. Ubon Ratchathani: Pha Taem National Park , near the tourist information center, 230 m, 12 September 2012, M. Kidyoo 1567 (holotype, BKF!; isotype, BCU!) .

Description

Twining herbs. Rootstock tuberous, tubers subglobose to globose, smooth, brown, 1.5–2 cm in diameter. Stem terete, usually unbranched, 0.5–1 m long, internode 3–15 cm long, 1–2 mm in diameter, glabrous, green to greenish brown or reddish brown. Leaves opposite; petiole stout, grooved on the upper surface, 0.5–1 cm long, 1–1.2 mm in diameter, puberulent along the margins of the groove; blade linear or linear-laceolate, 6–14 × 0.3–1 cm, chartaceous to coriaceous, slightly carinate in cross section, apex acute to acuminate, base cuneate, acute to obtuse with 1–2 small ovate colleters, 0.24–0.32 × 0.15–0.26 mm on the adaxial surface, margins entire, slightly revolute, occasionally ciliate; upper surface green, glabrous, lower surface pale green, glabrous; midrib distinct, slightly grooved on the upper surface, prominent on the lower surface; lateral veins 8–10 pairs, indistinct on both surfaces. Inflorescences 1–2-flowered, extra-axillary; peduncle (sub)sessile, up to 3 mm long, 0.8–1 mm in diameter, greenish brown to reddish brown, glabrous; pedicel green, greenish brown to reddish brown, glabrous, 0.5–1 cm long, 0.8–1 mm in diameter; bracteoles minute, subulate to lanceolate, 1–2 mm long, apex acuminate, pale green to greenish brown, glabrous. Calyx lobes free, lobes pale green or reddish brown, lanceolate, 6–7 × 0.7–1 mm, apex acuminate, glabrous. Corolla tubular-infundibuliform, 4–5 cm long, upright, yellowish white to greenish white with reddish brown lines along the tube length; tube 2.7–3.5 cm long, glabrous, inflated at base, 0.6–0.8 cm in diameter, interior of the inflated portion dark purple, tube becoming straight above the inflated portion and then gradually widening upward, mouth of the tube 0.7–0.9 cm in diameter; lobes ovate-lanceolate, 1.1–1.3 × 0.5–0.6 cm, apex obtuse, adaxial surface glabrous, each lobe reduplicate from near the base, tips connate, the inner proximal portion yellowish green, a transverse reddish brown band present at the inner mid-portion, the inner distal portion green with long purple hairs at the margins, 2.5–4 mm long. Gynostegium subsessile, stipe ca. 0.5 mm long, ca. 1 mm in diameter. Corona biserate; interstaminal corona joined to form a shallow cup, 3.1–3.5 mm in diameter, lobes deeply bifid, each segment lanceolate with acute-blunt apex, white to purplish white and covered with sparsely purple hairs; staminal corona lobes terete, linear to slightly ligulate with blunt apex, 2.1–2.3 mm long, 0.3‒0.4 mm in diameter, incumbent on the backs of the anthers, proximal part of lobe purple, distal part of lobe usually long, connivent-erect, slightly recurved, white. Pollinaria : pollinium broadly ovoid, yellow, 0.54–0.6 × 0.3–0.4 mm, germination crest sub-apical; translator arms rectangular, stout, hyaline; corpusculum spathulate, reddish-brown, 0.34– 0.38 × 0.15–0.16 mm. Follicles 2, slightly diverging, linear in outline, 11–13 cm long, 0.5–0.6 cm in diameter. Seeds oblong-elliptic, 6.6–8 × 2.3–5.5 mm; coma 1.5–2 cm long, white.

Figures

FIGURE 1. Illustrations of Ceropegia boonjarasii. A, Flowering branch; B, Tuber; C, Flower; D, Longitudinal section of flower showing corona and gynostegium; E, Side view of gynostegium; F, Top view of gynostegium; G, Calyx; H, Pollinarium; I, Fruit; J, Seed. Drawn by Manit Kidyoo from M. Kidyoo 1567 A–H and M. Kidyoo 1568 I–J.

FIGURE 2. Photographs of Ceropegia boonjarasii (A–D) and C. sootepensis (E–G): A, Habitat; B, E, Flower; C, F, Corolla lobes; D, G, Side view of gynostegium. Photograph by Manit Kidyoo.