Sedum keniense Y.D.Zhou, G.W.Hu & Q.F.Wang, 2016

Zhou, Ya-Dong, Hu, Guang-Wan, Yan, Xue, Mwachala, Geoffrey, Gituru, Robert Wahiti & Wang, Qing-Feng, 2016, Sedum keniense (Crassulaceae), a new species from Mt. Kenya, East Africa, Phytotaxa 261 (2), pp. 177-184 : 180-182

Sedum keniense Y.D.Zhou, G.W.Hu & Q.F.Wang , sp. nov. ( Fig. 2B & D ; Fig. 3A–E )

Perennial succulent herb, woody at base; stems and leaves farinose; inflorescences of terminal corymbose cymes, many-flowered; flowers yellow. Nearly always in wet places on cliff faces, rarely on trees.

Type: — Kenya. Meru District, Mt. Kenya, eastern slope, Chogoria Route Waterfall , 00°09’02.17’’S, 37°24’32.80’’E, elevation 3184 m, 25 Jan. 2015, SAJIT 002822 (holotype HIB!; isotypes EA!, PE!). The same locality, 12 Aug. 2016, SAJIT 003998 (paratypes HIB!; EA!; PE!) .

Perennial succulent woody herb ( Fig. 3A ); stems much-branched, up to 50 cm long, covered with white powder ( Fig. 3B ). Leaves sessile, alternate, narrowly oblong, 10–40 × 3–8 mm, apex obtuse to acute, base shortly auriculate-peltate, covered with white powder ( Fig. 3B ). Inflorescences of terminal corymbose cymes, many-flowered, up to 10 cm long ( Fig. 3C ); bracts similar to leaves, but smaller ( Fig. 3D ); pedicels 2–10 mm long. Flowers 5-merous ( Fig. 3E ). Calyx-lobes oblong-lanceolate, 5–7 × 1–2 mm, base united for 1 mm, spurs absent or slightly spurred ( Fig. 3D ). Petals bright yellow, lanceolate, 7–11 × 2–3.5 mm, base united, apex obtuse, slightly reflexed in open flowers ( Fig. 3E ). Stamens 10, with antisepalous filaments 3–5.5 mm long; antipetalous filaments inserted 1.3–2 mm above the base of the petals and free for 2–4.5 mm; anthers oval, 0.8–1 mm long ( Fig. 3E ). Nectary scales ca. 0.6–0.8 × 0.6–0.9 mm, shallowlly 2–lobed at the tip. Carpels 5, shortly united at the base, 2–4 × 0.8–1.5 mm; styles ca. 1 mm long ( Fig. 3E ). Seeds numerous, brown to black, oblong to narrowly oblong, 0.5–0.7 mm long ( Fig. 2B & D ).

Etymology: —The specific epithet “ keniense ” is from the name of the country, “ Kenya ”. It also could be interpreted as derived from the name of Mt. Kenya.

Distribution and ecology: — Sedum keniense is only known from Chogoria Waterfall, Mt. Kenya, at an elevation of ca. 3184 m ( Fig. 4 ). The species grows luxuriantly in wet places on the cliff wall close to the waterfall ( Fig. 4C ) and occasionally on trees ( Fig. 4D ).

Figures

FIGURE 2. Micromorphological features of seeds of Sedum ruwenzoriense, S. keniense and S. meyeri-johannis. A. Seed of S. ruwenzoriense; B. seed of the S. keniense; C. testa ornamentation of S. ruwenzoriense; D. testa ornamentation of S. keniense. E. seeds and testa ornamentation of S. meyeri-johannis (without scale, from ‘t Hart & Koek-Noorman 1989). Vouchers:A & C = Mabberley & McCall 304 (EA), B & D = SAJIT 002822 (HIB), E = ‘t Hart 15515 (ZSS).

FIGURE 3. Sedum keniense. A.Habitus; B. stem and leaves; C. inflorescences; D. bracts, sepals and flower buds; E. flower. Voucher: SAJIT 002822 (HIB). Photographs: Y.D. Zhou.

FIGURE 4. A. Map of Kenya, showing the location of Mt. Kenya; B. Satellite imagery of Mt. Kenya, the black dot showing the location of Sedum keniense; C. S. keniense growing in wet places on the cliff face; D. S. keniense growing epiphytically on a tree. Photographs: G.W.Hu (C, D).