Ceropegia laikipiensis Masinde

P. Siro Masinde. (2004). Two New Ceropegia (Apocynaceae: Asclepiadoideae-Ceropegieae) Species from Kenya. Kew Bulletin, 59(2), 241-245. doi:10.2307/4115856

Type

Kenya, Longopito, c. 0°42'N 37°10'E, 1975, Powys 20 (holotypus K, incl. ale.).

Morphology General Habit

A sparsely branched, succulent, mostly leafless, glabrous twiner to 1 m high

Morphology Roots

Root system not recorded but most likely fusiform

Morphology Stem

Stem succulent, climbing, c. 2.5 mm in diam., grey-green, very minutely ridged with very fine longitudinal lines, glabrous

Morphology Leaves

Leaves sessile, minute, succulent, caducous, only found near growing apex; lamina linear- subulate, 2 x 0.5 - 1 mm wide at base, apex acute, glabrous on both sides, margins entire and glabrous

Morphology Reproductive morphology Inflorescences

Inflorescence subsessile to shortly pedunculate, flowers in umbellate cymes, 1 - 3-flowered, flowers developing successively, one flower open at a time, scent unknown; peduncle perennial, 0 - 4 mm long, c. 1 mm in diam., thickening on fruit set to 1.5 - 2 mm in diam., glabrous, bracts subulate, c. 1 x 0.4 mm at the base, glabrous; pedicels up to 4 mm long, c. 1 mm in diam., glabrous

Morphology Reproductive morphology Flowers Calyx

Sepals linear-subulate, 3 - 4 x 0.5 - 0.7 mm at the base, clasping corolla, glabrous

Morphology Reproductive morphology Flowers Corolla

Corolla 28 - 38 mm long in total; tube 14 - 22 mm long, prominently inflated in basal 1/4 - 1/3, inflation ovoid, 5 - 7 x 4 - 5 mm in diam., abruptly narrowing above inflation to c. 2 mm in diam. into a long ascending cylindrical portion curved through an obtuse angle (c. 120°) in the middle and gradually dilated thereafter towards apex to c. 5 mm in diam. and suddenly slightly narrowing to c. 4 mm in diam. just at the bases of corolla lobes; tube exterior with a light background which may be unspotted or spotted purplish-maroon especially on inflation and in the apical half of tube, inflation with weak longitudinal nerves, glabrous throughout; tube interior with a light coloured background, spotted purplish-maroon and glabrous inside inflation, apex of inflation at the narrowed area with a ± thickened annulus covered with a dense ring of downward- and inward-pointing whitish hairs which gradually reduce and eventually disappear just below the sharp bend in the tube, apical area in throat spotted purplish and covered with sparse whitish hairs; corolla lobes linear from narrowly deltoid bases, not plicate or only hardly so, 14- 17 mm long, c. 2 mm broad at the deltoid bases and narrowing to c. 0.7 mm for most of the length, connate at apices to form a globose cage which is twice to three times as wide as the widest part of tube; adaxially at bases with a dense cover of relatively long (2.5 - 3 mm), thick (c. 0.1 mm) inward-pointing, multicellular, vibratile, purplish-maroon, clavate hairs; rest of lobe glabrous including abaxial side and margins, light coloured for most part

Morphology Reproductive morphology Flowers Corona

Corona distinctly stipitate, c. 3.5 mm high x 2.5 mm in diam., basally cupular, yellowish-cream; outer (interstaminal) lobes triangular, apically deeply bifid with ± parallel teeth, basally forming pouches c. 1 mm deep x c. 0.7 mm wide, margins glabrous or on adaxial side below bases of teeth with few inward-pointing hairs; inner (staminal) lobes cylindrical, connivent-erect or ± free, c. 2.6 x c. 0.15 mm in diam., ± equalling outer lobes or distinctly longer, apices obtuse and very finely papillose

Morphology Reproductive morphology Flowers Pollinarium

Pollinia ovoid, c. 380 x 280 μm, bright yellowish under illumination, with broad, lateral to subapical germination mouths, with distinct cell ornamentation; corpusculum obovate, orange, c. 240 x 100 μm at centre, with moderately broad basal membranes

Morphology Reproductive morphology Flowers Gynoecium Carpels

Carpels glabrous

Morphology Reproductive morphology Fruits

Follicles paired, acutely divergent, 70 - 100 mm long x c. 4 mm at centre, tapering towards bases and apices, drying straw coloured; seed c. 4 x 2 mm, brownish with a c. 0.5 mm wide, paler, corky marginal wing; coma c. 20 mm long, of silky white hairs.

Ecology

Semi-arid open woodland and bushland; altitude, c. 1700 m.

Distribution

Known only from two remote localities in the Laikipia Plateau, Kenya.

Conservation

An apparently rare species that is only known from three collections. IUCN (2001) category: Data Deficient.

Note

Meve & Mangelsdorff (2001) recently included C. powysii D. V. Field in the circumscription of C. arabica H. Huber and, following this classification, C. laikipiensis is closely related to C. arabica H. Huber var. powysii (D. V. Field) Meve & Mangelsdorff. Ceropegia laikipiensis differs from C. arabica sensu lato mainly by the linear corolla lobes that form a spherical cage, the abrupt strong curvature in the middle of the tube that is similar to that in C. botrys K. Schum., the dense ring of thick hairs in the entrance to the tube and the more deeply lobed outer (interstaminal) corona lobes that are also finely ciliate. The distribution of hairs in the interior of the corolla tube and lobes is similar to that in the poorly known C. subaphylla K. Schum. The stems and general appearance of C. laikipiensis is most similar to C. arabica var. powysii in the following characters: green, succulent stems with very fine longitudinal ridges, that are very gentle to the touch; scale-like, sessile or subsessile, linear-subulate leaves that are usually rapidly caducuous; and mostly sessile or occasionally very shortly pedunculate inflorescences. A black & white photograph of this plant was sent to the editor of Asklepios by Phillip Archer and appeared in Asklepios 62: 8 (1994) as an unknown species. There is little doubt that the photograph represents part of the specimens cited here. The general locality of C. laikipiensis was visited by the author a few years ago but only C. variegata Decne. and C. somalensis Chiov. were found in the area. The two species are stem succulent taxa that can withstand extreme dry conditions during the year as well as browsing by livestock and other wild animals. Ceropegia laikipiensis and C. arabica sensu lato inhabit the semi arid parts of eastern Africa; the latter extends to Arabia.

Apocynaceae (part 2), David Goyder, Timothy Harris, Siro Masinde, Ulrich Meve, Johan Venter. Flora of Tropical East Africa, 2012

Morphology General Habit

Twiner to 1 m high, mostly leafless, glabrous.

Morphology General Exudate

Latex unknown.

Morphology Roots

Root system unknown.

Morphology Stem

Stem climbing, sparsely branched, succulent, ± 2.5 mm in diameter, greygreen, minutely ridged with very fine longitudinal lines

Morphology Leaves

Leaves sessile, minute, succulent, caducous, only found near growing apex; lamina subulate, 2 × 0.5–1 mm, acute

Morphology Reproductive morphology Inflorescences

Inflorescence umbellate cymes, 1–3-flowered, flowers developing successively, one flower open at a time, scent unknown; peduncle 0–4 mm long, thickening to 1.5–2 mm in diameter.

Morphology Reproductive morphology Inflorescences Bracts

Bracts subulate, ± 1 × 0.4 mm.

Morphology Reproductive morphology Flowers Pedicel

Pedicels up to 4 mm long

Morphology Reproductive morphology Flowers Calyx

Sepals subulate, 3–4 × 0.5–0.7 mm, clasping corolla

Morphology Reproductive morphology Flowers Corolla

Corolla 28–38 mm long; tube 14–22 mm long, in basal 1/4– 1/3 with ovoid inflation 5–7 × 4–5 mm, then abruptly narrowing into a long ascending cylindrical part ± 2 mm in diameter, curved through ± 120° in the middle and gradually dilating to ± 5 mm in diameter and suddenly narrowing to ± 4 mm in diameter just at bases of corolla lobes; exterior with a light background, unspotted or spotted purplish-maroon especially on inflation and in the apical half of tube, inflation with weak longitudinal veins, glabrous throughout; lobes linear from narrowly deltoid bases, 14–17 × ± 2 mm and narrowing to ± 0.7 mm for most of the length, not plicate or only hardly so, connate at apices to form a globose cage 2–3 times as wide as the tube; adaxially at bases with a dense cover of 2.5–3 mm thick inward-pointing purplish-maroon vibratile clavate hairs; rest of lobe glabrous including abaxial side and margins, light-coloured for most part

Morphology Reproductive morphology Flowers Corona

Corona distinctly stipitate, ± 3.5 × 2.5 mm, basally cupular, yellowish-cream; outer lobes triangular, apically deeply bifid basally forming pouches ± 1 × 0.7 mm; inner lobes connivent-erect or ± free, ± 2.6 × 0.15 mm

Morphology Reproductive morphology Flowers Pollinia

Pollinia ± 0.38 × 0.28 mm; corpusculum ± 0.24 × 0.1 mm at centre

Morphology Reproductive morphology Fruits

Follicles paired, acutely divergent, 70–100 mm long × ± 4 mm at centre, tapering towards bases and apices, drying straw coloured

Morphology Reproductive morphology Seeds

Seed ± 4 × 2 mm, brownish with a ± 0.5 mm wide, paler, corky marginal wing; coma of silky white hairs ± 20 mm long.

Ecology

Semi-arid bushland/woodland; ± 1700 m

Note

The stems and general appearance are very close to C. powysii but the distribution of hairs in the interior of the corolla tube and lobes is similar to that in the poorly known C. subaphylla. The curvature in the middle of the tube is reminiscent of C. botrys K. Schum. or C. tihamana Defl.

Distribution

Range: Not known elsewhere Flora districts: K1 K3