Monanthotaxis kenyensis (Verdc.) P.H.Hoekstra, 2021

Hoekstra, P. H., Wieringa, J. J., Maas, P. J. M. & Chatrou, L. W., 2021, Revision of the African species of Monanthotaxis (Annonaceae), Blumea 66 (2), pp. 107-221 : 166-167

39. Monanthotaxis kenyensis (Verdc.) P.H.Hoekstra , comb. nov. & stat. nov. — Map 25

Monanthotaxis parvifolia (Oliv.) Verdc. subsp. kenyensis Verdc., Kew Bull. 25 (1971b) 27. — Type: B. Verdcourt 2620 (holo K000198975 ; iso BR0000008801685 , EA, PRE0396142 -0), Kenya, Central , 14 falls, near where Donyo Subuk Road crosses river Athi, 14 Jan. 1960.

Shrub, scandent shrub or liana, to 5 m tall; young branches sparsely to densely covered with erect, reddish brown hairs 0.2–0.3 mm long, becoming glabrous; old branches grey-black to blackish. Leaves: petiole 4.5–7 mm long, 1–1.5 mm diam, grooved, indument as on branches; lamina oblong-elliptic to narrowly so, 4.5–10.8 by 1.9–4.8 cm, 2–2.9 times longer than wide, chartaceous, not punctate, glaucous below, primary vein yellowish or reddish, often contrasting with darker petiole, above glabrous, below sparsely covered with appressed, yellowish to pale brown hairs 0.2–0.3 mm long, becoming glabrous, base subcordate, with slightly thickened margins, apex obtuse, secondary veins 9–12 per side, curving upwards, tertiary venation reticulate, raised above, not visible below. Inflorescences leaf-opposed or extra-axillary, composed of solitary flowers; sympodial rachis 0–1.5 mm long, densely covered with erect hairs; pedicels 15–18 mm long, c. 0.3 mm diam, fruiting pedicels c. 0.7 mm diam, sparsely covered with ascending to erect, short hairs; lower bracts absent, upper bract in lower half to halfway up the pedicel, ovate to lanceolate, 0.7–1.1 by 0.3–0.4 mm, indument as on pedicel; flower buds globose. Flowers bisexual; sepals connate at the base, depressed ovate, 1.2–1.3 by 1.8–2 mm, apex obtuse, densely covered with appressed, yellowish hairs, persistent in fruit; receptacle c. 2.2 mm diam, flat, covered with brown, short hairs between carpels and stamens; petals yellow, 6, in two whorls, outer petals broadly ovate, 6.1–7 by 5.6–6.7 mm, outside covered with yellowish hairs, inside with hairs at the apex and margins, inner petals elliptic to rhombic, 5.2–5.5 by 2.9–3.8, outside covered with hairs, inside with hairs at the apex; stamens 9–15, in one whorl, free, obconical, 1.1–1.2 mm long, filaments 0.5–0.7 mm long, thecae extrorse, connective truncate, glabrous, staminodes absent; carpels 12–17, subcylindric, 1.3–1.4 by 0.3–0.4 mm, glabrous, ovules 1 or 2 (or 3), basal or lateral, stigma elongate, c. 0.5 mm long, glabrous. M o nocarps 1– 6, orange to red when ripe, narrowly ellipsoid, 13–26 by 5–5.5 mm, glabrous, apex apiculate, apiculum c. 1 mm long, stipes 3–4 mm long, terete to slightly grooved. Seeds 1 or 2, ellipsoid, 7–8 by 4.5–5 mm, ochre-brown, ends slightly apiculate, raphe not visible or slightly visible.

Distribution — Ethiopia, Uganda, Kenya.

Habitat & Ecology — In dry rocky forest, submontane forest, gallery forest, woodland and rocky outcrops on rocky hillsides, river banks.Altitude: 770–1945 m. Flowering: January to June; fruiting: February, April to July, September, November, December.

Preliminary IUCN conservation status — Least concern (LC). EOO: 337 422 km 2, AOO: 76 km 2. There are more than 10 populations of which the majority from forest reserves and the species is locally common.

Note — Monanthotaxis kenyensis was treated by Verdcourt (1971b) as a subspecies of M. parvifolia . Monanthotaxis parvifolia is very variable in leaf shape and indument density, and the leaves of some specimens resemble those of M. kenyensis . The two species are set apart by the number of stamens per flower: 9–15 stamens in a single whorl in M. kenyensis , and 24 stamens in three whorls in M. parvifolia . Monanthotaxis kenyensis shares the single whorl of stamens with M. maputensis and M. caffra , but differs from the latter two species in its longer pedicels and petiole, and subcordate leaf base.

Figures

Map 25 Distribution of Monanthotaxis kenyensis (Verdc.) P.H.Hoekstra (●, O means uncertain det).