Sericanthe, Robbrecht, 1978

Wursten, Bart, Bridson, Diane, Janssens, Steven B. & Block, Petra De, 2020, A new species of Sericanthe (Coffeeae, Rubiaceae) from Chimanimani Mountains, Mozambique-Zimbabwe border, Phytotaxa 430 (2), pp. 109-118 : 116

Key to the non-coastal Sericanthe taxa from Zimbabwe and Mozambique

This key is adapted from the key for the genus Sericanthe in Flora Zambesiaca ( Bridson 2003) . The character states of taxa other than S. chimanimaniensis were also obtained from Flora Zambesiaca , after verification on a limited number of specimens.

1. Flowering specimens leafless or with only very juvenile leaves present...........................................................................................2

- Flowering specimens with some mature leaves present.....................................................................................................................3

2. Stipular awns 3–5 mm long; calyx ≤ 5.5 mm long; corolla lobes finely pubescent outside; mature fruits orange (in understorey of forest, in forest margins, in deep shade, elev. 480–1035 m) ....................................................................... S. sp. C (Chipinge taxon)

- Stipular awns 0.5–2.5 mm long; calyx 5.5–7 mm long; corolla lobes sericeous outside; mature fruits red (amongst quartzitic boulders or on quartzitic sandy soils, at lower elevations (<500 m) in Brachystegia woodland, at higher elevations in fairly exposed conditions, at (250–) 950–2150 m) ...................................................................................................................... S. chimanimaniensis

3. Leaves membraneous to thinly chartaceous, apex subacuminate to acuminate, mostly apiculate at the very tip; secondary veins 6–7 on each side of midrib; corolla tube subequal to or slightly longer than calyx.............................................. S. sp. A (Nyanga taxon)

- Leaves chartaceous to subcoriaceous, apex rounded, obtuse, acute, subacuminate or acuminate; secondary veins (3–)4–6 on each side of midrib; corolla tube exceeding or subequal to calyx ..............................................................................................................4

4. Leaves narrowly elliptic to elliptic or oblanceolate, with scattered hairs or sometimes just near margins (apart from pubescent midrib and veins) on lower surface, apex subacuminate to acuminate; secondary veins 5–6 on each side of midrib; stipular awns 3–5 mm long; flowers 6–7-merous; corolla lobes finely pubescent outside; calyx ≤ 5.5 mm long; shrub or small tree, 1–3 m tall (in understorey of evergreen forest, in forest margins, in deep shade, at 480–1035 m)................................... S. sp. C (Chipinge taxon)

- Leaves elliptic, broadly elliptic, oblong elliptic or rarely narrowly elliptic, obovate or narrowly obovate, with scattered hairs (apart from pubescent midrib and veins) or softly pubescent on lower surface, apex rounded, acute, subacuminate or acuminate; secondary veins 3–5(–6) on each side of midrib; stipular awns 1–3 mm long; flowers 6–9-merous; corolla lobes sericeous outside; calyx 5.5–12 mm long; shrub or small tree, 1–7 m tall (in dry vegetation types, at 250–2150 m)....................................................5

5. Leaves elliptic to obovate, narrowly elliptic, narrowly obovate or rarely broadly elliptic, 2–7 × 1–3.2 cm; flowers 6–8-merous; calyx 5.5–7 mm long including apiculum 0.5–1 mm long; corolla tube 5.5–9 mm long; corolla lobes 7–9.5 mm long; shrub or small tree, 1–3 m tall (amongst quartzitic boulders or on quartzitic sandy soils, at lower elevations (<500 m) in Brachystegia woodland, at higher elevations in fairly exposed conditions, at (250–) 950–2150 m) .......................................................... S. chimanimaniensis

- Leaves elliptic to obovate, (3–)5–11.5 × (1.5–) 2.5–6.4 cm; flowers 8(–9)-merous; calyx 7–12 mm long including apiculum 1–2 mm long; corolla tube 8–14(–16) mm long; corolla lobes (7–) 8–12 mm long; shrub or small tree, 1–7 m tall (on granite-based soils in Brachystegia woodland, at 800–1800 m)................................................................................................................. S. andongensis