Ancistrocladus grandiflorus
Ancistrocladus grandiflorus in Kew Bull. 55: 878. 2000 sec. Taylor & al. 20051
- Type: Cameroon. SouthwestProv.: near Limbe, Mabeta-Moliwe forest,11 Nov. 1992, M. Cheek & P. Ndumbe 3915 (holotype, K not seen; isotypes BR, MO, SCA, WAG, YA).
Notes
We have been unable to locate reported isotypes of Ancistrocladus grandiflorus at BR, MO, SCA, WAG, and YA. The original description of this spe-cies (Cheek, 2000: 879) indicated somewhat smaller sepals and petals, longer filaments, and shorter styles than were observed in the present study, as indicated by measurements in square brackets in the above species description. In fact, the single flowering collection that we have seen from the type locality (Gereau et al. 5594) also has somewhat smaller sepals than other flowering specimens examined, within the size range reported by Cheek (2000), but the few flowers present appear slightly immature. More significantly, Cheek (2000: 879, Fig. 1) reported the corolla aestivation of A. grandiflorus as contorted, whereas all of the flowering specimens that we have examined have imbricate aestivation; the presence of both convolute and im-bricate corolla aestivation within the same species is otherwise known only in A. congolensis. Juvenile leaves collected from the type locality (Gereau et al. 5595) are very similar to juvenile leaves collected at higher elevations at other localities (e.g. Gereau et al. 5560, Letouzey 14589). This species is notable for the relatively large size of its flowers within the genus. It is also notable for the number of its sepals and petals, which are frequently 4 rather than 5, and its stamens, often 8 rather than 10. This is the first report of 4-merous flowers in Ancistrocladus.
Habitat
In wet, primary and usually old secondary forests of Cameroon,on both sandy and clay soils, at 60-940 m.
Conservation
With an EO of less than 5000 km2 and occurring primarily near the well-protected Korup National Park, near Limbe, and in the Rumpi Hills, Cameroon, this taxon is common, though endemic and potentially threatened outside of these areas: Vulnerable (Blac); based on only four collections from a single forest, Cheek (2000: 879) proposed a status of Critically Endangered (CR Alc+2c, Cl+2a).
Description
Juvenile plants unbranched or sparingly branched saplings to 3 m tall. Juvenile leaves oblanceolate, 48.9-79.0 X 10.8-19.3 cm, L/W 4.1- 4.8, at apex short- to long-acuminate with acumen to 12 mm long, at base attenuate, drying papyraceous to chartaceous, dull or somewhat shiny especially on abaxial surface, somewhat discolorous, dark often greenish brown adaxially, lighter often yellowish brown abaxially; pits dimorphic, as in adult leaves or large pits sometimes more frequent and apparently rilled with wax; midrib plane adax-ially, prominent abaxially, terminating in a gland ca. 0.2 mm long; secondary veins 18 to 25 pairs, brochidodromous, with intramarginal vein 3-5 mm from margin; secondary and tertiary venation adaxially and abaxially prominulous; margin thickened, cartilaginous, pale brown. Adult stems climbing to 25 m high, main stems to 30 cm diam., with bark dark brown, very rough, slash dark red, bearing some scattered leaves and also lateral branchlets to 27 cm long, these each bearing 1 to several hooks and groups of leaves; hooks recurved to spiraling, 12-22 mm diam. Adult leaves drying papyraceous to chartaceous, on both surfaces somewhat shiny, in life somewhat discolorous, dark green above, yel-low-green below, drying discolorous, dark brown above, lighter brown beneath; pits dimorphic, small pits densely and evenly distributed on abaxial surface, frequent throughout but more concentrated near midrib and margins on adaxial surface, large pits 0.1-0.5 mm diam., circular or broadly elliptic, widely scattered and not present on all leaves, when present mostly located near base on both sur-faces; midrib adaxially plane, abaxially prominent, sometimes terminating in a tiny gland; secondary veins prominulous on both surfaces; tertiary veins reticulated, prominulous adaxially, nearly plane to somewhat prominulous abaxially; margins plane to shortly revolute; stem leaves with persistence un-known, obovate, 19.6-26.5 X 4.9-7.7 cm, L/W 3.4-4.0, at apex acutely to obtusely acuminate, at base attenuate; secondary veins 10 to 15 pairs, with intramarginal vein situated 2-4 mm from margin; leaves at branchlet apices with persistence unknown, obovate, 23.1-42.4 X 8.8-12.2 cm, L/W 2.5-3.7, at apex shortly and obtusely acuminate to rounded, at base short- to long-attenuate; secondary veins 9 to 17[to 19, Cheek, 2000] pairs, with intra-marginal vein situated 3-5 mm from margin. Inflo-rescence lax, paniculate, lateral among leaves at apices of branchlets, without hooks or bracteal leaves; peduncle 1.5-4.5 cm long, straight; branched portion corymbiform, [3.5- ]5- 8 X 2-15 cm, dichotomously branched; bracts oblong-ovate, 1.5-2.4 X 1.0-1.6 mm, at apex acute to obtuse, at base obtuse, abaxially initially eglandular then later developing gland covering up to 34 of surface; pedicels 3-7[-8] mm long. Flowers all pedicellate; sepals 4 or 5, oblong to oblong-obovate, rounded and entire to minutely papillate at apex, at base cuneate and shortly decurrent on ovary, green with translucent veins and sometimes tinged red-purple outside, abaxially with 2 to 5 large glands, adaxially with small pits, unequal, the 2 or 3 larger sepals 12.6-14.2 X 5.8-6.2 mm, the 2 smaller sepals [6.5-9.0]9.5-11.3 X [3.0-]4.5-5.0 mm; petals 4 or 5, imbricate [contorted], obovate, yellowish white to pale orange [white with pink margins], [9.0-]9.5- 12.0 X [4.5-]5.2-6.1 mm; stamens 8 or 10 in 2 whorls; filaments stout, the shorter 1.5-2.5 [ca. 4.0] mm long, the longer 2.5-3.3 [ca. 5.0] mm long; anthers 1.1-1.6 mm long; ovary ca. 3/4 inferior, the inferior portion 4^5 mm long, the superior portion ca. 1 mm long; styles 3, [3.0- 3. 5]4. 5-5.0 mm long, stigmas 0.9-1.1 X 0.7-0.8 mm. Fruit not seen.