Ctenolophon

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Ctenolophon

Description

Trees. Hairs stellately tufted and simple. Leaves entire, opposite, petiolate, simple, pinnately nerved. Stipules interpetiolar, caducous. Inflorescence an axillary or terminal cymoid panicle. Flowers bisexual, 5-merous, actinomorphic, hypogynous. Sepals basally shortly connate, quincuncially imbricate, subequal, indurate, swollen and persistent in fruit, with stellate hair tufts. Petals free, contorted, caducous, often shortly clawed. Stamens 10, free, inserted halfway the disk, alternately longer and shorter, the longer epipetalous and the shorter episepalous; Ovary superior, 2-celled; Fruit a 1-celled capsule, the woody pericarp finally lengthwise splitting into 2 valves. Seed 1, persisting after falling of pericarp and pendulous from the top of a filiform columella;

Distribution

Africa:, Angola (Angola present); Gabon (Gabon present); Nigeria (Nigeria present); Zaire (Zaire present) Asia-Tropical:, Jawa (Jawa absent); Lesser Sunda Is. absent; Maluku (Maluku); Sulawesi (Sulawesi) West Africa: present
Two species, one (C engleriana MILDBR.) in West Africa (Angola, Zaire, Nigeria, Gabon) and one throughout Malesia (but not in Java and Lesser Sunda Islands and not yet reported from Celebes and Moluccas, where it is expected to occur). For Malesia see .

Anatomy

Ctenolophon has glabrous leaves, but the young shoots and floral parts have tufted, stellate hairs. Stomata are anisocytic to anomocytic. Crystals are mainly solitary and rhomboidal, more rarely clusters intergrading with druses. Crystalliferous bundle sheath cells have unilateral sclerified thickenings (cristarque cells). The petiole and midrib have a simple collateral vascular strand.

The wood of Ctenolophon is characterized by solitary vessels with scalariform perforations, fibres with distinctly bordered pits, parenchyma which is scanty paratracheal and diffuse-in-aggregates, and heterocellular 1-3-seriate rays.

The above attributes are not very helpful in determining the phylogenetic affinity of this monogeneric family Ctenolophonaceae. Its stomatal type removes it from the Linaceae complex, but other leaf anatomical characters are of common occurrence throughout the dicotyledons, including the Linaceae. The wood anatomy of Ctenolophon is very plesiomorphic and cannot therefore be used to support or reject various suggestions of natural affinity of the genus, although similarities with Humiriaceae have been pointed out by HEIMSCH & TSCHABOLD (1972) and METCALFE & CHALK (1950).
— P. BAAS.

Notes

1. The African species C. englerianus MILDBR. is hardly different from the Malesian species, C. parvifolius. The only differences observed are the simple cymose panicle and the stamens being up to 15 mm long in C. englerianus, versus the compound cymose panicle and the stamens up to 10 mm in C. parvifolius.
2. The fruit and seed structure was wrongly described by HUTCHSINSON and by HUB.WINKLER, who said that the seed dangles from a long funicle. The so-called funicle, however, is a filiform columella on which the seed is attached apically.

Citation

BULLOCK - in Kew Bull. 1960: 41
HUB.WINKLER - in E. & P., Nat. Pfl. Fam., ed. 2, 19a. 1931: 122
VAN HOOREN & NOOTEBOOM - in Blumea. 1984: 547