Woody liana to 30 m; ‘combretaceous hairs’ and peltate scales present. Leaves opposite, chartaceous, narrowly oblong-ovate, 7-21 x 3-8.3 cm, apex rather gradually shortly to long acuminate, base broadly cuneate to more or less rounded, hairless or almost so, moderately to rather densely lepidote below, sparsely or very sparsely so above, scales usually whitish; venation eucamptodromous-brochidodromous, as in C. laxum except secondary veins 10-20 pairs; petiole 0.6-2 cm long, glabrous, inconspicuously lepidote. Inflorescence sparsely to extensively branched, rather stout, in opposite pairs in leaf-axils, 3-15 cm long, usually aggregated into terminal panicles up to 33 cm long, at lower nodes in axils of normal leaves (fallen by fruiting), at upper nodes without subtending leaves, sparsely pubescent, inconspicuously lepidote. Flowers unknown. Fruit rather densely lepidote, 4-6.5 x 0.8-1.3 cm, very narrowly oblong-elliptic to oblanceolate in side view, tapering to narrow apex and base, without distinct pseudostipe, squarish in sectionwith thick short lateral ridges (scarcely wings) running the length of fruit. Scales as in C. laxum.
French Guiana present, Guianas present, Guyana present, NE Peru present, Southern America: Brazil North (Amazonas present), extreme S Colombia present
Widely disjunct, in Amazonas in extreme S Colombia and NE Peru, and in Guyana and French Guiana; apart from the type only 3 specimens from the Guianas (GU: 2; FG: 2).
Exell (1953) placed
C. fusiforme in synonymy under C. glabrum DC., but I see nothing to connect these two taxa or to view C. glabrum as other than a synonym of C. laxum. The type of C. fusiforme lacks inflorescences (only detached fruits), but the Fanshawe specimen has pubescent rhachides, contrasting with the glabrous ones of C. glabrum. I have not seen any flowering material that can be linked to C. fusiforme, but such material might well be indistinguishable from C. laxum. The scattered distribution of C. fusiforme might indicate that it is only a very extreme sporadic variant of C. laxum.