Closely resembling C riparia except for fewer, sometimes proportionately wider lfts, and for inflorescence sometimes pseudoracemose as in C falcata, known mostly (perhaps only) from plants in cultivation, possibly of hybrid origin (C riparia x falcata?). Stipules of C. riparia. Lf-formula i/(3-)4—7; petioles 6-20 mm; pinna-rachises 1.8-4 cm, the longer interfoliolar segments 5-7 mm; lft-pulvinules 0.4—0.6 x 0.7-0.9 mm, deeply wrinkled; lfts scarcely accrescent distally, the blades narrowly oblong-elliptic from broadly semicordate base, at apex either deltately acute or obtuse apiculate, the penultimate pair 20-27 x 5-9 mm, 3-4.4 times as long as wide; venation of C. riparia. Peduncles when axillary to primary lvs ±1.5-3.5 cm, when terminally racemose (as in C. falcata) much shorter; capitula ±11—22-fld, the sessile glabrous fls homomorphic as to perianth but the androecial tube of one or more (sub)terminal fls longer and more dilated at orifice, the calyx striate, the corolla scarcely so; calyx 2-2.5 x 1-1.5 mm, the teeth 0.3-0.4 mm; corolla 7.2-8.2 mm, the lobes 1.4—2 mm; androecium of peripheral fls 20-24-merous, 3.2-3.6 cm, the pallid tube either included or far exserted 6.5-17 mm, the tassel pink-carmine; ovary glabrous; no nectarial disc seen. Pod and seed unknown.

In parks and gardens, and on roadsides, 950-1500 m, known only from inter-Andean valleys of n.-centr. Colombia: in urban cultivation in Antioquia and Tolima and from the old Guaduas-Honda road in Cun- dinamarca. — Fl. IX—III(—?). — Carbonero de pluma.

Calliandra medellinensis is an ambiguous taxon, not certainly known outside cultivation. In general aspect and in most macromorphic details the plants resemble C. riparia, but have fewer leaflets that tend to be proportionately wider. Of the four known collections, three (including the type) have capitula axillary to primary leaves, but one (Soejarto 3379, NY) has the terminal, pseudoracemose inflorescence of C. falcata, which differs, however, in much wider leaflets. Both C. riparia and C. falcata are commonly planted far beyond their natural range of dispersal, and both are recorded from Colombian urban habitats. The character-combinations observed in C. medellinensis are plausible attributes of hybrid C. riparia x C. falcata, but experimental evidence is required to confirm or refute this hypothesis.