Calliandra

Key to the three new species and morphologically closest species in section Monticola

1. Subshrub prostrate to decumbent ........................................................................................................................................... 2

1’. Shrubs erect, 1.5 to 3.5 m high............................................................................................................................................... 3

2. Leaves with 4–8 pairs of leaflets per pinna, leaflets 10–25 × 5–15 mm, filaments bright pink ...................... C. semisepulta

2’. Leaves with 15–29 pairs of leaflets per pinna, leaflets 5–8 × 1–2 mm, filaments bicoloured (pink at apex and white at base) ......................................................................................................................................................................... C. bromelioides

3. Stipules large, 10–20 mm long; branches and leaf axes covered with dense velutinous indumentum; tector trichomes yellow .......................................................................................................................................................................................... 4

3’. Stipules significantly smaller, with maximum of 5 mm long and 1 mm wide; branches and leaf axes glabrescent to tomentose; tector trichomes white.................................................................................................................................................... 5

4. Stipules coriaceous, peduncular bracts absent, filaments reddish ............................................................................. C. lewisii

4’. Stipules membranaceous, peduncular bracts present, filaments white ................................................................. C. viscidula

5. Young branches and leaf axes glabrescent to sparsely pilose, without glandular trichomes; older branches glabrous; pinnae 2 pairs, 17–21 pairs of leaflets ............................................................................................................................ C. oroboensis

5’. Branches and leaf axes pilose to tomentose with glandular trichomes; pinnae 3–6 pairs, 24–35 pairs of leaflets .. C. elegans