Description from Flora of China
Koelreuteria formosana Hayata, Icon. Pl. Formosan. 3: 64. 1913; K. henryi Dummer.
Trees, 15-17 m tall or higher. Branches ridged, pubescent. Leaves bipinnate, with petiole ca. 50 cm; leaflets 5-13; petiolules 2-2.5 cm; blades oblong-ovate, 6-8 × 2.5-3 cm, varied in shape and size, subleathery, abaxially glabrous or only barbate at vein axils, base extremely oblique, margin slightly incurved
serrate or nearly entire below middle, apex long acuminate to caudate. Thyrses terminal, large, ca. 25 cm; branches and pedicels pubescent. Flowers yellow, ca. 5 mm in diam. Sepals 5, oval or ovate-triangular, ciliate. Petals 5, lanceolate or oblong, with 2-lobed, tuberculate toothed scale, claw hairy. Stamens 7 or 8; filaments hairy. Capsules inflated, ellipsoid, 3-ridged, ca. 4 cm; carpels subcordiform, abaxially reticulate veined, adaxially shiny. Seeds black, globose, ca. 5 mm in diam.
Koelreuteria elegans subsp. elegans is distributed in Fiji.