KEYS TO GENERA IN THE CARIBBEAN [pdf]
(Southern Florida, Bahamas, and other West Indian islands,
except Trinidad and Tobago)
by William R. Anderson and Christiane Anderson
Key to specimens bearing fruits [flowers]
1. Fruits with a soft, fleshy, edible exocarp, indehiscent or, in Malpighia verruculosa, the red pyrenes separating at maturity; subshrubs, shrubs or trees.
2. Leaves bearing glands impressed in abaxial surface of lamina; bracteoles eglandular or some bracteoles bearing large abaxial glands; styles slender to stout, of uniform thickness or widened at apex, the stigmas large; inflorescence axillary, without leaves, elongated or condensed and corymbiform or umbellate.
3. Flowers borne in umbels or corymbs or short, condensed pseudoracemes; bracteoles all eglandular; styles 3, distinct; stipules borne on stem between petioles.
1. Fruits dry, breaking apart into mericarps at maturity; shrubs, trees, or slender to woody vines.
4. Mericarps without slender elongated setae.
5. Mericarps smooth-walled cocci.
6. Styles slender and subulate, tapered to a minute stigma; lamina without glands in surface, usually with a pair of tiny marginal glands near base; exotic, widely cultivated as an ornamental shrub but apparently not becoming naturalized.
7. Mericarp samaroid, with either dorsal or lateral wing(s) well developed.
5. Mericarps winged, the wings rudimentary in some species.
8. Samaras with dorsal wing dominant, the nut bearing on its sides only short winglets or crests or quite smooth.
9. Wing of samara with the adaxial edge thickened, the veins diverging from it toward the thinner abaxial edge.
8. Samaras with lateral wing(s) dominant, the dorsal wing smaller or reduced to a winglet or crest, or absent.
10. Flowers borne in congested pseudoracemes, corymbs, or umbels of 4–many; stigmas internal, the style with a dorsal extension at apex or merely apiculate or truncate.
11. Samara with 1, 2, or 3 lateral wings.
13. Samara with the 2 lateral wings distinct at both base and apex (butterfly-shaped); lamina glands, if present, strictly marginal except often a pair at base against midrib.
12. Samara with 1 continuous lateral wing or 2, 1 on each side; native species.
14. Pedicels raised on a peduncle; stipules very short, triangular, interpetiolar.
15. Both bracteoles eglandular; pedicel much longer than peduncle; petiole eglandular or bearing 2–4 small glands at various heights; Lesser Antilles.
2. Leaves and bracteoles eglandular; styles slender and subulate, the stigmas minute; inflorescence an elongated pseudoraceme terminating a leafy shoot.
3. Flowers borne in elongated pseudoracemes; bracteoles (one or both) often bearing 1 large abaxial gland, sometimes 2; styles 2 or 3, distinct or partly to completely connate and then apparently only 1; stipules borne on base of petiole.
4. Mericarps bearing many slender elongated vascularized setae; Cuba.
6. Styles cylindrical, not tapered distally, the stigma truncate or broadened, sometimes becoming subpeltate or bilobed in anthesis; lamina with glands immersed in abaxial surface, at least at base; native in Cuba; probably introduced in the Lesser Antilles.
7. Mericarp wing reduced to a ± triangular dorsal winglet very short relative to size of nut, the mericarp probably adapted for dispersal by water, not wind.
9. Wing of samara with the abaxial edge thickened, the veins diverging and branching from it toward the thinner adaxial edge.
10. Flowers borne in umbels of 4; stigmas terminal, the style without a dorsal extension at apex; Cuba.
11. Samara with 4 lateral wings, 2 on each side.
12. Samara with 3 lateral wings, 1 larger wing at apex and 2 smaller lateral wings; exotic from Asia escaped from cultivation in Florida.
13. Samara with the lateral wing continuous at least at base, continuous at apex or notched to divided to nut; lamina glands, if present, borne on abaxial surface between midrib and margin.
14. Pedicels sessile; stipules elongated, subulate, borne on petiole between middle and apex; Lesser Antilles.
15. One bracteole of each pair bearing 1 large abaxial gland; pedicel shorter than peduncle or about the same length; petiole eglandular or (often) bearing 2 large protuberant glands on distal half; Jamaica.