Randia, Linnaeus, 1753

Borges, Rodrigo Lopes, Roque, Nádia, Jardim, Jomar Gomes & Salas, Roberto Manuel, 2024, Novelties in Randia L. (Gardenieae, Rubiaceae) from Brazil, Phytotaxa 645 (1), pp. 43-54 : 51-52

Taxonomic Key to Brazilian species of Randia

1. Species with deciduous leaves, retaining only the fruits during the dry season; fruits muricate ............................. Randia muricata

- Species with persistent leaves, occasionally deciduous; fruits with a smooth or wrinkled external surface, occasionally displaying lenticels..............................................................................................................................................................................................2.

2. Climbers, thorns curved; fruit oblong ......................................................................................................................... R. altiscandens

- Shrubs or trees, thorns plane; fruit globose or ovoid.........................................................................................................................3.

3. Floral bud and corolla lobes with an acute or acuminate apex..........................................................................................................4.

- Floral bud with rounded or obtuse apex, corolla lobes mostly rounded apex...................................................................................6.

4. Thorny branches; calyx lobes elliptic, oblong or obovate, pubescent on both faces .......................................................... R. armata

- Branches facultatively armed; calyx lobes linear or narrowly triangular, glabrous, glabrescent, or ciliolate...................................5.

5. Species with restricted occurrence to Amazon; leaf blade broadly ovate 10–26 × 6–14 cm, glabrous, displaying a slightly rusty coloration after drying; male inflorescence bearing up to 4 flowers....................................................................... R. adolphoduckei

- Species with restricted occurrence in the Atlantic Forest; leaf blade elliptic 9–17 × 3–7 cm, pubescent on the veins, displaying a darkened coloration after drying; male inflorescence bearing up to 3 flowers ............................................................. R. sulbahiana

6. Leaf blades abaxially velutinous-tomentose, vestiture more evident on veins, sometimes only veins with velutinous indument...... ...........................................................................................................................................................................................................7.

- Leaf blades abaxially glabrous, pubescent or puberulous, veins with adpressed or patent hairs......................................................8.

7. Leaf blades bullate when fresh, olive green when dry; foliar indument grayish; 5–7 veins on each side; calyx lobes triangular, internally glabrous, externally strigose; corolla 21–28 mm long, externally glabrous ............................................. Randia itatiaiae

- Leaf blades smooth when fresh, frequently blackish when dry, occasionally dark olive-green; foliar indument concolorous; 7–10 secondary veins on each side; calyx lobes variable in shape, even on the same plant, from narrowly ovate, narrowly obovate to linear, densely pubescent or hirsutulous on both faces; corolla 14–21 mm long, externally pubescent....................... Randia claesi

8. Leaf blades 17–24 × 7–11 cm; male inflorescences 3–6 flora (except uniflora in R. hebecarpa ); fruits pendulous ........................... ................................................................................................................................................................................ Randia hondensis

- Leaf blades 2–12(–15) × 1.2–4.1 cm; male inflorescences 6–20 flora; fruits erect ..........................................................................9.

9. Male inflorescence cymose; calyx lobes elliptic to ovate; fruits pedicellate .................................................................... R. calycina

- Male inflorescence fasciculate; calyx lobes linear, triangular to narrowly triangular; fruit sessile ................................................10.

10. Branches ascending, uniformly divergent at a 45° angle; leaves sessile or subsessile, mucronate (mucro 1–2 mm long); male inflorescences uniflora.................................................................................................................................................... R. hebecarpa

- Branches horizontally or ascending, diverging at an angle greater than 45°; leaves petiolate; mostly without a mucro; male inflorescences more than the 6-flora ...............................................................................................................................................11.

11. Leaf blades with abruptly acuminate or frequently caudate apex; stipules shortly aristate; hypanthium and immature fruit lanuginose; calyx lobes linear or linear-elliptic, pubescent or hirsute on both face; corolla hirsute externally, more densely towards the throat........................................................................................................................................................................... R. pubiflora

- Leaf blades acuminate, acute, obtuse, or rounded at the apex; stipule acute; without arista; calyx lobes triangular or narrowly triangular; corolla glabrous, puberulous or minutely pubescent externally ....................................................................................12.

12. Tertiary venation inconspicuous above; corolla 25–34 mm long; fruit 30–50 mm long, pericarp 1.2–3.5 mm thick, with woody consistence when dry.............................................................................................................................................................. R. ferox

- Tertiary venation nitid above; corolla 11–15 mm long; fruit 15–20 mm long, pericarp ca. 1 mm thick, leathery when dry .........13.

13. Leaf blade widely elliptic, apex cuspidate, glabrous on both faces, mostly papery, occasionally subcoriaceous; domatia absent; female flower subsessile; fruit glabrous................................................................................................................................ R. nitida

- Leaf blade elliptic; apex rounded or obtuse, rarely acute, puberulent on the inner surface; subcoriaceous to coriaceous; domatia in tuff of hairs; female flower pedunculate; fruit puberulous........................................................................................ R. venezuelensis