Turnera

Herbs, subshrubs, or shrubs [trees], hairs glandular and simple [stellate], glandular hairs sessile-capitate or microcapitate. Leaves petiolate or sessile, often with nectaries; stipules present or absent. Inflorescences axillary; peduncle free or adnate to petiole (flowers epiphyllous); prophylls persistent. Pedicels absent. Flowers mostly distylous; sepals at least 1/3 connate; petals yellow or white [salmon, pink, orange, or red], sometimes with dark basal spot; corona absent; filaments often with nectaries; anthers dorsifixed or basifixed. Capsules granulose, rugose, or verrucose [smooth]. Seeds reticulate [striate]. x = 5, 7, (13).

Distribution

sc, se United States, Mexico, West Indies, Central America, South America, Africa.

Discussion

Species 142 (3 in the flora).

I. Urban (1883) divided Turnera into nine series, and M. M. Arbo (2008) added two. Phylogenetic studies (S. Truyens et al. 2005; Arbo and S. M. Espert 2009) indicate that it is monophyletic.

Turnera subulata Smith, with a dark basal spot in the yellow petals, has been collected twice, probably as a garden escape, in Miami-Dade County, southern Florida.

Selected References

Arbo, M. M. 2000. Estudios sistemáticos en Turnera (Turneraceae). II. Series Annulares, Capitatae, Microphyllae y Papilliferae. Bonplandia (Corrientes) 10: 1–82.

Arbo, M. M. 2005. Estudios sistemáticos en Turnera (Turneraceae). III. Series Anomalae y Turnera. Bonplandia (Corrientes) 14: 115–318.

Arbo, M. M. 2008. Estudios sistemáticos en Turnera (Turneraceae). IV. Series Leiocarpae, Conciliatae y Sessilifoliae. Bonplandia (Corrientes) 17: 107–334.

Arbo, M. M. and S. M. Espert. 2009. Morphology, phylogeny and biogeography of Turnera L. (Turneraceae). Taxon 58: 457–467.

Arbo, M. M. and S. M. Mazza. 2011. The major diversity centre for neotropical Turneraceae. Syst. Biodivers. 9: 203–210.

Truyens, S., M. M. Arbo, and J. S. Shore. 2005. Phylogenetic relationships, chromosome and breeding system evolution in Turnera (Turneraceae): Inferences from ITS sequence data. Amer. J. Bot. 92: 1749–1758.

Lower Taxa

Turnera coerulea, Turnera diffusa, Turnera ulmifolia

Key

1	Leaves: petiole without nectaries, blade margins revolute; inflorescences 0.5–0.8 cm, not epiphyllous; filaments adnate for 0.2 mm to base of floral tube, anther pockets absent; anthers dorsifixed.	Turnera diffusa
1	Leaves: petiole with nectaries, blade margins not revolute; inflorescences 2–4 cm, epiphyllous; proximal part of filaments adnate by margins to floral tube forming 5 nectar pockets; anthers basifixed	> 2
2	Flowers distylous; petals white.	Turnera coerulea
2	Flowers homostylous; petals yellow.	Turnera ulmifolia