Gaylussacia Kunth 2024, Nov. Gen.

2. Gaylussacia Kunth, Nov. Gen. Sp. Pl. 3: 275. 1818. Subshrubs to shrubs, occasionally small trees; branches glabrous or with non-glandular or glandular trichomes, generally with frequent glands on the leaves, especially on the abaxial surface. Leaves more frequently alternate, commonly imbricate; petiole more frequently robust; blades chartaceous to coriaceous, flat or conduplicate, margin flat or slightly to strongly revolute, often with apical glands. Inflorescence in panicle or raceme, axillary or subterminal, bracteate at the base of the inflorescence; bract 1, inconspicuous, bracteoles 2. Bisexual flowers, pentamerous, actinomorphic, diplostemonous, pendulous; calyx conical at the base, not fleshy, short lobes, not accrescent to the fruit; corolla gamopetalous, urceolate, tubular, cylindrical or campanulate, white, pink, or red, lobes straight or recurved; stamens 10, equal among themselves, erect, filaments flattened, anthers bifid, dorsifixed in the lower half, with poricidal dehiscence, truncated thecae, devoid of appendage; ovary inferior, pseudo-10-locular, uniovulate locules, filiform style, and truncated stigma. Fruit type drupoid (nuculanium), with 10 pyrenes; fusiform seeds. Gaylussacia comprises 54 species (Romão et al. 2017) distributed throughout the Americas in three main zones: 1. Eastern North America, from the southern United States to southern Canada; 2. Northern South America, especially in Colombia and Venezuela; and 3. Eastern Brazil, mainly from the states of Bahia to Paraná (Romão 2011). In Brazil, 43 species are identified, of which 42 are exclusive to the country. Recognition of the genus is relatively straightforward, requiring the combination of shrubby habitat and small, showy, campanulate or variations of this flower shape, along with the presence of an inferior ovary with uniovulate locules, and 10 stamens of equal length with straight filaments.