Saturday, January 2, 2021

[Botany • 2020] Tocoyena atlantica (Rubiaceae, Gardenieae) • A New Species of Tocoyena from the Brazilian Atlantic Forest


Tocoyena atlantica  R. Borges & Gaem

in Borges, Gaem & Roque, 2020. 

Abstract
Tocoyena atlantica, a new species endemic to southern Bahia and northern Espírito Santo states, Brazil, is here described and illustrated. The species consists of trees 5−8 m tall; with petioles 2−5 cm long, and leaf blades 7.4−24.5 × 2.5−9.1 cm, elliptic, adaxially glabrous; calyces cup-shaped with triangular lobes; corolla yellow during anthesis, with tube gradually wider towards the mouth; and laterally compressed hypanthia. Based on IUCN criteria, we consider T. atlantica endangered, with three collection localities within the Atlantic Forest domain. An identification key for species of Tocoyena occurring in the Brazilian Atlantic Forest is also provided.

Keywords: Atlantic rainforest, endangered species, Bahia, mussununga, Eudicots


Holotype of Tocoyena atlantica R. Borges & Gaem at RB.

Tocoyena atlantica  R. Borges & Gaem.
A. Habit, with flowering branches; B. Leaves; C. Flower, side view; D. Flower, top view; detail of anthers and style; E. Terminal portion of branch, showing internodes, stipule, and calyx.
(P.H. Gaem & H.T.A. Morais 212). Photos by P. H. Gaem.


Tocoyena atlantica R. Borges & Gaem, sp. nov.

Diagnosis:— Tocoyena atlantica differs from the other species of the genus by the leaves clustered on tip of branches and disposed between reduced internodes (2–3 mm long); with petioles 2–5 cm long; calyx distinctly lobed (vs. minutely lobed or truncate in T. formosa, T. sellowiana and T. bullata); and a corolla green in bud passing to yellow during and after anthesis (vs. most of the species having a greenish-white corolla during anthesis, passing to creamyellow after anthesis). It resembles T. longiflora by the triangular calyx lobes, but differs from it by having a corolla ca. 10 cm long (vs. ca. 30 cm in T. longiflora), dichasial or thyrsiform inflorescences (vs. fasciculate), and a laterally compressed hypantium (vs. not compressed).

 Etymology:— The specific epithet refers to the Atlantic Forest domain, to which the species is endemic. 

 

Rodrigo L. Borges, Paulo Henrique Gaem and Nádia Roque. 2020. A New Species of Tocoyena (Rubiaceae, Gardenieae) from the Brazilian Atlantic Forest.  Phytotaxa. 470(3); 243–248. DOI: 10.11646/phytotaxa.470.3.4