Friday, February 9, 2018

[Botany • 2018] Vantanea maculicarpa • A New Tree Species (Humiriaceae) from French Guiana


Vantanea maculicarpa  Sabatier & Engel 

in Engel & Sabatier, 2018.  DOI: 10.11646/phytotaxa.338.1.12 

Abstract 
A new species of Humiriaceae, Vantanea maculicarpa, growing in French Guiana terra-firme forest is described and illustrated. This new species is distinguished from all other species of Vantanea by fruits covered by white lenticels, a character so far unknown in this genus. It also presents a pubescent intrastaminal disk, a feature encountered in two other Vantanea species only: it is further distinguished from V. parviflora, the morphologically most similar species, by more stamens and from V. ovicarpa by a much smaller rough endocarp with five valves. A key to the species of French Guiana and the IUCN status Least Concern (LC) are proposed. 

Keywords: Vantanea, Humiriaceae, French Guiana, taxonomy


FIGURE 1. Vantanea maculicarpa A. Flowering branch. B. Flower buds and flowers. C. Medial section of flower (note the pubescent intrastaminal disk).

  (A. Sabatier & Prévost 4911. B–C. Sabatier 5574. D–E. Sabatier 4898).
(photographs A–C by Daniel Sabatier and D–E by Julien Engel). 

Vantanea maculicarpa Sabatier & Engel, sp. nov. 

Diagnosis:— Vantanea maculicarpa is distinguished from all other species of Vantanea by its fruits that are covered by white lenticels, a character so far unknown in this genus as all other species of Vantanea have smooth, slightly pubescent or rarely tuberculous fruit surface (V. tuberculate Ducke (1938: 31, pl.5)). Fruits shape is globose, another distinctive feature of V. maculicarpa, as fruits are mostly ovoid or ellipsoid in this genus. Regarding flowers, V. maculicarpa has a pubescent disk, a feature shared by two other species only, V. parviflora and V. ovicarpa respectively. The new species closely resembles V. parviflora: they share leaves greenish-brown above, with secondary and smaller veins visible on both sides, and petioles thickened at base. V. maculicarpa is distinguished by shorter petiole and obovate blades while V. parviflora has more elliptical blades. Regarding flowers, V. maculicarpa differs from V. parviflora in having more stamens (150–230 against 80–120). Filaments length is also more variable (within a same flower) in V. maculicarpa, while it is more uniform in V. parviflora. The length ratio between the longest and the smallest filament of a same flower is also more variable between flowers in V. maculicarpa. To get an approximate picture, this ratio ranges from about 2 to 5 in V. maculicarpa, while it is ranging around 1.6 and quite homogeneous among flowers in V. parviflora. V. maculicarpa differs from V. ovicarpa in having globose, strongly rugose and smaller endocarp with 5 valves while the latter has large, ovoid, smooth endocarp with 6–7 valves.

Distribution and Ecology:— The new species occurs in French Guiana terra-firme forest. 

Etymology:— The epithet refers to the surface of the fruits covered by numerous white lenticels


Julien Engel and Daniel Sabatier. 2018. Vantanea maculicarpa (Humiriaceae): A New Tree Species from French Guiana. Phytotaxa. 388(1); 130–134. DOI: 10.11646/phytotaxa.338.1.12


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