Cryptic species in Pagamea coriacea sensu lato (Rubiaceae): evidence from morphology, ecology and reproductive behavior in a sympatric context

Acta Amazonica

Samantha De Miranda Esteves¹  Alberto Vicentini¹ 

[1] ,Instituto Nacional de Pesquisas da Amazônia Programa de Pós-Graduação em Ecologia Manaus AM ,Brazil

关键词: Population ecology;    species delimitation;    reproductive system variation;    white-sand forests;    Amazonia;    Ecologia de populações;    delimitação de espécies;    variação em sistema reprodutivo;    campinarana;    Amazônia;   

DOI  :  10.1590/S0044-59672013000400003

来源: SciELO

【 摘 要 】

In this study we explore morphological and ecological variation in sympatric populations of Pagamea coriacea s.l. - a species complex from white-sand vegetation in the Amazon. A total of 147 trees were sampled and monitored at three nearby sites in Central Amazon, Brazil. Multivariate analyses of morphology indicated two distinct groups (A and B), which also differed in bark type, each containing subgroups associated with sexual dimorphism. However, a single hermaphroditic individual was observed within group B. As expected, all pistillate plants produced fruits, but 23% of the staminate plants of group B, and 5% of group A also produced fruits. This variation suggests that the sexual systems of both groups are between dioecy and gynodioecy. There was an overlap in flowering phases between the two groups, but the pattern of floral maturation differed. Ecologically, plants of group B were found in more shaded habitats and over sandstone bedrocks, while group A was prevalent in deeper sandy soils as canopy plants. The significances of morphological and environmental differences were tested by a multivariate analysis of variance, and a canonical discriminant analysis assessed the importance of variables. The coexistence in sympatry of two discrete morphological groups in the P. coriacea s.l., with different habitat preferences and reproductive behaviors, indicates they represent distinct species.

【 授权许可】

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