Centronia

Abstract: A historical review, the circumscription problems and nomenclatural changes based upon a phylogenetic morphological analysis of the genus Centronia are presented. In this framework, four Andean species of Centronia are transfered to the genus Meriania (M. brachycera, M. haemantha, M. mutabilis and M. mutisii ) and five new species related to this group ( M. aguaditensis, M. arizae, M. silverstonei, M. sararensis and M. yalconensis ) and three new subspecies of M. haemantha (subsp. chaponensis , subsp. orientalis and subsp. virolinensis ) are described. The selection of lectotypes of M. haemantha and M. mutisii is made and four names Centronia eximia, C. pulchra, C. dichromantha and C. insignis , are considered synonyms. We argue that this group of nine species is a natural group witthin the genus Meriania , and present taxonomic revision.

Abstract: Centronia is a neotropical genus with 15 species that present circumscription problems with other genus of the tribe Merianieae like Meriania and Graffenrieda. To test its monophylie, a cladistic analysis of the genus based on morphological characters was carried out. Fourth five species of 10 genera there were included in the sample; one species of Miconia from tribe Miconieae was the most external group; of Centronia we considered 13 species. A whole of 103 morphological characters was employed. Centronia is a polyphyletic group with 10 species associated to the genus Meriania, one to Wurdastom, 2 of generical uncertain position and 2 species that conform the monophyletic group Centronia "sensu stricto". Centronia s.str. don't has sinapomorphies its characters support also been in Graffenrieda, however the resolution of this analysis is not enough to merge it in Graffenrieda. Here we propose that the Andean group of this genus should be transfer to Meriania.

Abstract: Introduction The genus Conostegia (Miconieae, Melastomataceae) includes shrubs and trees distributed in the Caribbean, Mexico, Central America, N Andes and Brazil (Schnell, 1996). At present, Conostegia contains about 40 species (Schnell, 1996; Mabberley, 1997), although over 100 names have been applied to the genus in the past. However, the elevated number of species has been explained as a probable misinterpretation of the intraspecific variation that occurs in some species (Schnell, 1996). The name Conostegia , which is derived from the Greek words κονοσ = cone and στeγοσ = roof, was chosen by D. Don (1823) for grouping species characterized by flowers having their sepals fused into a cone-shaped calyptra (Fig 9.1 A–D). Despite the fact that a calyptrate calyx is present in other genera of the Melastomataceae, such as Bellucia, Blakea , Centronia , Henriettea , Llewellynia , Miconia and Pternandra (Schnell, 1996; Penneys et al., 2010), the peculiar calyx of Conostegia has long been regarded as a useful character for segregating Conostegia from other non-calyptrate species of Melastomataceae (Don, 1823). Species of Conostegia are immediately recognizable by the character combination of terminal inflorescences, flowers often multistaminate, calyx clearly circumscissily dehiscent at anthesis, anthers isomorphic and unappendaged, ovary inferior and berry fruits (Almeda, 2008).