Recircumscription of Begonia sect. Baryandra (Begoniaceae): evidence from molecular data

Abstract

BackgroundBegonia sect. Diploclinium is a ‘dust-bin’ section for species retaining pleisiomorphic characters and lacking novel synapomorphic characters used to delimit other Asian sections in Begonia. Part of this large and polymorphous section is transferred to Begonia sect. Baryandra in a move towards a more natural classification for the genus.ResultsPhylogenetic analysis of nuclear ribosomal ITS DNA sequences show a strongly supported monophyletic group containing Philippine and Bornean species previously in Begonia sect. Diploclinium, and the type of Begonia sect. Baryandra, B. oxysperma. This clade forms the basis for the now much-expanded Begonia sect. Baryandra, which as defined here contains 49 species and has its centre of diversity in the Philippines.ConclusionsA natural classification for a much expanded Begonia sect. Baryandra has been provided. This paper highlights the feasibility of moving towards a natural classification of Asian Begonia step by step as information comes to light through building upon previous framework phylogenies with denser sampling.Electronic supplementary materialThe online version of this article (doi:10.1186/1999-3110-54-38) contains supplementary material, which is available to authorized users.

Begonia chingipengii (sect. Baryandra, Begoniaceae), a new species from Luzon Island, Philippines

“…Diploclinium (Lindley ex R. Wight 1852: 9) A. de Candolle (1859: 129) from the Philippine were transferred to sect. Baryandra, based on the analysis of morphological features and molecular data (Rubite 2012;Rubite et al 2013). Among about 50 species in sect.…”

“…Recently Philippine Begonia species are delimited into two sections: Baryandra A. de Candolle (1859: 122) and Petermannia (Klotzsch 1855: 74) A. de Candolle (1859: 128) (Rubite 2012;Rubite et al 2013).…”

Begonia tandangii (Begoniaceae, section Baryandra), a new species from Luzon Island, the Philippines

“…Petermannia (Klotzsch 1855: 74) A. de Candolle (1859, and sect. Platycentrum (Klotzsch 1855: 123) A. de Candolle (1859 (Rubite 2012, Rubite et al 2013. Begonia sect.…”

The Calcarea group of Begonia (Begoniaceae) from Borneo, including four new species from Sarawak

“…The most recent comprehensive sectional classification of the genus is that by Doorenbos et al (1998 Diploclinium (Rubite et al, 2013). Doorenbos et al (1998) doubtfully placed Begonia calcarea in Begonia sect.…”

“…Sectional delimitation within this group needs to be revised. Rubite et al (2013) examined the rhizomatous Malesian Begonia sect. Diploclinium group, which has a centre of diversity in the Philippines, in detail and concluded that they were distinct from continental species of Begonia sect.…”