Chromosome numbers and the systematics of tribe Vochysieae (Vochysiaceae)

Abstract

With fi ve neotropical genera and ca. 220 species, Vochysieae is the largest tribe of Vochysiaceae, comprising more than 90 % of its species. Preliminary phylogenetic analyses with matK sequence data indicated that Vochysieae may be paraphyletic, separated into the clades QRC (Qualea, Ruizterania and Callisthene) and VS (Vochysia, Salvertia). Whether the genera and the infrageneric taxa are artifi cial is still controversial. In this study, we analyzed the distribution of chromosome numbers in mitotic or meiotic cells among 20 species belonging to the genera Callisthene, Qualea, Salvertia, and Vochysia, that are native and common in Central and Southeast Brazilian forests or savannas. Species of Callisthene and Qualea possessed 2n = 22, while species of Salvertia and Vochysia had 2n = 24 (or n = 12). Th ese chromosome numbers corroborate the recognition of two groups, and also suggest that chromosome evolution based on numerical variation is conservative in these lineages.

IAPT chromosome data 40

“…The present study confirms the results found by previous authors, indicating that the chromosome numbers are stable in Qualea and Vochysia species, and suggests that the chromosome evolution in terms of numeric variation is conserved in these genera, as previously stated by Yamagishi- Costa & al. (2018).…”

“…Pioneering works on chromosome numbers in Vochysiaceae include Goldblatt (1979, Vochysia lomatophylla Standl., 2n = 22), Berry (1987, Vochysia venezuelana Stafleu, 2n = 24), and Barbosa (1999, Vochysia cinnamomea and Vochysia tucanorum Mart., 2n = 24). While the most recent study was conducted by Yamagishi- Costa & al. (2018), including samples of the genera Callisthene, Qualea, Salvertia and Vochysia, from Goiás, Mato Grosso, Minas Gerais and São Paulo states, resulting in 2n = 22 and n = 11 for Callisthene and Qualea, and 2n = 24 and n = 12 for Salvertia and Vochysia.…”