# The complete chloroplast genome sequence and phylogenetic analysis of Viola grayi (Violaceae)

## TL;DR

This paper presents the first complete chloroplast genome of Viola grayi and uses it to explore its evolutionary relationships within the Viola genus.

## Contribution

The study provides the first complete chloroplast genome sequence for Viola grayi and clarifies its phylogenetic placement.

## Key findings

- The chloroplast genome of Viola grayi is 158,408 bp in length with typical structural features.
- Phylogenetic analysis shows Viola is monophyletic and places V. grayi closely related to V. grypoceras.
- The genome serves as a valuable resource for future evolutionary and taxonomic studies in Viola.

## Abstract

Viola grayi, a caulescent species in subsection Rostratae, adapted to coastal dunes, with leathery leaves, is here reported with its first sequenced complete chloroplast genome (158,408 bp), comprising a large single-copy (86,662 bp), a small single-copy (17,994 bp), and pair of inverted repeats (26,876 bp each). Phylogenetic analysis of 22 Viola species, based on a 184,817 bp whole-plastome alignment, resolved the genus as monophyletic and placed V. grayi in a clade with V. grypoceras (BP = 100). This plastome provides a valuable genomic resource for future comparative, taxonomic, phylogenetic, and evolutionary studies.