Artabotrys angustipetalus (Annonaceae), a new species from Thailand, including a plastid phylogeny and character evolutionary analyses of thorn occurrence in Artabotrys

Artabotrys R. Br. is one of the larger genera Annonaceae with over 100 species distributed throughout palaeotropics plus northern Australia. Although genus morphologically very well circumscribed, delimitation quite problematic owing to overlapping morphological characteristics. In Thailand, 20 have been reported, including A. multiflorus C. E. Fisch. Detailed comparisons type specimen from Myanmar revealed that occurring in Kanchanaburi Province Thailand represents a new herein described as angustipetalus Photikwan & Chaowasku. The differs by having fewer flowers per hook, linear (vs oblong oblong-lanceolate) petals, acute obtuse) petal apex, longer and narrower petals carpels flower. A multi-locus plastid phylogeny an accession 30 accessions other has reconstructed. results uncover well-supported clade consisting thorn-bearing Artabotrys, recovered outside this clade. To understand evolution thorns ancestral character-state reconstructions were carried out; trait inferred evolved only once Artabotrys. benefits are discussed hypothesized.Citation: E., Damthongdee A., Jongsook H. Chaowasku T. 2021: (Annonaceae), character evolutionary analyses thorn occurrence – Willdenowia 51: 69–82.Version record first published online on 23 March 2021 ahead inclusion April issue.