Plastome-based subgenus-level phylogenetic backbone of hawthorns: insights into the maternal position and taxonomic synopsis of Crataegus shandongensis (Rosaceae, Maleae)

By

Lin, Xiaohua
Xie, Si-Yu
Liu, Guang-Ning
Ma, Daikun
Zou, Fei-Ran
Peng, Wei-Dong
Xu, Chao
Liu, Bing (Botanist)
Zhao, Liang
Liu, Bin-Bin

Type

Article

Date of Publication

2025

Original Publication

PhytoKeys

Volume

252

Pages

87--108

Subjects

chloroplast genome , Crataegus , deep genome skimming , lectotype , taxonomy

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers [2010]-

Identifiers

DOI: https://doi.org/10.3897/phytokeys.252.136506

 

Abstract

The recent recognition of the five-subgenera classification within Crataegus has prompted discussion about the maternal phylogenetic relationships among these subgenera, with inconsistencies in taxon sampling, marker selection, and inference methods contributing to differing interpretations. In this study, we performed deep genome skimming sequencing and assembled 63 whole plastomes, including 58 from Crataegus and five from related genera as the outgroups. We employed multiple phylogenetic inference methods (Maximum Likelihood and Bayesian Inference) to reconstruct an accurate phylogeny. The whole plastome-based, maternally inherited trees consistently supported two major clades within Crataegus: one comprising C. subg. Crataegus and C. subg. Brevispinae, the other encompassing the remaining three subgenera. Within the latter clade, C. subg. Sanguineae and C. subg. Americanae formed a sister group, which together were sister to C. subg. Mespilus. Our analysis also revealed a close maternal relationship between C. shandongensis and C. pinnatifida var. major, suggesting the shared maternal ancestry. Furthermore, we updated the description of C. shandongensis based on extensive specimen examination and designated the lectotype for this species. This comprehensive taxonomic synopsis, supported by both phylogenomic and morphological analyses, provides a robust foundation for future taxonomic and evolutionary studies of the Shandong hawthorn.