Systematics of Lobelioideae (Campanulaceae): review, phylogenetic and biogeographic analyses

By

Paul, Kagame
Gichira, Andrew
Chen, Lingyun
Wang, Qingfeng.

Type

Article

Date of Publication

2021

Original Publication

PhytoKeys

Volume

174

Pages

13--45

Subjects

Lobelioideae , monophyletic , polyphyletic

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers [2010]-

Identifiers

DOI: https://doi.org/10.3897/phytokeys.174.59555

 

Abstract

Lobelioideae, the largest subfamily within Campanulaceae, includes 33 genera and approximately1200 species. It is characterized by resupinate flowers with zygomorphic corollas and connate anthers and is widely distributed across the world. The systematics of Lobelioideae has been quite challenging over the years, with different scholars postulating varying theories. To outline major progress and highlight the existing systematic problems in Lobelioideae, we conducted a literature review on this subfamily. Additionally, we conducted phylogenetic and biogeographic analyses for Lobelioideae using plastids and internal transcribed spacer regions. We found that former studies have reached agreement on the southern African origin of Lobelioideae, herbaceous habit and Asian origin of giant lobelioids, the convergent evolution of giant rosette lobelioids, and lastly, the multiple cosmopolitan and independent radiation of lobelioids in Africa, Pacific Basin, and the Hawaiian Islands. Also, Apetahia Baill., Sclerotheca A.DC., and Cyanea Gaudich. are paraphyletic, while Lobelia L., Pratia Gaudich., Centropogon C.Presl, Siphocampylus Pohl, and Isotoma Lindl. are polyphyletic. The taxonomy of these genera, especially Lobelia, is particularly quite frustrating. This calls for further reappraisals using both morphological and molecular data.