Genetic and morphological insights into the Carpobrotus hybrid complex around the world

NOVOA, ANA; HIRSCH, HEIDI; CASTILLO, MARÍA L.; CANAVAN, SUSAN; GONZÁLEZ, LUÍS; RICHARDSON, DAVID M.; PYZEK, PETR; RODRÍGUEZ, JONATAN; BORGES SILVA, LURDES; BRUNDU, GIUSEPPE; D'ANTONIO, CARLA M.; GUTIÉRREZ, JORGE L.; MATHESE, MEGAN; LEVIN, SAM; SILVA, LUÍS; LE ROUX, JOHANNES J.

NeoBiota

Pensoft

Lugar: Sofia; Año: 2023 vol. 89 p. 135 - 160

1619-0033

The genus Carpobrotus N.E.Br. comprises between 12 and 25 species, most of which are native to SouthAfrica. Some Carpobrotus species are considered among the most damaging invasive species in coastaldune systems worldwide. In their introduced areas, these species represent a serious threat to native species and significantly impact soil conditions and geochemical processes. Despite being well studied, thetaxonomy of Carpobrotus remains problematic, as the genus comprises a complex of species that hybridize easily and are difficult to distinguish from each other. To explore the population genetic structure ofinvasive Carpobrotus species (i.e., C. acinaciformis and C. edulis) across a significant part of their nativeand non-native ranges, we sampled 40 populations across Argentina, Italy, New Zealand, Portugal, SouthAfrica, Spain, and the USA. We developed taxon-specific microsatellite markers using a Next GenerationSequencing approach to analyze the population genetic structure and incidence of hybridization in nativeand non-native regions. We identified three genetically distinct clusters, which are present in both thenative and non-native regions. Based on a set of selected morphological characteristics, we found no clearfeatures to identify taxa morphologically. Our results suggest that the most probable sources of globalintroductions of Carpobrotus species are the Western Cape region of South Africa and the coastline ofCalifornia. We suggest that management actions targeting Carpobrotus invasions globally should focus onpreventing additional introductions from the east coast of South Africa, and on searching for prospectivebiocontrol agents in the Western Cape region of South Africa.