Species relationships and phylogenetic diversity of the African genus Encephalartos Lehm. (Zamiaceae)

Automated ISSR Fingerprinting is a Cost-effective way to assess Genetic Diversity and Taxonomic Differentiation – a Case Study on the Encephalartos eugene-maraisii Species Complex

“…Our analyses provide further support for the taxonomic singularity of E. hirsutus and its exclusion from the E. eugene-maraisii complex, concurring with findings of Rousseau (2012); Stewart et al (2023) and Williamson (2021). Within the E. eugene-maraisii complex, however, although analyses were able to partially distinguish species groups in most cases, it is uncertain whether all species delimitations are justified.…”

“…So-called distinguishing characteristics of some of these E. nubimontanus variants may also be exaggerated or represent morphological extremes of E. nubimontanus. To date, previous molecular studies have been unsuccessful in grouping E. nubimontanus individuals together with conspecifics within the complex [76,87]. Alternatively, these results may reflect the presence of a cryptic lineage within E. nubimontanus, or hybridisation with extinct or extant lineages which generates variation in some populations [108], or hybridisation with E. cupidus, with which it historically co-occurred in habitat.…”

“…Within this pool of variation, there may lie undescribed species, or alternatively, species which require merging. Broad taxonomic and phylogenetic studies on Encephalartos place the E. eugene-maraisii complex into a single clade with li le to no resolution and weak support between the member species [76,86,87]. The morpho-geographical classification of Encephalartos proposed by Vorster (2004) 2020) supported the exclusion of E. hirsutus from the E. eugenemaraisii complex, but provided no further insight into the molecular or taxonomic relationships between members of the complex.…”