Massonia inaequalis (Asparagaceae, Scilloideae), a distinct new species from South Africa

Abstract

Asparagaceae subfamily Scilloideae, tribe Hyacintheae is alternatively regarded as Hyacinthaceae subfam. Hyacinthoideae, a treatment we favour. Additional information on generic circumscriptions in Hyacinthoideae can be found in Martínez-Azorín et al. (2013, 2014a, 2014b), Pinter et al. (2013) and Wetschnig et al. (2014). The genus Massonia Houttuyn (1780: 424) belongs to tribe Massonieae of Hyacinthoideae (Speta 1998a, 1998b, Wetschnig et al. 2002, Pfosser et al. 2003, Manning et al. 2004) and is confined to South Africa and southwestern Namibia. Our studies in Massonia reveal that the taxonomy of the genus, as presented in recent revisions, is not satisfactory and several species concepts have been overlooked and misunderstood (Martínez-Azorín et al. 2013, 2014a, 2014b, 2015a, 2015b, 2017, 2018, Pinter et al. 2013, 2015, Wetschnig et al. 2012, 2014, 2016). Within the framework of a taxonomic revision of Massonia, the study of herbarium vouchers in the main South African herbaria and natural populations, revealed the existence of some populations of Massonia growing in the surroundings of Elands Bay (Western Cape Province of South Africa), that represent an undescribed species based on a distinct combination of morphological features, especially regarding flower morphology which show permanently erect perigone segments at anthesis, being unique in the genus. These plants were first collected by W.F. Barker in August 1966 in fruit near Elands Bay and after cultivating them at Kirstenbosch in the following 2 years, Barker deposited 4 herbarium vouchers including plants in flower and fruit, and also photographs of the plants. Barker left the plants unnamed in the original collection in fruit in August 1966 but later, after seeing flowers in cultivation, she named the plants as "Polyxena? Massonia?" evidencing her doubts on their generic placement in June 1968. Finally she recognized it as a new species as "Massonia? inaequalis Barker ms." in May 1969. However, this name has never been published and this species has remained unnamed ever since. Therefore, a formal description for this species is here presented, accepting the Barker's suggested name and authority, and including complete data on morphology, habitat, biology and distribution.