A review of the ecology and status of the Kerry Lily Simethis mattiazzii (S. planifolia) Asphodelaceae in Ireland

Abstract

The distribution, habitat and genetic diversity of Irish populations of the Kerry Lily (Simethis mattiazzii) are described. All sites known in 2009, centred around Kenmare Bay in SW Ireland, were sampled. The species occurs in a relatively uniform plant community, classified as 4030 Dry Heath within a low-lying coastal heath complex. A preliminary genetic investigation involving analysis of 21 chloroplast and nuclear gene regions revealed no genetic diversity in the samples examined, suggesting that the species in Ireland comprises a number of meta-populations, within one large, single population confined to the Derrynane area on the Iveragh peninsula in South-west Kerry (v.c.H1) and one on the north of the Beara peninsula, across Kenmare Bay from Derrynane, in West Cork (v.c.H3). A sixth site, at Cahergarriff on the south of the Beara Peninsula has since been discovered. Of the 5,750 flowering plants recorded in 2009, the biggest meta-population, which also had the highest plant density, numbered 2,364, on Abbey Island, near Derrynane. Results from two brief surveys in 2020 indicate that the populations have reduced in extent and size since 2009. The genetic results so far suggest that the species is genetically depauperate in Ireland, such that the Irish populations may in fact be only represented by a single, or narrow, founder genotype and may be the result of a one-off introduction. The potential mode of arrival of the species to Ireland is discussed in relation to trade with continental Europe, where its distribution is greatest in SW France and western Iberia. A follow-up genetic study is required to confirm these results and explore a putative point of origin for the species in Ireland. Conservation issues are addressed in the light of these observations.