Phenotypic Variation of Wittrockia cyathiformis (Bromeliaceae) Across Life Forms and Forest Types in the Atlantic Rainforest

Background and aims – This study investigates the phenotypic plasticity of Wittrockia cyathiformis (Bromeliaceae), an endemic species of the Atlantic Rainforest, with the aim of evaluating its morphological variation in relation to different life forms and forest types, specifically Dense Ombrophilous Forest and Mixed Ombrophilous Forest.

Material and methods – Field collections were conducted in State Conservation Units and Campos Gerais National Park in Paraná during 2022 and 2023. We measured vegetative morphometric parameters of six to eight bromeliads for each life form (epiphytic, rupicolous, and terrestrial) in each forest type, totaling 43 specimens, with 22 from Dense Ombrophilous Forest and 21 from Mixed Ombrophilous Forest. Additionally, we assessed the regional conservation status of the species in Paraná.

Key results – The life forms of the plant did not result in significant phenotypic variations, except for the length of the leaf sheath, which was greater in epiphytes. However, W. cyathiformis exhibits distinct phenotypic patterns according to forest types, influenced by specific bioclimatic and environmental conditions. Bromeliads in Dense Ombrophilous Forest display characteristics typical of species in warm and humid environments, while in Mixed Ombrophilous Forest, the leaves are narrower with smaller spines.

Conclusion – The different life forms of this bromeliad do not lead to significant morphometric changes; however, phenotypic plasticity is observed among forest types, which may aid the species in adapting to varying environmental conditions. Although W. cyathiformis is classified as Least Concern (LC) in its regional conservation status due to its wide distribution, ongoing habitat loss and fragmentation in the Atlantic Forest necessitate conservation measures to ensure the long-term survival of its populations, as anthropogenic activities induce changes at a pace that may be incompatible with the species' evolutionary adaptations.