Original paper
A review of some species of Berkella and Frustulia occurring in freshwaters of Britain and Ireland with documentation of the types of Berkella linearis, B. alpina, Frustulia saxonica and F. crassinervia
Jüttner, Ingrid; Vijver, Bart Van de; Williams, David M.; Cox, Eileen J.; Wetzel, Carlos E.
Nova Hedwigia Band 117 Heft 1-4 (2023), p. 319 - 350
46 references
published: Dec 12, 2023
published online: Nov 14, 2023
manuscript accepted: Oct 12, 2023
final revised version received: Oct 12, 2023
manuscript revision requested: Oct 5, 2023
manuscript received: Aug 11, 2023
DOI: 10.1127/nova_hedwigia/2023/0902
ArtNo. ESP050011700018, Price: 29.00 €
Abstract
In memory of our friend and colleague Luc Ector (1962–2022) and my husband Alan Orange (1955–2023) We investigated the type material of Berkella linearis, B. alpina, Frustulia saxonica, and F. crassinervia, and populations of these taxa and of F. vulgaris, F. quadrisinuata, F. erifuga, and F. amphipleuroides from Scotland and Wales with light and scanning electron microscopy. The species are distinguished from each other in light microscopy by differences in the shape of the valves, apices and central areas, and in scanning electron microscopy by differences in the raphe endings, striation and areola occlusions. Raphe curvature and the shape of the raphe endings vary within species currently in Frustulia and on this basis B. linearis might belong to Frustulia. However, a recent molecular analysis showed that several Frustulia taxa formed a separate lineage and further analysis is required to study relationships of species currently within Frustulia and whether some might belong to Berkella.
Keywords
Berkella • Frustulia • morphology • type specimens