Published online by Cambridge University Press: 11 May 2009
All the currently known species of Guitarra with spiny isochelae have been reviewed by SEM: Guitarra fimbriata, Guitarra indica, Guitarra bipocillifea, Guitarra abbotti and Guitarra laplani. A new species from Namibia;Guitarra flamenca, is described, which is characterized by bipocilla-like spiny isochelae similar to those of Tetrapocillon atlanticus, placochelae in two different morphological categories and very robust megascleres. After a revision through SEM of the specimen of Guitarra fimbriata var. indica, it clearly belongs to Guitarra flamenca sp. nov. The morphological variability of the placochelae and the spiny isochelae across the Guitarra-species has been analysed and the main parameters useful to differentiate species are highlighted.