Fig. 1
From: Within-family plasticity of nervous system architecture in Syllidae (Annelida, Errantia)
Phylogenetic relationships and general morphology of Syllidae. a: Summary of the phylogenetic relationships of Syllidae after [46]. Only genera used in this study (bold) are depicted, except for Anguillosyllis, Amblyosyllis and Perkinsyllis, which indicate some of the unresolved relationships in Syllidae. An asterisk indicates that the relationship between these genera is not resolved or at least one of the genera is polyphyletic. Dashed lines indicate that these genera were not included in the phylogenetic analysis by [46]. Yellow - Anoplosyllinae, purple - paraphyletic Eusyllinae, green - Autolytinae, light blue - Exogoninae, red - Syllinae. b: Schemata representing the general morphology of Syllidae exemplified with Syllis tyrrhena (Syllinae) and Prosphaerosyllis marmarae (Exogoninae). Prostomium bears palps, 3 antennae, 2–6 eyes and nuchal organs; achaetous segment without parapodia but with one or two pairs of tentacular cirri; following segments bear parapodia with dorsal and ventral cirri (Autolytinae lack ventral cirri). Digestive tract consists of an eversible pharyngeal tube, the muscular proventricle, ventricle and intestine. The pygidium bears a pair of pygidial cirri and sometimes a median pygidial papilla