CALAMYZINAE Hartmann-Schröder, 1971

Watson, Charlotte & Faulwetter, Sarah, 2017, Stylet jaws of Chrysopetalidae (Annelida), Journal of Natural History 51 (47 - 48), pp. 2863-2924 : 2897

Subfamily CALAMYZINAE Hartmann-Schröder, 1971

Subfamily diagnosis

Very short to very long bodied. Prostomium a shallow lobe with two digitiform lateral antennae, differentiated from ventral palps or undifferentiated lateral antennae and lateroventral palps; eyes and median antenna absent; nuchal ciliation present or absent. Strongly muscularized pharynx, little proboscidial development, terminal papillae present (free-living species) or absent (symbiont, ectoparasitic species), jaws present or absent, mouth cover absent. Notochaetae present or absent; neurochaetae compound falcigers or simple hooks. Body ciliation present in free-living taxa, absent in symbionts. Lateral organs absent. Camerate noto- and neurochaetae present in free-living species; camerate neurochaetal shafts present in ectoparasitic taxa; cameration largely modified in symbiont taxa. Quadrate pygidium with two anal cirri in free-living taxa; rounded pygidium with no anal cirri in symbiont taxa.

Remarks

Calamyzas was originally described within a separate subfamily of the Syllidae and Shinkai designated a taxon within the family Nautiliniellidae . Both taxa are now considered derived clades within the Chrysopetalidae , based on recent morphological and molecular data ( Aguado et al. 2013).

The above diagnosis is based on Watson et al. (2016) with further information added for this paper. Calamyzinae comprises free-living, gonochoristic taxa associated with feeding on organic-enriched sediments, e.g. Vigtorniella , Boudemos Watson et al., 2016 , Micospina Watson et al., 2016 ; symbiotic, gonochoristic taxa commensal within deep-sea bivalves, e.g. Shinkai ; and a monotypic ectoparasitic taxon, e.g. Calamyzas , attached to the body of Amphicteis Grube, 1850 , an ampharetid polychaete. Both free-living and symbiont groups lack a median antenna. Free-living calamyzins have differentiated lateral antennae, palps in ventral position and ciliated patches on prostomium and body segments. Symbiotic and ectoparasitic calamyzins have undifferentiated antennae and palps in a ventrolateral position; body ciliation appears to be absent. Jaws, if present, are of platelet/stylet type ( Watson et al. 2016) or have a modified stylet shape ( Aguado et al. 2013). Cryptic live colouring, camerate neurochaetal shafts in Calamyzas and platelet/stylet type jaws in the obligate symbiont Shinkai are revealed for the first time in this study (see below).