Sphaerodoridae (Annelida) of the deep Northwestern Atlantic, including remarkable new species of Euritmia and Sphaerephesia Author Capa, Maria Author Osborn, Karen J. Author Bakken, Torkild text ZooKeys 2016 615 1 32 http://dx.doi.org/10.3897/zookeys.615.9530 journal article http://dx.doi.org/10.3897/zookeys.615.9530 1313-2970-615-1 3C47DE97A10E4688A92A29F7F6155B72 Taxon classification Animalia Phyllodocida Sphaerodoridae Ephesiopsis Hartman & Fauchald, 1971 Ephesiopsis Hartman & Fauchald, 1971: 68; Fauchald 1974 : 270; Rizzo 2009 : 62-63 (in part); Capa et al. 2014 . Type species. Ephesiopsis guayanae Hartman & Fauchald, 1971. Diagnosis. Body long and slender. Two longitudinal rows of macrotubercles, one pair per segment, absent on first chaetiger. Macrotubercles sessile, with terminal papillae. Two longitudinal rows of microtubercles, one pair per segment, running parallel between macrotubercles. Additionally, papillae arranged in 4-5 transverse rows on dorsum and ventrum. Prostomial and peristomial appendages short, spherical or digitiform. Parapodia from chaetiger 2 with both simple and compound chaetae; hooks on first chaetiger absent or present. Remarks . The genus was originally erected and justified by the presence of both simple and compound chaetae in every chaetiger ( Hartman and Fauchald 1971 , Fauchald 1974 ), a condition different to that found in members of Ephesiella Chamberlin, 1919, with only compound or pseudo-compound chaetae ( Moore 1909 , Fauchald 1974 , Capa and Bakken 2015 , Capa et al. 2014 , 2016 ), or Sphaerodorum Oersted , 1843, with typically only simple chaetae ( Fauchald 1974 , Capa et al. 2014 , 2016 ). Otherwise, these three genera are very similar and they all share the general body shape, with slender bodies, the number and arrangement of epithelial tubercles, with two longitudinal rows of macrotubercles with a terminal papilla, two longitudinal rows of microtubercles, and about 3‒4 transverse rows of smaller papillae on each segment. The re-examination of the types of the type species, Ephesiopsis guayanae Hartman & Fauchald, 1971, confirms the presence of sub-distally widened simple chaetae, with tapering tips and straight edges, and with apparently no sign of being compound under the light and compound microscopes (Fig. 1A, B); while an additional chaeta in same parapodia is compound, with thinner blades and with more rounded edges. It is unclear at this point, if the presence of both compound and apparently simple chaetae justifies the validity of the genus and further analyses should be performed to elucidate this issue. An examination of the types of the recently described Ephesiopsis shivae Rizzo, 2009 from Brazil revealed that the specimens do not show the typical generic attributes ( Rizzo 2009 , Fig. 3 A-C , E-F ). The chaetae considered in the original description as simple seem to be compound chaetae that have lost the blades, as it has been observed in many specimens of Ephesiella spp. Moreover, Ephesiella shivae was described as having a pygidium with four macrotubercles ( Rizzo 2009 ), but the examined Brazilian specimens showed the typical two dorsal macrotubercles and the ventral digitiform pygidial cirrus. Based on this observation, we propose that Ephesiella shivae is transferred to Ephesiella and conclude that Ephesiopsis is monotypic. Figure 1. Ephesiopsis guayanae paratypes LACM- AHF POLY TYPE 943, micrographs. A Mid-body chaetigers and chaetae (apparently simple), ventral view B Mid-body chaetigers with compound and simple chaetae, dorsal view.