Diagnosis
provided by World Register of Marine Species
Spiochaetopterus Sars, 1853: Diagnosis [Modified after Britayev & Martin (2019), Moore et al 2017] Chaetopteridae with long peristomial palps and 3 distinct body regions. Prostomium sometimes a rounded and distinct dorsal lobe. Tagma A lacking separate notopodial cirri on A1, with 9-11 A chaetigers with lanceolate notochaetae, with only one emerged straight spine (cutting chaeta) on chaetiger 4. Pigmented ventral gland present on Tagma A. Tagma B with up to 20 chaetigers and multiple cupules, notopodia achaetigerous, bi- or tri-lobed, neuropodia with unicini. Tagma C with numerous segments with pointed achaetigerous notopodia, with neuropodia with pectinate uncini. Tube blind with 1 surface opening, usually not branched, tube walls of clean chitin-like material, annulated or smooth, with internal septa.
