A further review of European Magelonidae (Annelida), including redescriptions of Magelona equilamellae and Magelona filiformis Author Mortimer, Kate Author Mills, Kimberley Author Jordana, Esther Author Pinedo, Susana Author Gil, João text Zootaxa 2020 2020-04-23 4767 1 89 114 journal article 22645 10.11646/zootaxa.4767.1.4 829a29de-aa93-4196-bb5d-79e9d6ce8744 1175-5334 3770151 urn:lsid:zoobank.org:pub:7B5EC00B-44DA-4A09-8B0A-3DCA78CD7C37 Key to adult Magelonidae species in European waters (adapted from Mortimer et al. 2011 and Fiege et al. 2000 ) 1. Specimens with eight thoracic chaetigers........................................ Octomagelona bizkaiensis ( Fig. 12 ) - Specimens with nine thoracic chaetigers............................................................2 ( Fig. 11 ) 2. Chaetiger 9 carrying specialised chaetae with mucronate tips................................................... 3 - Chaetiger 9 without specialised chaetae.................................................................... 4 3. Lateral pouches present between chaetigers 10 and 11. Notopodial postchaetal lamellae of chaetigers 1–8 with crenulate upper margins; superior dorsal lobes present on chaetigers (3) 4–8.................................... Magelona johnstoni - Lateral pouches not occurring until extreme posterior region. Thoracic notopodial postchaetal lamellae with smooth upper margins; no superior dorsal lobes on thoracic chaetigers........................................ Magelona mirabilis 4. Abdominal hooks bidentate, small, slender species........................................................... 5 - Abdominal hooks tridentate............................................................................. 6 5. Prostomium without prostomial horns, superior dorsal lobes absent................................. Magelona minuta - Prostomial horns, superior dorsal lobes present on thoracic chaetigers........... Magelona sp. Mud Volcano, Gulf of Cádiz 6. Prostomium with clearly distinct frontal horns.............................................................. 7 - Prostomium without frontal horns, or with a squared anterior margin (“rudimentary horns”).......................... 8 7. Prostomium wider than long, anterior margin crenulate. Thoracic superior dorsal lobes foliaceous........ Magelona wilsoni - Prostomium longer than wide, anterior margin smooth. Thoracic superior dorsal lobes slender......... Magelona lusitanica 8. Slender species; prostomium longer than wide, superior dorsal lobes present on chaetigers 1–8. Thoracic transverse bands just behind parapodia present................................................................ Magelona filiformis - Stout species; prostomium width equal to/or slight larger than length. No thoracic superior dorsal lobes. Thoracic pigment band between chaetigers 5–9 (N.B. fades in preserved specimens). Sediment covered paper-like tube may be present........... 9 9. Abdominal notopodial lateral lamellae much larger than neuropodial. Neuropodial lamellae of posterior thorax ventral beneath chaetal bundle............................................................................ Magelona alleni - Abdominal lateral lamellae of roughly equal size in both rami. Neuropodial lamellae of posterior thorax in a distinctly postchaetal position..................................................................... Magelona equilamellae