Updated key to genera of Polynoinae sensu lato present in the Northeast Atlantic incl. the Mediterranean Sea

Based on Barnich & Fiege (2003, 2009, 2010), Barnich (2011), Barnich et al. (2017), Chambers & Muir (1997), Charles et al. (2014), Fiege & Barnich (2009), Hartmann-Schröder (1996), Jourde et. al (2015), Núñez et al. (2015), Pettibone (1963), Ravara & Cunha (2016), Taboada et al. (2019) and this study.

In order to allow for identification of anterior fragments, the current key avoids, where possible, the use of numbers of elytra and segments as main distinguishing character.

1. Dorsal tubercles T-shaped. (Cephalic peaks absent. Lateral antennae terminoventral. More than 15 pairs of elytra. More than 50 segments) ..................................................... Acholoe Claparède, 1870

– Dorsal tubercles nodular ................................................................................................................... 2

2. First three pairs of elytra modified, with translucent central area. (Cephalic peaks absent or present. Lateral antennae ventral. 15 pairs of elytra. Fewer than 50 segments) .............................................. ....................................................................................................... Gorgoniapolynoe Pettibone, 1991

– First three pairs of elytra not modified ............................................................................................. 3

3. Dorsum with one or more median nodules per segment, starting from segment 2. (Cephalic peaks absent. Lateral antennae ventral. 18 pairs of elytra. Fewer than 50 segments) .................................. ................................................................................................................... Bathynoe Ditlevsen, 1917

– Dorsum without median nodules in anterior segments (may start later) .......................................... 4

4. Prostomium with cephalic peaks (can be small or masked when prostomium in bad condition) .... 5

– Prostomium without cephalic peaks ............................................................................................... 18

5. Notochaetae with two kinds of tips. Lateral antennae ventral or terminoventral ............................. 6

– Notochaetae all with similar, stout tip. Lateral antennae ventral ...................................................... 9

6. Some notochaetae with slender furcate tip, most others with stout, entire tip. Cephalic peaks small. Lateral antennae terminoventral (15 pairs of elytra. Fewer than 50 segments) .................................. ................................................................................................................ Pettibonesia Nemésio, 2006

– Notochaetae different. Cephalic peaks obvious. Lateral antennae ventral ....................................... 7

7. Long notochaetae with stout, blunt tip, short notochaetae abruptly tapering to sharp, pointed tip (15 pairs of elytra. Fewer than 50 segments) ..................................... Neolagisca Barnich & Fiege, 2000

– Most notochaetae with elongate, capillary tip .................................................................................. 8

8. Neurochaetae all with short, unidentate tip. Notochaetae numerous. Elytra large, covering dorsum. Dorsum without median nodules (15 pairs of elytra. Fewer than 50 segments) ................................ .................................................................................................................... Gattyana McIntosh, 1897

– Neurochaetae with two types of tip: short, bi- or unidentate or elongate, capillary. Notochaetae few. Elytra small, leaving mid-dorsum uncovered. Dorsum with or without small median nodule starting in mid-body (15 pairs of elytra. More than 50 segments) ............................. Enipo Malmgren, 1866

9. Dorsum with large median nodule starting in mid-body. Cephalic peaks small. (15 pairs of elytra. More than 50 segments) ................................................................................ Polynoe Lamarck, 1818

– Dorsum without median nodules. Cephalic peaks obvious ............................................................ 10

10. Neurochaetae distally bill-shaped. Neuropodia elongate, without supra-acicular process (15 pairs of elytra. Fewer than 50 segments) ......................................................... Robertianella McIntosh, 1885

– Neurochaetae otherwise. Neuropodia with supra-acicular process .................................................11

11. Some neurochaetae with hairy, penicillate tip. (15–16 pairs of elytra. Fewer than 50 segments) ...... .......................................................................................................... Austrolaenilla Bergström, 1916

– Neurochaetae otherwise .................................................................................................................. 12

12. Some neurochaetae slender with furcate tip. (15 pairs of elytra. Fewer than 50 segments) ............... .................................................................................................................. Eucranta Malmgren, 1866

– Neurochaetae otherwise .................................................................................................................. 13

13. All neurochaetae with unidentate tip .............................................................................................. 14

– Neurochaetae with bi- and unidentate tip ....................................................................................... 15

14. Neurochaetae all with stout tip (15 pairs of elytra. Fewer than 50 segments) .................................... ....................................................................................................................... Eunoe Malmgren, 1866

– At least some neurochaetae with elongate, capillary tip (15 pairs of elytra. Fewer than 50 segments) ................................................................................................. Bylgides Chamberlin, 1919

15. Notopodium prominent. More than 50 segments, long tail uncovered by elytra. 15 pairs of elytra .. ................................................................................................................ Neopolynoe Loshamn, 1981

– Notopodium reduced. Fewer than 50 segments, dorsum covered by elytra or at most short tail uncovered ........................................................................................................................................ 16

16. Elytra 18 pairs (elytral characters distinctive) .................................. Acanthicolepis McIntosh, 1900

– Elytra 16 or 15 pairs ....................................................................................................................... 17

17. Elytra 16 pairs (elytral characters distinctive) ............................................. Leucia Malmgren, 1867

– Elytra 15 pairs (elytral characters distinctive) .......................................... Harmothoe Kinberg, 1856

18. Neurochaetae with semilunar pockets. Lateral antennae ventral .................................................... 19

– Neurochaetae without semilunar pockets. Lateral antennae ventral or terminoventral .................. 20

19. Neuropodial acicular lobe rounded, neuroaciculum not penetrating epidermis. Notochaetae with few, scattered rows of spines (15 pairs of elytra. More than 50 segments) ........................................ ..................................................................................................................... Adyte Saint-Jospeh, 1899

– Neuropodial acicular lobe pointed, neuroaciculum penetrating epidermis.Notochaetae with numerous rows of spines (15–16 pairs of elytra. Fewer than 50 segments) ............... Subadyte Pettibone, 1969

20. Anteriormost neuropodia with stout hooks. Lateral antennae ventral or terminoventral (15 pairs of elytra. Fewer than 50 segments) .................................................. Australaugeneria Pettibone, 1969

– Anteriormost neuropodia without hooks (15 pairs of elytra. Fewer than 50 segments) ................. 21

21. Lateral antennae terminoventral. Neurochaetae all stout. (Notopodium reduced) ............................. ............................................................................................................... Malmgrenia McIntosh, 1874

– Lateral antennae ventral. Neurochaetae with stout or capillary tip ................................................ 22

22. Notopodium reduced. Neurochaetae all with stout, entire tip. Notochaetae very few (2-3), stout with faint rows of spines ............................................................................................ Webbnesia gen. nov.

– Notopodium prominent. Most neurochaetae with slender, capillary tip, some with stout, furcate tip. Notochaetae few, very stout, acicular, smooth ......................................... Melaenis Malmgren, 1866