Leptoecia

Budaeva, Nataliya, 2012, Leptoecia midatlantica, a new species of the deep-sea quill-worms (Polychaeta: Onuphidae: Hyalinoeciinae) from the Mid-Atlantic Ridge, Zootaxa 3176, pp. 45-60 : 51

Key to species of the Leptoecia

1. Only first pair of parapodia with falcigers.................................................................. 2

- Two first pairs of parapodia with falcigers.................................................................. 6

2. Bidentate falcigers present at least in some parapodia......................................................... 3

- All falcigers unidentate....................................................................... L. abyssorum

3. Dorsal cirri present till chaetiger 7–8, falcigers pseudocompound...................................... L. oxyrhincha

- Dorsal cirri present at least till chaetiger 30, falcigers simple................................................... 4

4. Subacicular hooks from chaetiger 12–13........................................................... L. vivipara

- Subacicular hooks after chaetiger 22...................................................................... 5

5. Only bidentate falcigers with subdistal reduction in diameter present; tubes circular in cross-section, rarely with longitudinal ribs along one or both sides................................................................... L. benthaliana

- Both uni-and bidentate falcigers usually present, rarely only bidentate falcigers present; falcigers straight, without subdistal reduction in diameter; tubes always dorsoventrally flattened with longitudinal ribs along both sides................................................................................................ Leptoecia midatlantica sp. nov.

6. Falcigers pseudocompound, tubes circular in cross-section, subacicular hooks from chaetiger 12–13................................................................................................... L. ultraabyssalis comb. nov.

- All falcigers simple, tubes flattened, subacicular hooks after chaetiger 31................................. L. apalpata