Key to species of Leocrates Kinberg, 1866, restricted

1 Anterior eyes small (each 1 / 10 – 1 / 15 prostomial width).......................................................... 2

- Anterior eyes large (each 1 / 4 – 1 / 6 prostomial width)........................................................... 7

2(1) Anterior eyes larger than posterior ones.................................................................... 3

- Anterior eyes small (each 1 / 10 prostomial width), smaller than posterior ones; notacicular lobes smooth; palpophores 1.5–2.5 times longer than palpostyles................................ L. harrisae n. sp. Eastern Pacific, Revillagigedo Islands

3(2) Notacicular lobes tapered; neurochaetae abundant (20–50 per bundle)............................................ 4

- Notacicular lobes blunt; neurochaetae scarce (15–20 per bundle); anterior eyes each 1 / 15 prostomial width........................................................................................... L. reishi n. sp. Marshall Islands

4(3) Prostomium wider anteriorly, lateral margins straight......................................................... 5

- Prostomium wider medially, lateral margins curved; lateral pharynx vesicles tapered; anterior eyes each 1 / 12 prostomial width (body pale)........................................................................ L. ahlfeldae n. sp. India

5(4) Middle chaetigers with about 20(–30) neurochaetae per bundle; pharynx vesicles tapered............................ 6

- Middle chaetigers with about 35 (20–50) neurochaetae per bundle; neurochaetal blades 3–18 times longer than wide; neuracicular lobes longer than wide; pharynx vesicles globose; anterior eyes each 1 / 10 prostomial width................................................ L. chinensis Kinberg, 1866, Hong Kong, restricted (incl. L. anonymous Hessle, 1925 from Japan)

6(5) Neurochaetal blades 3–10 times longer than wide; neuracicular lobes as long as wide; notacicular lobes tapered; anterior eyes each 1 / 10 prostomial width....................................................... L. giardi Gravier, 1900 Red Sea

- Neurochaetal blades 2–8 times longer than wide; neuracicular lobes wider than long; notacicular lobes blunt; anterior eyes each 1 / 12 prostomial width.................................... L. claparedii (Costa in Claparède, 1868), Mediterranean Sea

7(1) Anterior eyes larger than posterior ones.................................................................... 8

- Anterior and posterior eyes subequal, anterior eyes each 1 / 4 prostomial width; eyes reddish, anterior ones emarginate, posterior ones round; palpophores 2–3 times longer than palpostyles......................... L. rousei n. sp. Papua New Guinea

8(7) Notacicular lobes smooth, tapered, without lateral or distal projections........................................... 9

- Notacicular lobes with up to three small projections; eyes blackish round to emarginate; anterior eyes each 1 / 5 – 1 / 6 prostomial width..................................................................... L. mooreae n. sp. New Caledonia

9(8) Neuracicular lobes as long as wide; notacicular lobes 3 times longer than wide.................................... 10

- Neuracicular lobes wider than long; notacicular lobes twice longer than wide; palpophores up to twice longer than palpostyles; anterior eyes each 1 / 5 prostomial width.......................................... L. seidae n. sp. Papua New Guinea

10(9) Anterior eyes emarginate anteriorly, twice larger than posterior eyes; palpophores twice longer than palpostyles; anterior eyes each 1 / 6 prostomial width.......................................................... L. rizzoae n. sp. Seychelles

- Anterior eyes reniform, twice larger than posterior eyes; palpophores 2–3 times longer than palpostyles; anterior eyes each 1 / 5 prostomial width................................................ L. iris Grube, 1878 reinstated, Philippines / Samoa