Paradiopatra

Key to species of Paradiopatra

1 Peristomial cirri absent (Fig. 1 C)........................................................................ 2

- Peristomial cirri present (Fig 3 C)........................................................................ 6

2 Branchiae present.................................................................................... 3

- Branchiae absent..................................................................................... 4

3 Branchiae from chaetiger 16 or later as single filaments (Fig 2 D)......................... Paradiopatra acirrata n. sp.

- Branchiae from chaetiger 8–10 with up to three filaments......................... Paradiopatra gracilis Imajima, 2009

4 Two anterior pairs of parapodia with subulate ventral cirri..................... Paradiopatra abyssalis (Imajima, 1999)

- Three anterior pairs of parapodia with subulate ventral cirri.................................................... 5

5 Pseudocompound falcigers present on the first four pairs of parapodia............ Paradiopatra antarctica (Monro, 1930)

- Simple falcigers present on the first three pairs of parapodia..................... Paradiopatra minuta (McIntosh, 1885)

6 Subacicular hooks starting from chaetiger 9, rarely from chaetigers 8–11.......................................... 7

- Subacicular hooks starting from chaetiger 12 or later........................................................ 26

7 Branchiae present.................................................................................... 8

- Branchiae absent.................................................................................... 21

8 Branchiae from chaetiger 3, rarely from chaetigers 4 or 5, well developed with not less than seven filaments............. 9

- Branchiae from chaetiger 6 (very rarely on chaetiger 5) or later, single or pectinate with not more than six branchial filaments.................................................................................................. 10

9 Best developed branchiae with 7–11 filaments; median antenna shorter than lateral antennae; pseudocompound falcigers with moderately long hoods...................................................... Paradiopatra parva (Moore, 1911)

- Best developed branchiae with 14–18 filaments; median antenna equal in length to lateral antennae; pseudocompound fal- cigers with long hoods.................................................. Paradiopatra furcatoseta (Monro, 1937)

10 Branchiae from chaetiger 6, rarely from chaetiger 7.......................................................... 11

- Branchiae from chaetiger 8 or later....................................................................... 16

11 Branchiae single, rarely bifid; median antenna more than half as long as lateral antennae........................... 12

- Branchiae pectinate, with more than three filaments in adults; median antenna less than half as long as lateral antennae... 13

12 Frontal lips ovoid; (Fig. 12 C); pseudocompound falcigers clearly bidentate........ Paradiopatra lepta (Chamberlin, 1919)

- Frontal lips trapeziform; pseudocompound falcigers indistinctly bidentate.... Paradiopatra litabranchia (Chamberlin, 1919)

13 Two anterior pairs of parapodia with subulate ventral cirri; pseudocompound falcigers with weakly developed distal append- ages and very long acutely pointed hoods................................................................. 14

- Three anterior pairs of parapodia with subulate ventral cirri; pseudocompound falcigers with well-developed distal appendages and moderately long pointed hoods..................................................................... 15

14 Subacicular hooks always from chaetiger 9............................... Paradiopatra quadricuspis (M. Sars, 1872)

- Subacicular hooks always from chaetiger 8.................................... Paradiopatra yasudai Imajima, 1999

15 Maxillae I with slender tapering distal parts; maxillae IV with 10–11 small teeth; simple tapering chaetae usually present on third pair of parapodia................................................... Paradiopatra pauli (Annenkova, 1952)

- Maxillae I with relatively wide distal shafts; maxillae IV with 5–6 large teeth; simple tapering chaetae absent................................................................................... Paradiopatra striata (Ushakov, 1950)

16 Uni- or tridentate pseudocompound falcigers present at least in some parapodia................................... 17

- All pseudocompound falcigers bidentate................................................................. 20

17 Four pairs of parapodia with bi- to tridentate pseudocompound falcigers............. Paradiopatra simplex Imajima, 1999

- Three pairs of parapodia with uni-, bi- or tridentate pseudocompound falcigers.................................... 18

18 Uni- to bidentate pseudocompound falcigers (Fig. 13 C–E); branchiae single or bifid.............................. 19

- Uni-, bi- and tridentate pseudocompound falcigers; branchiae present from chaetigers 16–17, usually with 4–5 (rarely between 6–8) filaments.......................................................... Paradiopatra ehlersi (McIntosh, 1885)

19 Branchiae as single filaments present for short region; subacicular hooks from chaetiger 9.................................................................................................. Paradiopatra variabilis n. sp. (in part)

- Branchiae single or bifid, continuing to posterior end; subacicular hooks from chaetigers 10–11................................................................................................ Paradiopatra crassa Imajima, 1999

20 Branchiae from chaetigers 10–13; median antenna equal in length or slightly shorter than lateral antennae; ceratophores with three or four rings; ventral cirri on modified parapodia digitiform.......... Paradiopatra bihanica (Intes & Le Loeff, 1975)

- Branchiae from chaetigers 7–9; median antenna less than half length of lateral antennae; ceratophores with 6–8 rings; ventral cirri on modified parapodia pyriform.............................. Paradiopatra pyricirra Budaeva & Fauchald, 2011

21 Frontal lips globular (Fig. 8 B); tubes covered with shell fragments, foraminiferans, echinoid spines, etc. (Fig. 8 A)...... 22

- Frontal lips ovoid (Fig. 12 C); tubes smooth, without foreign objects (tubes of P. imajimai, P. variabilis and P. longicappa unknown).......................................................................................... 23

22 Uni- to weakly bidentate falcigers (Fig. 9 B, C); eyes present; paired subacicular hooks unequal (Fig. 9 D)............................................................................................... Paradiopatra piccola n. sp.

- Clearly bidentate falcigers; eyes absent; paired subacicular hooks equal............. Paradiopatra fragosa (Ehlers, 1887)

23 First two pairs of parapodia with pseudocompound falcigers................................... P. longicappa n. sp.

- First three pairs of parapodia with pseudocompound falcigers................................................. 24

24 Two pairs of eyes present; postchaetal lobes present on first five pairs of parapodia....... Paradiopatra okai Imajima, 1999

- Eyes absent; postchaetal lobes present on first 8–9 pairs of parapodia........................................... 25

25 Pectinate chaetae with 13–15 teeth; mandibles slender with very large protomandibles (Fig. 4 D) Paradiopatra imajimai n. sp.

- Pectinate chaetae with 17–20 teeth; mandibles robust with moderately sized protomandibles (Fig. 13 G)....................................................................................... Paradiopatra variabilis n. sp. (in part)

26 Branchiae present from chaetigers 13–19, with up to four very long and slender filaments on median segments.............................................................................. Paradiopatra fauchaldi Buzhinskaya, 1985

- Branchiae absent.................................................................................... 27

27 Ceratophores of antennae with lateral projections (Fig. 7 A)................................................... 28

- Ceratophores of antennae without lateral projections......................................................... 30

28 Anterior modified parapodia with unidentate pseudocompound falcigers, rarely indistinctly bidentate pseudocompound fal- cigers, or simple or pseudocompound tapering chaetae..................... Paradiopatra hartmanae (Kirkegaard, 1980)

- Anterior modified parapodia with bi- and tridentate pseudocompound falcigers.................................... 29

29 First three pairs of parapodia with bi- and tridentate pseudocompound falcigers.... Paradiopatra papillata (Kucheruk 1979)

- First two pairs of parapodia with bi- and tridentate pseudocompound falcigers............................................................................................ Paradiopatra capbretonensis Aguirrezabalaga et al., 2002

30 Unidentate pseudocompound falcigers present at least in some anterior parapodia....... Paradiopatra unica Imajima, 1999

- Unidentate pseudocompound falcigers absent.............................................................. 31

31 Aciculae of anterior parapodia unusually long, extending as far as falcigers and limbate chaetae from prechaetal lobe (Fig. 11 A–C)...................................................................... Paradiopatra spinosa n. sp.

- Aciculae of anterior parapodia extending to about half length of falcigers or less from prechaetal lobe.................. 32

32 Four pairs of subulate ventral cirri; all pseudocompound falcigers clearly tridentate.. Paradiopatra fiordica (Fauchald, 1982)

- Three pairs of subulate ventral cirri; bi- and tridentate pseudocompound falcigers present............................................................................................... Paradiopatra hispanica (Amoureux, 1972)