Genus Paradoneis Hartman, 1965
Type species: Paraonis lyra Southern, 1914
Diagnosis: Body long, thin, slightly enlarged anteriorly. Prostomium variable in shape (conical, triangular, subtriangular, rounded or truncated anteriorly). Median antenna absent. Eyes usually absent. Prostomial ciliary bands present or absent. Longitudinal nuchal grooves along posterior prostomium margin. Peristomium indistinct or distinct dorsally. Three to six prebranchial segments; branchiae from chaetigers 4–7, numbering 5–48 pairs. All segments with notopodial postchaetal lobes; neuropodial lobes absent. Notochaetae include capillaries and either lyrate chaetae, modified spines, or simple curved spines; neurochaetae capillaries, a few species with curved neuropodial spines in posterior segments. Pygidium rounded terminally, with three anal cirri (Magalhães et al. 2018, Blake, 2019).
Key to species of Paradoneis modified from Martínez (2019). In square brackets is the region where the type locality is contained
1 Branchiae present.................................................................................... 2
- Branchiae absent................................. Paradoneis abranchiata Hartman, 1965 [Western North Atlantic]
2(1) One pair of branchiae.......................................... Paradoneis juvenalis (Hartmann-Schröder, 1974)
- Three or more pairs of branchiae......................................................................... 3
3(2) One kind of modified notochaetae....................................................................... 4
- Two kinds of modified notochaetae: lyriform in anterior chaetigers, acicular on median and posterior chaetigers......... 31
4(3) Modified notochaetae acicular or spinelike................................................................. 5
- Modified notochaetae lyriform.......................................................................... 8
5(4) Modified notochaetae spinelike.......................................................................... 6
- Modified notochaetae acicular.......................................................................... 7
6(5) Spinelike notochaetae straight, distally pointed; 6 prebranchial chaetigers; 8–10 pairs of branchiae..................................................................... Paradoneis drachi Laubier & Ramos, 1974 [Mediterranean Sea]
- Spinelike notochaetae curved, distally rounded; 4–5 prebranchial chaetigers; 12–20 pairs of branchiae................................................................. Paradoneis spinifera (Hobson, 1972) [Puget Sound, Washington]
7(5) Acicular notochaetae beginning in prebranchial chaetigers, three prebranchial chaetigers; 3–4 pairs of branchiae..................................................... Paradoneis perkinsi (McLelland & Gaston, 1994) [Northwest Florida]
- Acicular notochaetae beginning in branchial chaetigers, four prebranchial chaetigers; 10 pairs of branchiae................... Paradoneis magdalenaensis (de León-González, Hernández-Guevara & Rodríguez-Valencia, 2006) [Western Mexico]
8(4) Posterior chaetigers with spinelike neurochaetae............................................................ 9
- All neuropodia with capillary chaetae.................................................................... 11
9(8) Up to 18 pairs of branchiae; notopodial postchaetal lobes on prebranchial region papiliform; pygidium with four anal cirri................................................. Paradoneis andreae López & Sikorski, 2017 [Northeast Atlantic]
- Up to 12 pairs of branchiae; notopodial postchaetal lobes on prebranchial region tuberculate or triangular; pygidium with three anal cirri........................................................................................... 10
10(9) Up to 12 pairs of branchiae, marginally ciliated; notopodial postchaetal lobes on prebranchial region tuberculate; three long anal cirri, two ventrolateral and one midventral shorter than ventrolateral.................................................................................................. Paradoneis eliasoni Mackie, 1991 [Northern Europe]
- Up to 7 pairs of smooth branchiae; notopodial postchaetal lobes on prebranchial region distinctly triangular; three short, subequal anal cirri.................. Paradoneis strelzovi de León-González & Díaz-Castañeda, 2011 [Western Mexico]
11(8) Three prebranchial chaetigers.......................................................................... 12
- Four prebranchial chaetigers........................................................................... 29
12(11) Lyrate notochaetae starting on prebranchial region.......................................................... 13
- Lyrate notochaetae starting on branchial region............................................................ 21
13(12) Fifteen or more pairs of branchiae....................................................................... 14
- Up to 10 pairs of branchiae............................................................................ 26
14(13) More than 20 pairs of branchiae........................................................................ 15
- Up to 20 pairs of branchiae............................................................................ 16
15(14) Lyrate neurochaetae from chaetiger 2; with 23–26 pairs of branchiae....... Paradoneis nipponica (Imajima, 1973) [Japan]
- Lyrate neurochaetae from chaetiger 3; with 25–48 pairs of branchiae............................................................................................. P. kamaehu Magalhães, Bailey-Brock & Barroso, 2018 [Hawaii]
16(14) With 8–14 pairs of branchiae, longer than segment width; notopodial postchaetal lobes on branchial and postbranchial region (except in the last 4–5 chaetigers) similar in size............................................................................................ Paradoneis lyra guadalupensis (Amoureux, 1985) [Caribbean Sea, Guadaloupe Island] 1
- Up to 15 pairs of branchiae............................................................................ 17
17(16) A single type of lyrate notochaetae...................................................................... 18
- Several types of lyrate notochaetae...................................................................... 20
18(17) Branchiae of middle branchial region thin, digitiform; notopodial postchaetal lobes on prebranchial region digitiform........................................................... P. lyra (Southern, 1914) [Irish Exclusive Economic Zone]
- Branchiae of middle branchial region cirriform, elongated, basally thickened..................................... 19
19(18) Notopodial postchaetal lobes short, cirriform, increasing gradually in length on prebranchial region; in anterior part of branchial region digitiform, in middle and posterior part thick, finger-like, weakly jointed...................................................................................... P. longifurcata Erdoğan-Dereli & Çinar, 2019 [Sea of Marmara]
- Notopodial postchaetal lobes short, oval, getting longer on prebranchial region; on branchial region longer, finger-like; short, finger-like or elongated spindle-shaped to oblong oval on prebranchial region................................................................................. P. brunnea (Hartmann-Schröder & Rosenfeldt, 1988) [Southern Ocean]
20(17) Lyrate notochaetae on prebranchial and branchial region with equal branch thickness and pilose handle; those of postbranchial region similar to anterior ones but without pilose handle; from chaetiger 19, two types of lyrate chaetae (equal and unequal branch thickness) present on the same parapodium........ P. heterochaeta Erdoğan-Dereli & Çinar, 2019 [ Sea of Marmara]
- Lyrate notochaetae of two types, from branchial region having distal portion long with thin inner teeth; postbranchial lyriform notochaetae with distal part short and stout, with inner teeth stouter............................................................. P. mexicanensis Quintanar-Retama, Hernández-Alcántara & Solís-Weiss, 2019 [ Southern Gulf of Mexico]
21(12) Postbranchial lyrate notochaetae with tines of equal thickness along body........................................ 22
- Lyrate notochaetae with equal tine thickness in anterior region; unequal thickness in posterior region............................................................................. Paradoneis ilvana Castelli, 1985 [Mediterranean Sea]
22(21) Notopodial postchaetal lobes on prebranchial region not visible....... Paradoneis lyra capensis (Day, 1955) [South Africa] 2
- Notopodial postchaetal lobes on prebranchial region remarkably visible......................................... 23
23(22) Notopodial postchaetal lobes on prebranchial region conical, uniform in length; 15–17 pairs of branchiae in adult specimens, slightly shorter than segment width............................ Paradoneis forticirrata (Strelzov, 1973) [West Pacific]
- Notopodial postchaetal lobes on prebranchial region conical or triangular, progressively increases in size; up to 14 pairs of branchiae........................................................................................... 24
24(23) Branchiae longer than body width, pygidium with two long mid-lateral cirri and one short mid-ventral cirrus............................. P. carmelitensis Arriaga-Hernández, Hernández-Alcántara & Solís-Weiss, 2013 [ Southern Gulf of Mexico]
- Branchiae shorter than body width, pygidium with three short equal anal cirri.................................... 25
25(24) Prostomium bluntly conical.............................. Paradoneis lyra (Southern, 1914) in partim [North Atlantic]
- Prostomium triangular, slightly longer than wide.................................................................... Paradoneis campechensis Quintanar-Retama, Hernández-Alcántara & Solís-Weiss, 2019 [ Southern Gulf of Mexico]
26(13) Three (rarely 4) pairs of branchiae; all notopodial postchaetal lobes on branchial region uniform in length........................................................ Paradoneis perdidoensis (McLelland & Gaston, 1994) [Northwest Florida]
- With up to 10 pairs of branchiae; last notopodial postchaetal lobe on branchial region clearly shorter than remainder...... 27
27(26) With 4–6 pairs of branchiae; lyrate chaetae with tines of equal thickness; notopodial postchaetal lobe digitiform on branchial chaetigers.......................................................................................... 28
- With 9–10 pairs of branchiae; lyrate notochaetae with tines of unequal thickness; notopodial postchaetal lobe on branchial chaetigers globular to subtriangular........................................................ P. mackiei sp. nov.
28(27) With 4–5 pairs of branchiae; pygidium with three anal cirri of similar size......................................................... P. yucatanensis Quintanar-Retama, Hernández-Alcántara & Solís-Weiss, 2019 [ Southern Gulf of Mexico]
- With 5–6 pairs of branchiae; pygidium with three anal cirri, two laterals filiform, and one ventral long and thick....................................................................... Paradoneis idoiae Martínez, 2019 [Bay of Biscay]
29(11) Postbranchial lyriform notochaetae with tines of similar thickness.............................................. 30
- Postbranchial lyriform notochaetae with tines of unequal thickness........................................................................................ Paradoneis bathyilvana Aguirrezabalaga & Gil, 2009 [Northeast Atlantic]
30(29) Up to 7 pairs of branchiae; postbranchial lyriform notochaetae with long hairs basally......................................................................... Paradoneis hirsuta Sardá, Gil, Taboada & Gili, 2009 [Mediterranean Sea]
- Up to 12 pairs of branchiae; postbranchial lyriform notochaetae with smooth shaft................................................................................ Paradoneis mikeli Aguirrezabalaga & Gil, 2009 [Northeast Atlantic]
31(3) Up to 19 pairs of branchiae, blunt distally; modified notochaetae lyriform in anterior chaetigers, acicular with subterminal spine on median and posterior chaetigers........................... Paradoneis armata Glémarec, 1966 [Northeast Atlantic]
- Up to 10 pairs of branchiae, rounded distally; modified notochaetae lyriform in anterior chaetigers, harpoon like in posterior chaetigers.................................................... Paradoneis harpagonea (Storch, 1967) [Red Sea]