Paxtonia amoureuxi Budaeva & Fauchald 2011, COMB. NOV.
Creators: name: Budaeva, Nataliya
name: Fauchald, Kristian
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Eunicida
Onuphidae
Paxtonia
Paxtonia amoureuxi

description: PAXTONIA AMOUREUXI (INTES & LE LOEUFF, 1975) COMB. NOV. (FIGS 83–85)   
 Onuphis amoureuxi Intes & Le Loeuff, 1975: 313–314,   
 fig. 10h–q. Fauchald, 1982: 96–97, fig. 15d–e. Paradiopatra amoureuxi Paxton, 1986a: 38.   
 Type material: MNHN POLY TYPE 1245, ORSTOM Expedition, off Côte d’Ivoire, 5.1°N, 4.333°W, 80 m, 25 November 1966, dredge, coll. Intes, A. and Le Loeuff, P. (holotype); MNHN POLY TYPE 1343, ORSTOM Expedition, off Côte d’Ivoire, 5.033°N, 4.15°W, 170 m, 24 November 1966, dredge, coll. Intes, A. and Le Loeuff, P. (one paratype); MNHN POLY TYPE 1354, the same locality as another paratype (one paratype).   
 Non-type material examined: ZMUB, Fridtjof Nansen, Gulf of Guinea, off Nigeria, St. N 04A (one); St. N04D (one); St. N10B (one).   
 Type locality: Atlantic Ocean, West Africa, off Côte d’Ivoire, 5.1°N, 4.333°W, 80 m.   
 Diagnosis: First eight pairs of parapodia modified and directing slightly anteriorly; first five chaetigers with indistinctly bidentate pseudocompound falcigers, and pseudocompound tapering chaetae with moderately long pointed hoods; parapodial pockets present on chaetigers 6–25; branchiae pectinate, with up to five filaments, starting from chaetiger 10 and continuing to the end of the body. Prechaetal lobes triangular to conical, distinct on all parapodia.   
 Description: All specimens incomplete; holotype with 54 chaetigers, 2.6 mm wide; two paratypes 4.3 and 4.7 mm wide for 54 and 77 chaetigers, respectively. The most complete non-type specimen consisting of several fragments, with about 230 chaetigers. Largest non-type specimen 4.2 mm wide. A fragment consisting of about 15 posteriormost chaetigers with pygidium was found among non-type specimens. Body dorsoventrally flattened, including anterior chaetigers, and lacking a distinct pigmentation pattern (Fig. 83A).   
Prostomium short and wide, with rounded anterior edge and one pair of ovoid frontal lips (Fig. 83B, C). Palps reaching chaetiger 2 (chaetiger 1); lateral antennae reaching chaetiger 22 (chaetigers 12–22). Median antenna remaining only in two specimens, reaching chaetiger 20 (chaetiger 16), which is longer than the lateral antennae (Fig. 83A–C).  
Ceratophores of lateral antennae with six or seven (between five and eight) rings without lateral projections. Palpophores and cerartophores of median antenna also without projections, with one ring less than the ceratophores of the lateral antennae. Nuchal grooves almost straight, with wide mid-dorsal separation. Relatively large eyes present near bases of lateral antennae (Fig. 83A). Peristomium about onethird as long as first chaetiger. Peristomial cirri present, slightly longer than peristomium (Fig. 83A, B).  
First seven (eight) pairs of parapodia modified, projecting laterally, directing slightly anteriorly, but not enlarged. Prechaetal lobes rounded (Fig. 83G). Postchaetal lobes large and triangular through anterior 10 to 13 chaetigers (Fig. 83G), later becoming smaller towards posterior region, but still distinct on the posteriormost parapodia. Parapodia of chaetigers 7–14 (chaetigers 6–23) with large parapodial pockets limited frontally by folds of tissue (Fig. 83A, G). Dorsal cirri slender, present on all parapodia. Digitiform ventral cirri present in first seven (eight) chaetigers; thereafter, replaced by transverse elongate glandular pads (Fig. 83A, C, G).  
First three pairs of parapodia with dorsal fascicle of two or three simple chaetae and ventral fascicle of four or five pseudocompound falcigers (Fig. 83H, I). Anterior falcigers with two indistinct teeth, moderately long pointed hoods and smooth shafts (Fig. 84D). Parapodia of chaetigers 4 or 5 (chaetiger 6) with pseudocompound tapering chaetae with paired pointed hoods, but lacking distinct teeth (Figs 83J, 84E). From chaetiger 6 (chaetiger 7), pseudocompound tapering chaetae replaced by simple tapering chaetae with pointed tips, which in turn are replaced by limbate chaetae on the following unmodified parapodia (Fig. 84A). Paired simple bidentate subacicular hooks with thin transparent hoods starting from chaetiger 19 (chaetigers 17–26) (Fig. 84B, C, F). Pectinate chaetae thin and delicate, with slightly oblique distal margin and 12–20 small teeth (Fig. 84G). Neuropodia with up to five or six pale transparent neuroaciculae (Fig. 83H–J, 84A–C).  
Branchiae pectinate, with up to four long slender filaments (Fig. 84B), starting at chaetiger 10 (chaetiger 9) (Fig. 83B), and continuing to the end of the body. Short branchiae present on all chaetigers of the single posterior fragment studied.  
Mandibles strong, whitish, with parallel slender shafts. Calcareous cutting plates with two distinct indentations (Fig. 83F). Maxillae dark brown, well sclerotized; maxillary formula (based on one specimen): Mx I = 1 + 1; Mx II = 6 + 8; Mx III = 7 + 0; Mx IV = 6 + 9; Mx V = 1 + 1; Mx VI = 1 + 1 (Fig. 83E).  
Pygidium with two very long and slender anal cirri and dorsal anus (Fig. 83D). Tubes unknown.  
 Distribution: West Africa, Gulf of Guinea (Fig. 85). Depth range 80– 170 m.
description: Published as part of Budaeva, Nataliya & Fauchald, Kristian, 2011, Phylogeny of the Diopatra generic complex with a revision of Paradiopatra Ehlres, 1887 (Polychaeta: Onuphidae), pp. 319-436 in Zoological Journal of the Linnean Society 163 (2) on pages 411-414, DOI: 10.1111/j.1096-3642.2011.00701.x, http://zenodo.org/record/5441262