Leodice ivanildae Souza, Zapff, Christoffersen & Zanol, 2024, new species
Creators: name: Souza, Thaís Kananda Da Silva
name: Zapff, Luana
name: Christoffersen, Martin Lindsey
name: Zanol, Joana
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Eunicida
Eunicidae
Leodice
Leodice ivanildae

description: Leodice ivanildae, new species
(Figs 2, 3, Table 2)
Material examined. HOLOTYPE, complete specimen, station 89 (MNRJP-007863). PARATYPES, 21 specimens; one complete specimen, station 2 (MNRJP-007865); one incomplete specimen, station 3 (MNRJP-007864); one complete specimen, station 5 (MNRJP-007866); one incomplete specimen, station 11 (MNRJP-007867); one incomplete specimen, station 33 (MNRJP-007868); one incomplete specimen, station 39 (MNRJP-007869); one complete specimen, station 46 (POLY-UFPB-1961); one complete specimen, station 47 (POLY-UFPB-1958); one incomplete specimen, station 48 (POLY-UFPB-1959); one incomplete specimen, station 49 (MNRJP-007871); one complete specimen, station 53 (MZUSP-6104); one complete specimen, station 54 (POLY-UFPB-1957); one incomplete specimen, station 55 (POLY-UFPB-1954); one incomplete specimen, station 57 (MNRJP-007870); one incomplete specimen, station 62 (POLY-UFPB-1962); one incomplete specimen, station 80 (POLY-UFPB-2081); one incomplete specimen, station 45 (POLY-UFPB-1960); one incomplete specimen, station 88 (POLY-UFPB-1968); one incomplete and three complete specimens, station 93 (POLY-UFPB-1972, MZUSP-6103, ZUEC-POL 25422, ZUEC-POL 25423).
Description. Complete holotype with 174 chaetigers, L10 6 mm, total length 100 mm, W10 without parapodium 2 mm. Paratypes 10 incomplete specimens with 67–149 chaetigers and 11 complete specimens with 143–159 chaetigers, total length of complete specimens 76–104 mm, L10 6–8 mm. W10 without parapodium 2–3 mm segment 5–20. Prostomium bilobed with deep median groove, rounded (truncated) anteriorly, flattened dorsally; shallower, shorter, and narrower than peristomium. Prostomial appendages evenly spaced in semicircle. Palpophores and ceratophores short and ring–shaped, without articulations. Ceratostyles and palpostyles tapering to thin tips with regular, moniliform articulations (Fig. 2C). Median antenna about one third longer than lateral antennae, lateral antennae about twice as long as palps (Fig. 2A, B, C); palps with 8 (6–9) articulations, reaching anterior peristomial ring (first chaetiger); lateral antennae with 19 (11–22) articulations, reaching chaetiger 6 (3–6); median antenna with 28 (15–35) articulations, reaching chaetiger 10 (5–13). Pair of eyes present, lateral to lateral antennae.
Peristomium cylindrical, laterally longer than medially (Fig. 2A, B, C); dorsal anterior margin covering base of median antenna; with conspicuously inflated ventrolateral lips. First peristomial ring about ¾ of total length, separation between rings visible dorsally and ventrally, not visible laterally (Fig. 2B, C). Thin, tapering peristomial cirri with 7 (5–11) cylindrical articulations, reaching anterior margin of prostomium.
Maxillary formula: 1+1; 6 (5–7)+6(5–8); 7(6–8)+0; 5(5–7)+9(8–11); 1+1; 1+1 (Fig. 2D). MxI with extended falcal arch, arched outer edge, rectangular; basal inner edge with curvature, where most posterior region of MxII fits; MxIII partially ventral to MxII, part distal arch with left MxIV; MxV with a prominent tooth; MxVI drop-shape. MxIV left attachment lamella tapering on left side, semi-circular in shape on right (Fig. 2D).
Branchiae pectinate with slender digitiform axis and filaments, present from chaetiger 4 (3–4) to 46 (38–51) (Fig. 3D); first branchiae with two short filaments; maximum number of filaments 7 (5–13) on chaetiger 15 (9–23); branchial filaments longer than central axis and both longer than notopodial cirri where best developed; branchial filaments reduce in length and number from middle of branchial distribution. Anterior and median parapodia with rounded chaetal lobes, aciculae emerging on dorsally; median parapodia narrower pointed, with aciculae emerging medially.
Prechaetal lobes low transverse folds along the body. Anterior and median postchaetal lobes longer than chaetal lobes and rounded; posterior postchaetal lobes low transverse folds, shorter than chaetal lobes.
Notopodial cirri shorter towards posterior region. Anterior notopodial cirri basally inflated, tapering to thin tips with 5 (6–7) cylindrical articulations (Fig. 3G); median with 3 (4) articulations; posterior with 2 (3) articulations. Ventral cirri longer than chaetal lobe along the body, basally inflated from chaetiger 3 (4) to 73 (55–73). Inflated base short, tapering to digitiform tips, slightly tapering from median chaetigers to posterior end (Fig. 3A).
Limbate chaetae, tapering, serrated marginally, longer in posterior parapodia. Pectinate chaetae with curved blades, 10–12 teeth, marginal teeth unequal in length and longer than other teeth (Fig. 3D, F). Compound falcigers chaetae bidentate; anterior parapodia, article tapering abruptly from proximal to distal end, proximal tooth laterally directed, shorter than distal tooth, guards slightly inflated and marginally serrated; in median and posterior parapodia articles longer and narrower than in anterior parapodia, proximal tooth tapering, laterally directed, straight, longer, and thicker than laterally directed distal tooth (Fig. 3B, H), guards more inflated than in anterior parapodia and coarsely serrated (Fig. 3E, I). Aciculae yellow, paired; distally expanded in anterior parapodia, becoming slightly curved and tapering in posterior chaetigers (Fig. 3A, C, D). Subacicular hooks yellow, bidentate, present from chaetiger 41(31–43); paired in some posterior chaetigers; guard leaf-shaped and partially covering proximal tooth; distal tooth thin, narrow, almost erect, and distally directed; proximal tooth larger than distal tooth, tapered, and laterally directed (Fig. 3C).
Pygidium with two pairs of pygidial cirri. Dorsal cirri digitiform, with about 9–10 articulations; five times longer than ventral cirri; ventral cirri digitiform, without articulations.
Variations. Specimens analyzed showed variation in: 1. total number of chaetigers, body width and length; 2. shape of prostomium, varying from rounded to truncated; 3. length of peristomium cirri, reaching either anterior margin of the prostomium or beyond it; 4. number of teeth of MxIII and MxIV; 5. beginning of branchial distribution; 6. maximum number of branchial filaments; 7. number of articulations of notopodial cirri in anterior, median and posterior parapodia; 8. number of teeth of pectinate chaetae; 9. beginning of subacicular hook distribution; 10. number of articulations of dorsal pygidial cirri.
Type locality. Southwest Atlantic Ocean, Continental Shelf along the coast of the State of Paraíba (Brazil), 6°29’S – 34°54’W, 17 m deep.
Distribution. Southwest Atlantic Ocean, Continental Shelf along the coast of the State of Paraíba (Brazil), 6°58’S, 34°46’W to 7°34’S, 34°45’W, 10–35 m deep (Fig. 1).
Etymology. The specific name is in honor of the mother of the first author, Ivanilda Maria, who supported the completion of the research.
Remarks. Among the species with branchiae restricted to the anterior body region, present in less than 55% of chaetigers, and with yellow bidentate subacicular hooks, Leodice ivanildae, sp. nov. is most similar to Leodice antillensis (Ehlers, 1887), Leodice articulata (Ehlers, 1887), Leodice mexicana (Fauchald, 1970), and Leodice websteri (Fauchald, 1969). It is clearly distinct from last three species, differing at least in the shape of articulations of antennae and palps (Table 2). Leodice ivanildae sp. nov. is most similar to L. antillensis. Both species also share articulated notopodial cirri along the whole body, 1–2 subacicular hooks per parapodium, and pectinate chaetae with both marginal teeth longer than the others. However, in L. antillensis antennae and palps have cylindrical, irregular articulations, pectinate branchiae are shorter than notopodial cirri and do not decrease in size from the middle of branchial distribution, and pectinate chaetae have flat blades. In L. ivanildae sp. nov. palps and antennae articulations are moniliform, pectinate branchiae are longer than notopodial cirri where best developed, decreasing in length from the middle of branchial distribution, and pectinate chaetae have curved blades. Thus, this species is here considered new to science.
description: Published as part of Souza, Thaís Kananda Da Silva, Zapff, Luana, Christoffersen, Martin Lindsey & Zanol, Joana, 2024, Taxonomy of Leodice Lamarck, 1818 (Annelida, Eunicidae) from Northeast Brazil (Tropical Southwest Atlantic Ocean) with description of a new species, pp. 151-175 in Zootaxa 5492 (2) on pages 156-160, DOI: 10.11646/zootaxa.5492.2.1, http://zenodo.org/record/13219174