Kuwaita hanneloreae, Arias, Andrés & Carrera-Parra, Luis F., 2014

Arias, Andrés & Carrera-Parra, Luis F., 2014, First record of the genus Kuwaita (Annelida: Lumbrineridae) in Europe with the description of a new species and new ultramorphological data for the genus, Zootaxa 3887 (1) : -

publication ID	https://doi.org/ 10.11646/zootaxa.3887.1.4
publication LSID	lsid:zoobank.org:pub:326DD7FC-3690-43E0-AB87-84C002352272
DOI	https://doi.org/10.5281/zenodo.6126101
persistent identifier	https://treatment.plazi.org/id/03AE878A-FFB8-FFC9-60B5-F96ADC92550D
treatment provided by	Plazi
scientific name	Kuwaita hanneloreae
status	sp. nov.

Treatment

Kuwaita hanneloreae View in CoL sp. nov.

Figures 1–6 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6

Material examined. Type material: Holotype: Villaviciosa estuary 43º 31' N, 5º 23'W, Asturias, northern Spain, Bay of Biscay, northeastern Atlantic, 20 April 2012, coll. A. Arias ( MNCN 16.01/13235). 15 Paratypes: same data as holotype, 5 specimens ( MNCN 16.01/13236, MNCN 16.01/15384, MNCN 16.01/15385, MNCN 16. 01/15386, MNCN 16.01/15387), 2 specimens ( NHMUK ANEA 2014.41–42), 3 specimens (AM W46970), 2 specimens (ECOSUR 0165); Villaviciosa estuary 43º 31' N, 5º 23'W, Asturias, northern Spain, Bay of Biscay, northeastern Atlantic, 9 April 2012, coll. A. Arias, 2 specimens ( MNCN 16.01/15388, MNCN 16.01/15389), 1 specimen (ECOSUR 0166). Non-type specimens: same data as holotype, 1 specimen (ECOSUR-P2669); Villaviciosa estuary 43º 31' N, 5º 23'W, Asturias, northern Spain, Bay of Biscay, northeastern Atlantic, 9 April 2012, coll. A. Arias, 2 specimens (ECOSUR-P2673).

Type locality. Villaviciosa estuary 43º 31'N, 5º 23'W, Asturias, northern Spain, Bay of Biscay, northeastern Atlantic.

Diagnosis. Prostomium with three small antennae protruding from nuchal fold; without eyes; nuchal organs forming almost closed circles. Notopodia well developed. Two types of chaetae: limbate capillary chaetae and simple multidentate hooded hooks with long hood in anterior chaetigers, and short hood in posterior ones with well defined proximal and distal teeth with several teeth between them. Posterior chaetigers with very small nephridial papillae. Branchiae reduced to little knobs in posterior parapodia. Pygidium with two pairs of anal cirri. Maxillary apparatus with five pairs of maxillae; maxillary carriers shorter than MI, anterior end slightly constricted; MI forceps-like with well developed attachment lamella; MII shorter than MI with wide strongly sclerotised connecting plates, with four teeth, distal tooth larger; MIII bidentate, distal tooth larger; MIV with large triangular tooth; MV free, prominent, lateral to MIV and MIII.

Description. Based on holotype, with variation of paratypes included in parenthesis. Holotype (MNCN 16.01/ 13235) complete specimen with about 370 chaetigers, L10= 10.1 mm, W10= 4.0 mm, TL= 29.6 cm in preserved condition (living specimen about 70 cm long). Living specimens with uniform bright orange to pinkish colour, highly iridescent ( Figs 1 View FIGURE 1 A-B). Ethanol stored animals cream coloured with iridescence still present ( Fig. 3 View FIGURE 3 A). Prostomium rounded, slightly wider (1.9 mm) than long (1.4 mm) ( Figs 1 View FIGURE 1 A, 2A, C-D); with three small, tapering antennae, hidden under nuchal fold ( Figs 1 View FIGURE 1 C, 3B); ventrally with well developed buccal lips ( Fig. 2 View FIGURE 2 D). Eyes lacking. Nuchal organs curved, forming nearly circles ( Fig. 2 View FIGURE 2 G). Peristomium represented by two apodous achaetous rings, slightly shorter than prostomium (1.1 mm) with first peristomial ring slightly larger than second ring ( Figs 1 View FIGURE 1 A, 2A, C, 3A); separation between rings distinct dorsally and laterally, ventrally first ring incomplete, second ring projecting forward as a muscular lip ( Fig. 1 View FIGURE 1 B). Both prostomium and peristomium with high density of sensory buds ( Figs. 2 View FIGURE 2 E-F).

Parapodia sub-biramous, well developed. First six smaller than following ones ( Fig. 2 View FIGURE 2 B). With short, globular dorsal cirri ( Figs 5 View FIGURE 5 A-C), best developed in median chaetigers, decreasing gradually in posterior ones, with several thin notoaciculae. Prechaetal lobe short, rounded in chaetigers 1–20 (1–[19–23]) ( Fig. 5 View FIGURE 5 A), from chaetiger 21 (20–22) to 120 becoming auricular and slightly longer, best developed in chaetigers 23–48 ( Fig. 5 View FIGURE 5 B); by chaetiger 121 becoming progressively shorter and rounded again. Postchaetal lobe in chaetigers 1–6 elongated ( Fig. 5 View FIGURE 5 B); from chaetiger 7 to 90 almost conical with wide base and directed dorsally, best developed in chaetigers 16–35 ( Fig. 5 View FIGURE 5 B); by chaetiger 91 becoming subulate; always longer than prechaetal lobe. Branchiae as small knob present from about chaetiger 150 to end of body. Ciliated sensory organ (Hayashi & Yamane organ) emerging laterally of body wall above notopodia in a shallow depression ( Fig. 4 View FIGURE 4 B-C, E-G) from chaetiger 1 to end of the body, being weakly developed in anterior chaetigers. Small nephridial papillae in ventral position from chaetiger 150 (134–215) to end of the body, best developed in posterior chaetigers ( Fig. 5 View FIGURE 5 D).

Parapodia with two bundles (fascicles) of chaetae. Anterior parapodia with following chaetal complement: supra-acicular fascicle consisting of six (six to eight) dorsal limbates, two uppermost limbates slender and longer than remaining four (four to six) lower limbates, and subacicular fascicle with six (six to ten) ventral limbates, all of equal length but shorter than dorsal ones ( Figs 4 View FIGURE 4 A, C); lowermost dorsal limbates present from chaetiger 1 to end of the body; ventral limbates from chaetiger 1 to chaetiger 44–45 (40–48). Subacicular simple multidentate hooded hooks (SMHH), usually six per parapodium (five to eight), replacing ventral limbates from chaetiger 43–44 (39–47). Supra-acicular simple multidentate hooded hooks, generally four per parapodium (four to six) replacing medial dorsal limbates by chaetiger 45 (40–48); SMHH from anterior chaetigers with long hood, proximal tooth short, rounded, followed with up to 16–18 small teeth ( Figs 5 View FIGURE 5 E, 6C); SMHH from median and posterior chaetigers with short hood, proximal tooth large, rounded, followed with up to 7–13 small teeth, and a short, rounded distal tooth ( Figs 5 View FIGURE 5 F, 6A, B, D). Aciculae yellowish, translucent with pointed tip and long mucro in anterior chaetigers, only one per parapodium; median chaetigers with blunt, translucent, distally reddish aciculae, two or three per parapodium; posterior chaetigers with two thick blunt aciculae, one translucent, other reddish. Pygidium with two pairs of anal cirri, most dorsal pair slightly longer than ventral one ( Fig. 1 View FIGURE 1 F).

Maxillary apparatus typical of Kuwaita ( Carrera-Parra, 2006a). Mandibles free along most of their length. With five pairs of maxillae. Maxillary carriers shorter than MI, anterior end slightly constricted; MI forceps-like with attachment lamella well developed; MII shorter than MI with wide strongly sclerotised connecting plates, with four teeth, distal tooth bigger; MIII bidentate, distal tooth bigger; MIV with large triangular tooth; MV free, prominent, lateral to MIV and MIII ( Figs 1 View FIGURE 1 D, 3C-D).

Variation. Wide range of sizes available, but in general complete preserved worms are moderate to relatively large specimens 25 to 38 cm long, with approx. 290–380 chaetigers. Largest collected living specimen 80 cm long with about 380 chaetigers. Material examined varied in L10 from 4 to 8.0 mm, in W10 from 1.9 to 4.1 mm and also varied in the following features: the first simple multidentate hooded hooks appeared from chaetiger 39 to 47; the end of ventral limbate chaetae ranged from chaetiger 40 to 48 and beginning of nephridial papillae varied from chaetiger 134 to 215. Most specimens had many broken chaetae, thus a statistical approach to the relationship between the size of the worms and the distribution of chaetae cannot be established.

Etymology. The new species is named in honour of Hannelore Paxton in recognition of her valuable contributions to the study of annelid polychaetes.

Distribution and ecology. Kuwaita hanneloreae sp. nov. is known from the southern part of the Bay of Biscay (northeastern Atlantic), from the intertidal sandy flats of the outer basin of Villaviciosa estuary (northern Spain). In its type locality this species is reported from a fine to medium sand Tellina tenuis da Costa community (Md, X = 0.27; SD = 0.05) with a mean organic matter content of 1.68% (SD = 0.27). Here, K. hanneloreae sp. nov. reaches densities over 4–5 individuals / m2 and occurs together with other lumbrinerids such as Scoletoma impatiens (Claparède) and Lumbrineris latreilli Audouin & Milne Edwards. Local fishermen from Villaviciosa commonly harvest lumbrinerid polychaetes, including K. hanneloreae sp. nov., at low tide for using as fishing-bait. Thus, this new species together with its congeners is highly appreciated as fishing bait and constitutes an important natural resource from this area.

Discussion. Currently, there are four valid species included in the genus Kuwaita , among these species, K. hanneloreae sp. nov. resembles K. magna (from Kuwait), K. papillifera (from Madagascar) and K. heteropoda (from Japan) by having a very late start of simple multidentate hooded hooks. However, K. hanneloreae sp. nov. and K. heteropoda differ from K. magna and K. papillifera in the development of nephridial papillae. The former species have small nephridial papillae, while the other species have well-developed papillae. Kuwaita hanneloreae sp. nov. differs from K. heteropoda by having MIII with distal tooth bigger and simple multidentate hooded hooks with well defined proximal and distal teeth with several teeth between them, while K. heteropoda has MIII with both teeth of similar size and simple multidentate hooded hooks with all teeth of similar size.