Eusyllis lamelligera Marion & Bobretzky, 1875

Paresque, Karla, Fukuda, Marcelo Veronesi, Martín, Guillermo San & Nogueira, João Miguel De Matos, 2015, Amblyosyllis, Eusyllis, Odontosyllis, Perkinsyllis and Streptodonta (Annelida: Syllidae) from Brazil, with descriptions of two new species and new records for the country, Zootaxa 4000 (3), pp. 301-334 : 308-313

Eusyllis lamelligera Marion & Bobretzky, 1875

Figures 4–7

Eusyllis lamelligera Marion & Bobretzky, 1875: 33 , pl. 3, fig. 9A–C; Fauvel 1923: 294, fig. 113; San Martín 1984: 83 –87, lams. 11, 12D–F; 2003: 117, figs 54–55; San Martín & Hutchings 2006: 278 –280, figs 15–16; Fukuda 2010: 41 –44, fig. 9. Eusyllis dentata Hartmann-Schröder, 1990: 50 , figs 13–16.

Eusyllis habei Imajima, 1966: 97 , fig. 31A–K.

Material examined. Project 'BioPol-NE'. State of Paraíba, Baía da Traição, Praia do Farol (6°41.331'S 34°55.803'W), intertidal: 1 specimen ( MZUSP 2773), coll. 0 9 August 2010. Rio Tinto, Barra de Mamanguape (6°46.140'S 34°55.025'W), intertidal: 4 specimens ( MZUSP 2766), coll. 11 August 2010. João Pessoa, Cabo Branco (7°8.815'S 34°47.773'W), intertidal: 9 specimens ( MZUSP 2760), coll. 0 2 February 2010; Recife do Picãozinho (7°4.243'S 34°49.291'W), 1 m: 3 specimens ( MZUSP 2772), coll. 15 September 2012. Conde, Praia de Jacumã (7°16.535'S 34°47.969'W), intertidal: 1 specimen ( MZUSP 2763), coll. 29 January 2010. Pitimbu, Farol de Pitimbu (7°28.362'S 34°47.663'W), 1 m: 6 specimens ( MZUSP 2780), coll. 18 September 2012. State of Pernambuco, Goiana, Praia de Pontas de Pedra (7°36.927'S 34°48.296'W), intertidal: 1 specimen ( MZUSP 2781), coll. 13 December 2012. Ilha de Itamaracá, recifes de Itamaracá (7°43.944'S 34°49.2'W), 1 m: 3 specimens ( MZUSP 2778), coll. 15 December 2012. Project ‘ HABITATS’. State of Rio de Janeiro, Bacia de Campos, unconsolidated, van Veen grab: 21º22'58.704"S 40º19'44.429"W, 53 m: 1 specimen ( MZUSP 2774), 21 July 2009; 21º22'58.704"S 40º19'41.209"W, 53 m: 1 specimen ( MZUSP 2771), 21 July 2009; 21º9'9.705"S 40º16'6.779"W, 103 m: 1 specimen ( MZUSP 2776), 21 July 2009; 22º19'31.880"S 40º37'19.230"W, 73 m: 1 specimen ( MZUSP 2768), 0 3 July 2009; 22º52'2.108"S 40º57'29.073"W, 92 m: 1 specimen ( MZUSP 2775), 0 3 July 2009; 23º10'5.037"S 41º3'7.563"W, 107 m: 1 specimen ( MZUSP 2769), 0 2 July 2009; 23º10'5.207"S 41º3'6.453"W, 107 m: 4 specimens ( MZUSP 2770), 0 2 July 2009. Box Corer: 21º56'11.947"S 39º57'45.285"W, 720 m: 1 specimen ( MZUSP 2764), 0 7 February 2009; 22º7'39.877"S 39º54'15.005"W, 680 m: 1 specimen ( MZUSP 2765), 0 7 February 2009.

Additional material examined. Eusyllis lamelligera Marion & Bobretzky, 1875 . Spain: Baleares, Punta Galera, east of Isla Espardell, Ibiza (38º47'90"N 01º28'95"E), 3–6 m: 3 specimens ( MNCN 16.01/8680); 25 m: 1 specimen ( MNCN 16.01/8684), 0 6 July 1994, coll. & det. G. San Martín. Melilla: El Embudo, north of Isla del Congreso, Islas Chafarinas (35º11'01"N 02º26'16"W), 6 m: 3 specimens ( MNCN 16.01/8694); west side of Isla de Isabel II, Islas Chafarinas (35º10'59"N 02º25'43"W), 9–18 m: 1 specimen ( MNCN 16.01/8697), coll. 10 September 1991, coll. & det. E. López.

Description. Small to medium-sized body, fragile, largest specimen incomplete, 2.2 mm long, 0.25 mm wide, with 25 segments. Live specimens with two dark, thin transverse dorsal stripes per segment, one close to anterior border, another near posterior border of chaetigers, more evident on anterior segments; pigmentation frequently lost in preserved material. Palps broad, rounded, only basally fused ( Figs 4 A–G; 5A–B). Prostomium quadrangular with two pairs of eyes in trapezoidal arrangement, anterior eyespots absent ( Fig. 5 A); lateral antennae smooth, inserted on anterior margin of prostomium, 2–3 times longer than palps; median antenna inserted slightly posteriorly to lateral antennae ( Figs 4 A, C, E–F; 5A). Ciliated nuchal organs between prostomium and peristomium ( Fig. 4 A, C, E, F). Peristomium inconspicuous dorsally ( Fig. 4 A, C, E, F); dorsal peristomial cirri slightly shorter than median antenna, ventral peristomial cirri slightly shorter than dorsal peristomial cirri. Dorsal cirri of chaetiger 1 pseudoarticulated, ca. two times longer than lateral antennae, about 1.5 time as long as body width; dorsal cirri of chaetigers 2 and 5 short; dorsal cirri of chaetiger 3 slightly longer than those of chaetiger 2; dorsal cirri of chaetiger 4 longer, about same size as cirri of chaetiger 1; from chaetiger 6 onwards, dorsal cirri alternating long and short cirri, long cirri longer than body width at corresponding segment, short cirri slightly shorter than body width ( Fig. 5 C); tufts of cilia between bases of dorsal cirri and corresponding parapodial lobes ( Fig. 6 I–J). Antennae, peristomial and dorsal cirri throughout with short cirrophores and distally tapering cirrostyles ( Fig. 4 A, C, E, H). Ventral cirri of chaetiger 1 enlarged, flattened, foliaceous, inserted more mid-ventrally than remaining ventral cirri; ventral cirri from chaetiger 2 onwards ovate to pyriform, inserted near bases of parapodial lobes ( Fig. 4 B, D). Parapodial lobes conical ( Figs 4 A–B, H; 5A–C). Anterior parapodia with 10–18 falcigers each, midbody with ca. 12, posterior parapodia with 3–8 falcigers each; shafts of falcigers slightly spinulated, with straight tips ( Figs 6 E; 7A–B); blades of falcigers spinulated, bidentate, teeth of similar size, with rounded space in between ( Figs 6 A–G; 7A–B); blades with dorso-ventral gradation in length ( Figs 6 A, C, G; 7A–B), dorsalmost falcigers with blades 27– 13 µm long, ventralmost with blades 12–8 µm long in anterior and midbody parapodia, ca. 12 µm long in posterior parapodia. Dorsal simple chaetae present from midbody chaetigers, sigmoid, bidentate, thinner than shafts of falcigers ( Figs 6 H; 7C); ventral simple chaetae only present in posteriormost parapodia, bidentate, teeth of similar size, subdistally spinulated, about as thick as shafts of falcigers ( Fig. 7 D). Anterior parapodia with two aciculae each, midbody and posterior parapodia with single acicula each; aciculae with tricuspidate tip, progressively stouter posteriorwards ( Fig. 7 E–F). Pygidium semicircular, anal cirri missing in all specimens analysed. Pharynx through 4–5 segments, with anterior margin surrounded by crown of ca. 10 papillae ( Fig. 4 G); trepan with ca. 20 teeth dorsally and short serration ventrally; pharyngeal tooth large, conical to rhomboidal; proventricle through three segments, with 23–27 muscle cell rows ( Fig. 5 A).

Remarks. According to San Martín & Huchings (2006) and Brusa et al. (2013) this species has enlarged, flattened leaf-like ventral cirri on chaetiger 1, aciculae with tricuspidate tip, and compound chaetae with bidentate blades, with teeth of similar size, well separated from each other by rounded space. Considering this, San Martín & Huchings (2006) synonymised both E. dentata Hartmann-Schröder, 1990 and E. habei Imajima, 1966 with E. lamelligera . Later on, Brusa et al. (2013) also synonymised E. fragilis Hartman (1944) , E. tenera Verrill, 1882 and Desmosyllis longisetosa Verrill, 1900 with E. lamelligera .

Brazilian specimens of E. lamelligera resemble the Mediterranean ones, except in having a proventricle through three segments instead of ca. seven. The pigmentation of the Brazilian specimens is the first report of such character for this species, and colour patterns were absent in the specimens from other localities examined for comparison, but we cannot determine whether it was really absent in life or was lost as a result of fixation and preservation. Molecular studies are needed to confirm if this is a widely distributed species or a complex of sibling species.

Type locality. France, Gulf of Marseille (Mediterranean Sea).

Distribution. Atlantic Ocean: English Channel to Canary Islands, Mediterranean Sea, USA, Cuba, Brazil (Paraíba to São Paulo). Pacific Ocean: Japan, Australia (New South Wales, Tasmania). Indian Ocean: Australia (Western Australia).

Figures

FIGURE 4. Eusyllis lamelligera, SEM. (A), (B) anterior body, dorsal and ventral views, respectively; (C) anterior body, dorsal view; (D) detail of anterior body, ventral view; (E), (F) anterior body, lateral view; (G) everted pharynx, frontal view; (H) midbody, dorso-lateral view. Scale bars: A – C, H, 100 Μm; D – E, 50 Μm, F, 25 Μm; G, 20 Μm.

FIGURE 5. Eusyllis lamelligera. (A), (B) anterior body, dorsal and ventral views, respectively; (C) midbody, dorsal view. Scale bars: A – B, 0.3 mm; C, 0.2 mm.

FIGURE 6. Eusyllis lamelligera. (A) falcigers, anterior parapodia; (B) dorsalmost falciger, anterior parapodium; (C) falcigers, chaetiger 9; (D) falcigers, anterior parapodium; (E) dorsalmost falcigers, midbody parapodium; (F) ventralmost falciger, midbody parapodium; (G) falcigers, midbody parapodium; (H) dorsal simple chaeta, posterior parapodium; (I) posterior chaetiger, lateral view; arrow points to tuft of cilia between dorsal cirrus (cirrophore only remaining) and parapodial lobe; (J) close up view of the tuft of cilia between dorsal cirrus and parapodial lobe, posterior body. Scale bars: A, D, F – G, I, 20 Μm; B – C, E, 10 Μm; H, J, 5 Μm.

FIGURE 7. Eusyllis lamelligera. (A), (B) falcigers, anterior and midbody parapodia, respectively; (C) dorsal simple chaeta; (D) ventral simple chaeta; (E) aciculae, anterior parapodium; (F) acicula, posterior parapodium. Scale bars: A – F, 10 Μm.