Exogone (Parexogone) meridionalis ( Cognetti, 1955 ) Çinar & Gambi, 2005

Çinar, Melih Ertan & Gambi, Maria Cristina, 2005, Cognetti’s syllid collection (Polychaeta: Syllidae) deposited at the Museum of the Stazione Zoologica ‘‘ Anton Dohrn’ ’ (Naples, Italy), with descriptions of two new species of Autolytus, Journal of Natural History 39 (10), pp. 725-762 : 747-749

Exogone (Parexogone) meridionalis ( Cognetti, 1955) comb. nov.

( Figure 11 )

Exogone hebes meridionalis Cognetti 1955, p 5 –7, Figure 1-3-3b ; Cognetti 1957, p 61, Figure 11b .

Exogone parahomoseta mediterranea San Martín 1984, p 204 –208, Figure 45; San Martín 1991, p 728, Figure 7h, i ; Çınar et al. 2003, p 749.

Exogone mediterranea San Martín 2003, p 239 –241, Figures 127, 128.

Material examined

SZN-POL10, Lectotype, Station 4, Capo Posillipo, 1 October 1954, on sand with Branchiostoma lanceolatum , 5–10 m, coll. Cognetti; MNCN-16. 01/174, four specimens, 3 October 1980, Cala Sahona, Isla de Formentera, Balearic Islands , coll. and det. by San Martín; ESFM-POL/97-22 , one specimen, Izmir Bay, Aegean Sea, 7 November 1997, 76 m, muddy sand, coll. and det. by Çınar; ESFM-POL/97-21 , four specimens, northern Cyprus, 35 ° 3798"N–34 ° 2191"E, 15 May 1997, sand with Branchiostoma lanceolatum , coll. and det. by Çınar.

Description

Specimen complete, 1.52 mm long, 0.12 mm wide, H+ 1050.53 mm, for 30 chaetigers. Prostomium almost rectangular, wider than long, with two pairs of small eyes in rectangular arrangement; anterior ones larger ( Figure 11A ); with a pair of large ocular specks. Antennae emerging between anterior eyes on a transverse line; median one thick and long, reaching chaetiger 2; lateral antennae short, club-shaped, less than half length of median antenna, reaching anterior margin of prostomium. Palps thick, sub-triangular, completely fused, ca three times longer than prostomium. Peristomium fused with prostomium, with a pair of digitiform tentacular cirri. Dorsal cirri small, digitiform, absent on chaetiger 2; dorsal cirri on posterior parapodia longer than those on anterior ones. Parapodia conical, with a rounded papilla distally, bearing minute, numerous, shining granules internally. Ventral cirri digitiform, shorter than parapodial lobes. Falcigers on anterior parapodia numbering six, bidentate; blades with four to six coarse spines on cutting edges, ca 8 Mm long ( Figure 11B ). Falcigers on posterior parapodia morphologically similar to those on anterior parapodia but with shorter blades (ca 5 Mm long). Dorsal simple chaeta solitary, from chaetiger 1, thicker than shaft of falcigers on posterior parapodia, with a strong subdistal tooth, serrated subdistally ( Figure 11C ). Ventral simple chaeta solitary, only seen on posterior-most parapodia, sigmoid, strongly bidentate, serrated subdistally ( Figure 11D ). Acicula numbering one per parapodium, distally rounded ( Figure 11E ). Proventricle 0.21 mm long, 0.7 mm wide occupying ca 4.5 segments, with 34 muscle cell rows. Pharynx 1.5 times longer than proventricle, with one sinuation; 10 soft papillae at opening of pharynx; pharyngeal tooth large, triangular, placed just behind opening of pharynx. Pygidium with two long anal cirri ( Figure 11A ).

Remarks

Exogone (Parexogone) meridionalis comb. nov. is similar to the species E. (P.) hebes (Webster and Benedict, 1884) and E. parahomoseta Hartmann-Schröder, 1974 but differs from them in having six small eyes, long proventricle and dorsal simple chaetae serrated on concave edge.

Distribution

Western Mediterranean; Gulf of Naples ( Cognetti 1955, 1957), Balearic Islands (San Martín 1984) and Cala Cerrada, Murcia ( Campoy 1982). Eastern Mediterranean; Izmir Bay, Aegean Sea ( Çınar and Ergen 2002) and Cyprus ( Çınar et al. 2003). Western Atlantic; Florida ( San Martín 1991).

Parapionosyllis labronica Cognetti, 1965

Parapionosyllis minuta: Cognetti 1957 (in part), p 45 (non Pierantoni 1903).

Parapionosyllis labronica Cognetti 1965, p 68 , Figure 2d ; San Martín 1984, p 191–194, Figure 41.

Material examined

SZN-POL17, one specimen, Station 4, Capo Posillipo, on sand with Branchiostoma lanceolatum , 5–10 m, coll. Cognetti.

Notes

Specimen was placed ventro-dorsally on the slide and nearly dried out; complete, 3.38 mm long, 0.10 mm wide, H+ 1051 mm, for 27 chaetigers, pale yellowish with dark spots on dorsum of anterior segments. Falcigers unidentate, with a long subdistal spine, numbering seven and six on anterior parapodia and posterior ones, respectively; blades 7.5–10 Mm long throughout. Swimming chaetae four times longer than body width, from chaetiger 9. Proventricle 0.09 mm long, 0.08 mm wide, occupying one segment, with 18 muscle cell rows. Pharynx through four segments, with a tooth at opening of pharynx.

Distribution

Western Mediterranean ( Cognetti 1957, 1965; San Martín 1984), Eastern Mediterranean ( Çınar and Ergen 2002).

Figures

Figure 1. Map of the investigated area with location of sampling sites.

Figure 2. (A) Anterior and posterior parts of Autolytus antondohrni with a stolon; (B) trepan; (C) inferior falciger on anterior parapodium; (D) dorsal simple chaeta. Scale bar: 100 Mm (A); 11 Mm (B); 5 Mm (C, D).

Figure 3. (A) Anterior and posterior parts of Autolytus cognettii; (B) trepan; (C) falcigers on anterior parapodium; (D) dorsal simple chaeta. Scale bar: 100 Mm (A); 17 Mm (B); 4.3 Mm (C, D).

Figure 7. (A) Anterior and posterior parts of Autolytus rubropunctatus; (B) trepan; (C) falcigers on anterior parapodium; (D) dorsal simple chaeta; (E) aciculae on middle parapodium. Scale bar: 100 Mm (A); 21 Mm (B); 5 Mm (C–E).

Figure 11. (A) Anterior and posterior parts of Exogone (Parexogone) meridionalis; (B) falcigers on anterior parapodium; (C) dorsal simple chaeta; (D) ventral simple chaeta; (E) aciculum. Scale bar: 100 Mm (A); 3.5 Mm (B–E).