Prosphaerosyllis marmarae, Çinar & Dagli & Açik, 2011

Çinar, Melih Ertan, Dagli, Ertan & Açik, Sermin, 2011, Annelids (Polychaeta and Oligochaeta) from the Sea of Marmara, with descriptions of five new species, Journal of Natural History 45 (33 - 34), pp. 2105-2143 : 2118-2124

Prosphaerosyllis marmarae sp. nov.

( Figures 2–4 )

Material examined

Holotype. ESFM-POL / 2008-48 , Sea of Marmara , Erdek, E 1, 40 ◦ 18 ′ 42 ′′ N, 27 ◦ 46 ′ 18 ′′ E, 9 August 2008, 17 m, muddy sand.

Paratype. ESFM-POL / 2008-49 , Sea of Marmara , Erdek, E 1, 40 ◦ 18 ′ 42 ′′ N, 27 ◦ 46 ′ 18 ′′ E, 9 August 2008, 17 m, muddy sand, eight specimens .

Description

Holotype complete, small, 1.56 mm long, 0.32 mm width, with 21 chaetigers ( Figure 2A ). Largest paratype complete 2.15 mm long, 0.26 mm wide, with 24 chaetigers. Pale yellow in colour. Prostomium somewhat rectangular, wider than long, partially covered by dorsal fold of peristomium, with four large eyes in trapezoidal arrangement, close to each other; two small anterior eyespots located anterior sides of lateral antennae ( Figure 2A,B ). Antennae pyriform, with bulbous bases and short tips, all similar in shape and size; median antenna inserted between posterior eyes, lateral antennae inserted on anterior margin of prostomium ( Figure 2B ). Palps short, stout, as long as prostomium, totally fused all along their length, with numerous, short, rounded (sometimes digitiform) papillae. Peristomium narrow, with two small, rounded papillae near tentacular cirri; ventral side of peristomium with five small papillae in a row ( Figure 4A ); a pair of tentacular cirri similar to antennae, but slightly smaller. Dorsal cirri present on all parapodia; all dorsal cirri similar to antennae in shape and size; cirrophore globular to rectangular in shape, with a rounded, rectractile cirrostyle ( Figure 2C,D ). Ventral cirri digitiform, shorter than parapodial lobe ( Figure 4A ). Dorsal papillae large (max. 8.7 µm long), with rounded or pointed tip ( Figure 2C ), only present at anterior part of dorsal cirri. Parapodia conical, provided with few small papillae; a large papilla on posterior ventral side and a small papilla on anterior dorsal side ( Figure 2C ). Anterior parapodia with seven falciger chaetae, with short, unidentate, slightly hooked blades, with seven or eight large marginal spines; superior falciger chaeta with large, inequal spines; inferior falciger chaetae with one to three unequal spines; basal spine larger; 7.8–10 µm long ( Figures 3A , 4B ). Five falciger chaetae on middle parapodia, with blades of 7.5–8.75 µm long; blades with four or five spines, basal spine larger. Four falciger chaetae on posterior parapodia, with blades of 7.5–8 µm long; blades with two to four small spines, basal spine relatively longer; blades more strongly hooked ( Figures 3B , 4C ). Dorsal simple chaeta from chaetiger 1, unidentate, provided with short marginal spines ( Figure 3C ). Ventral simple chaeta on last five posterior parapodia, sigmoid, smooth ( Figures 3D , 4D ). Acicula solitary, acuminate, with subdistal anlargement and rounded tip ( Figure 3E ). Pharynx everted in holotype, 190 µm long, 100 µm wide; occupying four segments (210 µm long, 125 µm wide in paratype); pharyngeal tooth small, oval, located near anterior quarter of the pharynx. Proventricle larger than pharynx, occupying four or five segments, 275 µm long, 155 µm wide, with 22 muscle cell rows. Pygidium with two pyriform anal cirri.

Remarks

Prosphaerosyllis marmarae sp. nov. is mainly characterized by the shape of antennae and cirri, the morphology of falcigers [short blade length (≤ 10 µm), strong, triangular long spines on superior falcigers of anterior parapodia], the location and size of the pharyngeal tooth and the arrangement of papillae. This species seems to be similar to Prosphaerosyllis campoyi (San Martín, Acero, Contonente and Gómez, 1982) , Prosphaerosyllis isabellae ( Nogueira, San Martín and Amaral, 2001) , Prosphaerosyllis brandhorsti ( Hartmann-Schröder 1965) , Prosphaerosyllis brevicirra ( Hartmann-Schröder 1960) , Prosphaerosyllis palpopapillata (Hartmann-Schröder 1992) and Prosphaerosyllis magnoculata (Hartmann-Schröder 1986) .

Prosphaerosyllis marmarae sp. nov. differs from P. campoyi in having a small, oval pharyngeal tooth located anteriorly (large, rhomboidal in P. campoyi ), serrated dorsal simple chaeta (smooth in P. campoyi ), densely papillated palps (scarcely papillated in P. campoyi ), lacking papillae in mid-dorsal part of segments (present in P. campoyi ), small, pyriform dorsal cirri on all parapodia (large, rectangular on posterior parapodia in P. campoyi ).

Prosphaerosyllis isabellae was originally described from the western Atlantic (Brazilian coast) by Nogueira et al. (2001) and subsequently found along the Australian coast ( San Martín 2005). This species also has a pair of papillated palps and a small pharyngeal tooth, but differs from P. marmarae in having dorsal cirri with long basal part (globular in P. marmarae ), cirrophores of dorsal cirri with several iridescent glands (no glands in P. marmarae ), pharynx with glands on chaetiger 1 (without glands in P. marmarae ), small spines on cutting edge of blades of falcigers (large spines in P. marmarae ), lack of spines on blades of posterior falcigers (present in P. marmarae ), numerous small papillae on dorsum of segments (absent in P. marmarae ) and proventricle with 32–36 muscle cell rows (22 rows in P. marmarae ).

Prosphaerosyllis brandhorsti differs from P. marmarae in having palps not densely papillated (densely papillated in P. marmarae ), a large pharyngeal tooth (small in P. marmarae ) and acicula only slightly bent (acuminate with subdistal enlargement in P. marmarae ).

Prosphaerosyllis brevicirra , which was originally described from the Red Sea ( Hartmann-Schröder 1960), is very similar morphologically to P. marmarae . However, it differs from P. marmarae in having palps not densely papillated (densely papillated in P. marmarae ), a large pharyngeal tooth (small in P. marmarae ), acicula slender with rounded tip (acuminate with subdistal enlargement in P. marmarae ) and papillae in mid-dorsal part of body (absent in P. marmarae ).

Prosphaerosyllis palpopapillata is another species with numerous papillae on palps; however, its antennae and dorsal cirri are longer and not pyriform in contrast to P. marmarae .

The Australian species Prosphaerosyllis magnoculata is similar to P. marmarae but differs from it in having a large pharyngeal tooth (small in P. marmarae ), palps not densely papillated (densely papillated in P. marmarae ), scattered small papillae on dorsum of segments (absent in P. marmarae ), inferior falciger chaetae without spines on blades (with spines in P. marmarae ) and proventricle as long as pharynx (proventricle longer than pharynx in P. marmarae ).

Etymology

This species name makes reference to the type locality, the Sea of Marmara .

Distribution

Sea of Marmara, at 17 m depth.

Key to species of Prosphaerosyllis recorded from the Mediterranean Sea

1. Dorsum without rows of distinct papillae................................. 2

Dorsum covered with rows of distinct papillae............................ 4

2. Dorsal cirri truncated.......................... P. adelae (San Martín, 1984)

Dorsal cirri pyriform.................................................... 3

3. Dorsal cirri distinctly shorter than parapodial lobes; palps densely papillated; blades of superior falciger chaetae with coarse spines... S. marmarae sp. nov.

Dorsal cirri longer than parapodial lobes; palps scarcely papillated; blades of superior falciger chaetae with minute spines....... S. tetralix (Eliason, 1920)

4. Two papillae located in midline of dorsum of middle segments distinctly longer than others.................... P. longipapillata (Hartmann-Schröder, 1979)

Papillae on dorsum similar in shape and size.............................. 5

5. Papillae on dorsum small; pharyngeal tooth large, rhomboidal; blades of falciger chaetae long (max. 20 µm), with a distinct dorso-ventral gradation.. ... ... ... ... ... ... ... ... ... ... ... ........ P. xarifae ( Hartmann-Schröder, 1960)

Papillae on dorsum large; pharyngeal tooth small; blades of falciger chaetae short (max. 15 µm), without a dorso-ventral gradation.. ... ... ... ... ... ... ... ... ... ... ..... P. campoyi San Martín, Acero, Contonente and Gómez, 1982

Figures

Figure 2. Prosphaerosyllis marmarae sp. nov. (A) Whole body, dorsal view, holotype (ESFM- POL/2008-48); (B) anterior part, dorsal view, holotype; (C) middle parapodium, dorsal view, holotype; (D) dorsal cirrus on middle parapodium. Scale bars: (A) 200 µm, (B) 75 µm, (C) 20 µm, (D) 10 µm.

Figure 3. Prosphaerosyllis marmarae sp. nov. (A) Falcigers on parapodium 3, holotype (ESFM- POL/2008-48); (B) falciger chaetae on parapodium 18, holotype; (C) dorsal simple chaeta, parapodium 15; (D) ventral simple chaeta, parapodium 20; (E) aciculum, parapodium 18. Scale bars: (A) 7.3 µm, (B) 8.7 µm, (C, D) 10 µm, (E) 12 µm.

Figure 4. Prosphaerosyllis marmarae sp. nov. (A) Anterior end, ventral view, paratype (ESFM- POL/2008-49); (B) falciger chaetae on parapodium 3; (C) falciger chaeta on parapodium 15; (D) ventral simple chaeta. Scale bars: (A) 100 µm, (B) 1.4 µm, (C) 1.3 µm, (D) 2.7 µm.