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

A total of 36 syllid specimens preserved on permanent slides, which were collected and identified by G. Cognetti, and deposited at the Museum of the Stazione Zoologica “Anton Dohrn” in Naples, Italy, were re‐examined. Among the material, two new species of Autolytus, Autolytus antondohrni sp. nov. and A. cognettii sp. nov., were found and are described. Three new combinations are assigned: Autolytus mediterraneus (Cognetti, 1953), Exogone (Parexogone) meridionalis (Cognetti, 1955) and Syllis alternata Moore, 1908. Four lectotypes are designated for Autolytus convolutus Cognetti, 1953, A. mediterraneus (Cognetti, 1953), A. neapolitanus Cognetti, 1953 and Exogone (Parexogone) meridionalis (Cognetti, 1955). Proceraea scapularis (Claparède, 1864) is resurrected.


Introduction
The Stazione Zoologica of Naples, founded in 1872 by Anton Dohrn, represents one of the first marine biological stations of the world (Groeben 1984), and a leading institution in the history of research organization (Ghiselin and Groeben 2000;Groeben 2003) and marine life studies on biodiversity, especially for the Mediterranean Sea (Relini 2000). The collections of marine animals were organized very early in the activity of the Institute, and were first set up by the famous curator of the fishing service, Salvatore Lo Bianco, who collected marine organisms not only for specific research needs, but also for aquarium exhibitions and for sale (Relini 2000;Groeben 2003). However, this material has never been organized as a ''museum collection'', for exchange or cataloguing, but rather as an ''organisms reference'' for individual research work of different scientists during their stay at the Stazione (C. Groeben, personal communication). Nevertheless, the material actually present is of great importance, especially with respect to present-day comparisons of the Gulf of Naples biodiversity, with previous decades (Gambi et al. 2002). It is within this spirit that a project, co-ordinated by the curator of the public aquarium and of the collections, Dr Flegra Bentivegna and her collaborator Dr Isabella D'Ambra, for cataloguing and re-arrangement of the material has been promoted recently and is now in progress (Bentivegna 2000(Bentivegna -2001. The collections actually consist of more than 1500 taxa, belonging to different phyla, from Protozoa to Vertebrata, and were taken from several areas of the Gulf of Naples. Most of the material has been collected and classified by scientists working at the Stazione during their research stages, including some of the most famous taxonomists of their time, such as Dr Sarà (sponges), Drs Stekow and Brickmann-Voss (hydroids), Drs Jatta and Lo Bianco (cephalopods), Dr Ghirardelli (chaetognaths), Drs Tortonese and Montcharmont (echinoderms and fishes), and Dr Salfi (tunicates).
About 1650 different lots have been already re-catalogued, while polychaetes and crustaceans still need sufficient cataloguing numbers. The collection of polychaetes in particular was started around 1899 with the material of Eisig, who left 52 different species, both in jars and on slides. Other scientists who contributed later to the collection of marine worms were Jouin (eight species of interstitial families), La Greca (30 species), Cognetti (36 species), Parenzan (five species), and Lo Bianco, Bhaud and Sacchi (one species each) (Gambi et al. 1982). Among the scientists who contributed to the collections, Prof. Giuseppe Cognetti provided a set of slides of Syllidae, which corresponds to the material used for his monograph published in 1957, and which represents the material revised in this paper.
Prof. Giuseppe Cognetti, currently Professor Emeritus at the University of Pisa, was born in Livorno in 1928, and began his career as a polychaete specialist, working mainly on syllid taxonomy and reproductive biology. He started his studies at the Stazione Zoologica ''Anton Dohrn'' during three long periods, in the years 1953 (April to December), during the whole of 1954 and again in 1956 (April to December). During these periods he collected a great amount of material for taxonomic work on Syllidae from different areas of the Gulf of Naples and also made some observations on the reproductive biology of Autolytus. Prof. Cognetti then moved to the University of Modena where he worked as Professor of Zoology from 1958 to 1979. Then he moved to the University of Pisa where he organized and directed the ''Inter-Universitary Centre of Livorno'', and he also contributed to the foundation of the Department of Environmental Sciences, directed by him from 1986 to 1991. He is also one of the founders of the Italian Society of Marine Biology (SIBM), and member of different committees for the protection and conservation of marine habitats, and marine protected area designation. Apart from syllid taxonomy, in which he became a world-recognized specialist in the 1950s and 1960s, his research interest has also been directed to the ecology of marine worms, especially in polluted environments, to biological methodologies to detect environmental impact and pollution effects, and to marine conservation, especially of coastal and lagoonal habitats. For his research on marine organisms he was awarded the ''honoris causa'' degree in Sciences by the University of Orleans, France.
The aim of this paper is to revise the collection of syllids left by Prof. Cognetti at the Stazione Zoologica, to re-evaluate the role of taxonomic work and the old collections of material for biodiversity studies, and also as a tribute to his long and fruitful career on the occasion of his recent retirement.

Materials and methods
A total of 36 specimens of Syllidae preserved on permanent slides at the museum of Statzione Zoologica ''Anton Dohrn'' di Napoli (SZN), which were collected and identified by Giuseppe Cognetti during his work in 1953 at 11 stations located in the Gulf of Naples, western Mediterranean (Figure 1), were examined; two specimens (SZN-POL20 and SZN-POL30) are in very bad condition and thus could not be identified to species level. Details of the sampling methods, and characteristics of biotopes and stations were fully described in the paper by Cognetti (1957). The senior author (M.E.Ç .) examined Cognetti's syllid collection deposited in SZN during his scientific visit to the Laboratory of Ecology in Ischia via a NATO-B1 grant supported by TUBITAK (Ankara, Turkey).
Drawings of the specimens were made with the aid of a camera lucida. The length of the worms, the length of the head+first 10 chaetigerous segments (H+10) and the width at proventricular level (excluding parapodia and chaetae) were measured using an ocular micrometer. The museum abbreviations used in the text are as follows: SZN, Statzione Zoologica ''Anton Dohrn'' di Napoli, Italy; ESFM, Ege Ü niversitesi Su Ü rü nleri Fakü ltesi Mü zesi (Museum of Faculty of Fisheries Ege University), Bornova, Izmir, Turkey; and MNCNM, Museo Nacional de Ciencias Naturales de Madrid, Spain.

Description
Specimen complete, with stolon, female.

Remarks
Autolytus antondohrni sp. nov. can be easily distinguished from other Autolytus species by having a trepan with two, long, sharp lateral teeth, accompanied by eight small, blunt, equal teeth; a pair of nuchal epaulettes extending to posterior margin of chaetiger 1; short dorsal cirri, with small, spherical inclusions; two or three very large oily granules within parapodia and bases of dorsal cirri; and large spherical inclusions on dorsum of body after chaetiger 9. The most morphologically similar species to A. antondohrni is A. tyrrhenicus which has a trepan with two long lateral teeth accompanied with eight small ones.
However, the nature of the small teeth is different: sharp and triangular in A. tyrrhenicus; blunt and almost rectangular in A. antondohrni. The other difference between the two species is the distribution and types of granules within parapodia, cirri and dorsum of the body; dorsal cirri of A. tyrrhenicus include sparse needle-shaped granules ( Figure 8C), whereas A. antondohrni contains dense, spherical, amber-coloured inclusions. Parapodia of A. antondohrni contain two or three very large oily inclusions, whereas those of A. tyrrhenicus are pouch-like, expanded distally, containing dense, small spherical inclusions. Unlike A. tyrrhenicus, the dorsum of the body of A. antondohrni bears dense and spherical inclusions. The length and number of muscle cell rows of the proventiculus is another important difference; occupying 2.5 segments and having 26 muscle cell rows in A. antondohrni versus occupying two segments and having 20 muscle cell rows in A. tyrrhenicus. The median antenna of A. tyrrhenicus is longer than that of A. antondohrni. Finally, the prostomium of Sacconereis of A. tyrrhenicus is longer than that of A. antondohrni and bears relatively shorter antennae.

Etymology
The species is named after Anton Dohrn, founder of the Stazione Zoologica of Naples.

Distribution
Known only from the type locality (Mergellina, Gulf of Naples, western Mediterranean).

Description
Specimen complete, 4 mm long, 0.22 mm wide, H+1051.06 mm, for 35 chaetigers, yellowish. Prostomium rounded, wider than long, with two pairs of dark reddish eyes; anterior pairs larger and with lenses; one pair of ocular specks located on anterior margin of prostomium ( Figure 3A). Median antenna originating between anterior eyes, extending to chaetiger 18; lateral ones inserted in front of ocular specks, reaching chaetiger 7. Palps small, visible dorsally. Nuchal epaulettes distinct, reaching anterior margin of chaetiger 2. Peristomium narrow dorsally, with two pairs of tentacular cirri; dorsal ones two times longer than ventral ones, extending to chaetiger 8. Dorsal cirri on chaetiger 1 very long, subsequent ones longer than body width; cirrophores of all dorsal cirri less developed; shorter than parapodial lobes. Parapodia subtriangular. Falcigers numbering 10 and seven on anterior and posterior parapodia, respectively; shafts coarsely serrated at tip; blades bidentate; proximal tooth longer and thicker than distal one ( Figure 3C); blades of superior falcigers 7.5 mm long; those of inferior ones 10 mm long throughout. Dorsal simple chaeta bayonet-shaped, from chaetiger 3, subdistally serrated ( Figure 3D). Acicula numbering one throughout, thin, tapering. Proventricle 0.30 mm long, 0.18 mm wide, extending ca three segments, with 35 muscle cell rows. Pharynx between chaetigers 1 and 7, with one sinuation; trepan with a total of 30 teeth, arranged as four large, sharp, triangular teeth separated by seven to nine small, relatively blunt teeth ( Figure 3B). Pygidium with two long anal cirri ( Figure 3A).

Remarks
Autolytus cognettii sp. nov., which was labelled as A. benazzii Cognetti, 1953 by Cognetti, differs from A. benazzii in the morphology of the trepan (trepan with equal teeth in A. benazzii, trepan with unequal teeth in A. cognettii); length of dorsal cirri (much longer in A. cognettii) and cirrophores (much smaller in A. cognettii); length of median antenna (longer in A. cognettii). The figure of the trepan of the Madeira specimen (Plate 33, Figure 32), which was identified as Proceraea brachycephala Marenzeller, 1874 by Langerhans (1879), seems to be identical to that of A. cognettii. Langerhans (1879) also pointed out the difference between his specimen and Autolytus brachycephalus: ''Pharynx mit 30 Zähnen; bei meinem Exemplar waren nur drei davon grö sser, bei Marenzeller's wohl 8-10''. Gidholm (1966) then considered the Langerhans's record of A. brachycephalus as a synonym of A. langerhansi Gidholm, 1966, which is characterized by having cirrophores longer than parapodial lobes; a trepan consisting of 29-42 unequal teeth separated by three, four and five larger ones; well-developed infradental spines, and relatively large eyes. Autolytus cognettii seems to be similar to A. langerhansi, but differs from it by a number of characters; cirrophores (smaller than parapodial lobes in A. cognettii); median antenna (smaller in A. cognettii); nature of small teeth of the trepan (rectangular with pointed tip in A. cognettii, sharp and triangular in A. langerhansi); nature of large teeth of trepan (associated with small teeth in A. langerhansi; not associated in A. cognettii); and location of pharynx (between chaetigers 1 and 7 in A. cognettii, between chaetigers 3 and 8 in A. langerhansi).

Etymology
The species is named after Professor Guiseppe Cognetti in honour of his contributions to the taxonomy of Syllidae and ecology of polychaetes in the Mediterranean Sea.

Description
Specimen complete, 2.4 mm long, 0.12 mm wide, H+1050.72 mm, 41 chaetigers, pale yellowish. Prostomium oval, with two pairs of eyes in trapezoidal arrangement; anterior ones larger, without ocular specks ( Figure 4A). Palps small, completely fused to each other. Median antenna originating between anterior eyes, extending to chaetiger 6; lateral ones emerging from anterior margin of prostomium, reaching chaetiger 4. Peristomium distinct on dorsal side, with two pairs of tentacular cirri; dorsal ones longer, extending to chaetiger 5; ventral ones shorter, reaching chaetiger 3. Nuchal epaulettes reaching middle region of chaetiger 1. Dorsal cirri on chaetiger 1 reaching chaetiger 6. Except for dorsal cirri on chaetiger 2, remaining dorsal cirri shorter than body width, with less-developed cirrophores; shorter than parapodial lobes. Antennae, tentacular cirri and dorsal cirri on chaetigers 1 and 2 thicker than the rest; all having small, numerous inclusions within all the appendages; scarcely present within parapodia and dorsum of body. Parapodia, particularly in middle region of body, very thick, triangular in shape and with somewhat pointed tips. Falcigers on anterior parapodia numbering six, bidentate; proximal tooth thicker and longer than distal one ( Figure 4C); superior falcigers with blades 5 mm long and inferior ones with blades 7.5 mm long. Shafts of falcigers with tips coarsely serrated. Posterior parapodia with six falcigers, morphologically similar to those on anterior ones. Dorsal bayonet chaeta from chaetiger 1, slightly curved, with minute spines on tip ( Figure 4D). Proventricle 0.17 mm long, 0.11 mm wide, extending ca 2.5 segments, with 24 muscle cell rows. Pharynx with many sinuations, between chaetigers 3 and 7, with trepan consisting of nine equal, triangular, large teeth. Pygidium rectangular, with two small anal cirri.

Remarks
The report of Autolytus convolutus in the Red Sea and the Eastern Mediterranean by Ben-Eliahu (1977a) seems to be questionable as Ben-Eliahu's specimens have ocular specks on the prostomium (absent in Cognetti's specimen) and longer proventricle (occupying three segments in Ben-Eliahu's specimens versus two segments in Cognetti's specimen). Ben-Eliahu (1972) also reported this species from the Suez Canal with six eyes.

Remarks
Autolytus mediterraneus comb. nov. is similar to A. quindecimdentatus Langerhans, 1884 and A. hesperidum, Claparède 1864 in terms of pharyngeal armature; all of them have a trepan with 12-14 triangular, small, equal teeth. However, A. mediterrraneus differs from A. quindecimdentatus in having relatively long antennae, long dorsal cirri in the middle region of the body (longer than body width), short proventricle (occupying 1.5 segments versus 2.5 segments in A. quindecimdentatus). Autolytus hesperidium, which was originally described from the Gulf of Naples by Claparède (1868) and was erroneously proposed to be conspecific with A. prolifer (O. F. Mü ller, 1784) by Fauvel (1923), differs from A. mediterraneus in having median antenna as long as lateral ones (median antenna twice as long as lateral ones in A. mediterraneus), dorsal cirri from chaetiger 2 to posterior end of similar size (dorsal cirri on A. mediterraneus are alternating long and short) and long proventricle occupying two segments. However, the pygidium of A. hesperidium, which has two small projections together with two long anal cirri, termed as ''cirres spatulaires'' (see Claparède 1868, Plate 14, Figure 1A), appears to be similar to that of A. mediterraneus.

Distribution
Known only from the type locality; Secca della Gajola, Gulf of Naples, western Mediterranean (Cognetti 1953b).

Description
Specimen incomplete, anterior fragment, 1.75 mm long, 0.25 mm wide, H+1050.62 mm, for 27 chaetigers. Prostomium oval, with two pairs of reddish eyes in trapezoidal arrangement; anterior pair larger; one pair of ocular specks near anterior margin ( Figure  6A). Palps short, hardly visible dorsally. Median antenna originating between posterior eyes, very long, extending to chaetiger 23; lateral ones next to ocular specks, reaching chaetiger 11. Nuchal epaulettes indistinct, reaching anterior region of chaetiger 1. Peristomium distinct, with two pairs of tentacular cirri; dorsal ones long, extending to chaetiger 11; ventral ones reaching chaetiger 5. Dorsal cirri on chaetiger 1 very long, extending to chaetiger 17; those on chaetiger 2 longer than body width; remaining ones either equal to or shorter than body width. Cirrophores less developed. Large granules present on dorsum of body and within parapodia, but those within cirri and antennae very small, inconspicuous. Parapodia conical in shape, larger in anterior region. Falcigers numbering 10 on anterior parapodia, with shafts coarsely serrated at tip; blades bidentate, proximal tooth larger and longer than distal one ( Figure 6C); superior falcigers with blades 7.5 mm long; inferior ones with blades 10 mm long. Falcigers on middle parapodia numbering eight, morphologically similar to those on anterior parapodia but with shorter blades (5-7.5 mm long). Dorsal simple chaeta bayonet-shaped, from chaetiger 7, thin, slightly curved ( Figure 6D). Acicula numbering one per parapodium. Proventricle 0.28 mm long, 0.16 mm wide, through four segments, with 30 muscle cell rows. Pharynx between chaetigers 1 and 10, with one sinuation; trepan with 14 triangular, coarse, equal teeth ( Figure 6B).

Remarks
Although morphological features of the specimen of Autolytus neapolitanus we examined coincide with its original description, some differences were encountered; the number of teeth on the trepan of the specimen examined are 14, whereas Cognetti (1953c) reported it as 20. However, the morphology of the teeth (long, coarse and triangular) seems to be identical to the description. He also mentioned five red spots at the bases of pharyngeal papillae, but, probably due to preservation, the specimen we examined does not have such spots. However, the location of proventricle and pharynx as well as their relative length are similar to those reported by Cognetti (1953c). The other similarity between the material we examined and the Cognetti's description is the shape and length of antennae and cirri. Autolytus neapolitanus resembles A. quindecimdentatus Langerhans, 1884 in terms of the shape and the number of teeth of the trepan (see Gidholm 1966, Figure 7f); however, teeth of the former species are larger than those of the latter. In addition, A. neapolitanus has longer antennae and dorsal cirri than those of A. quindecimdentatus.

Description
Specimen complete, 7.5 mm long, 0.26 mm wide, H+1050.76 mm, for 96 chaetigers, yellowish, bearing pinkish spots on mid-dorsum of chaetigers 1-3, and on mid-and lateral dorsum of chaetigers 9-22 ( Figure 7A). Prostomium rectangular, with two pairs of large reddish eyes, very close to each other on either side; anterior pairs larger, with lenses, accompanied by small spherical reddish bodies. Palps visible dorsally, small, less than 0.25 length of prostomium. Median antenna originating between anterior eyes, extending back to chaetiger 10; lateral ones on anterior margin of prostomium, relatively short, reaching chaetiger 7. Nuchal epaulettes could not be seen on the specimen examined. Peristomium reduced dorsally, with two pairs of tentacular cirri; dorsal ones reaching chaetiger 8. Dorsal cirri on chaetiger 1 long, reaching chaetiger 11, subsequent ones longer or slightly shorter than body width, with less developed cirrophores; containing very large, amber-coloured inclusions. Parapodia rounded in anterior region, conical in posterior region. Falcigers on anterior parapodia numbering 14, strongly bidentate; proximal tooth larger than distal one, spines on cutting edge fine, indistinct ( Figure 7C); blades of superior falcigers 10 mm long, those of inferior ones 12.5 mm long. Falcigers on posterior parapodia numbering 10, bidentate, distal and proximal teeth almost similar in size but proximal one stronger; blades 5 mm (superior falcigers) to 7.5 mm (inferior falcigers) long. Aciculae numbering two per parapodium; one with truncated tip, other with tip bending at right angle ( Figure 7E). Dorsal simple chaeta bayonet-shaped, slightly re-curved, serrated distally and subdistally, only seen on posterior-most parapodia ( Figure 7D). Proventricle 0.55 mm long, 0.20 mm wide, through seven segments, with 40 muscle cell rows. Pharynx with one sinuation, between chaetigers 3 and 11; trepan with 30 almost equal sharp teeth ( Figure 7B). Pygidium with one pair of long anal cirri; wrinkled at base ( Figure 7A).

Remarks
The red spots on the dorsum, long dorsal cirri, large eyes, large granules within the cirri and antennae, ca 30 small, equal teeth on trepan, minute distal tooth of blades of falcigers and very long proventricle (occupying seven segments) characterize Autolytus rubropunctatus. The original description of this species is rather insufficient, but emphasizes the characteristic pigmentation on the dorsum and the large eyes.

Remarks
Autolytus tyrrhenicus displays close morphological affinity with A. antondohrni sp. nov., but differs from it by a number of characters discussed under ''Remarks'' section for A. antondohrni. The figure (Figure 1) drawn by Dales (1951) seems to be identical to A. tyrrhenicus in having a similar trepan and dorsal cirri. However, if it exists, the material collected and identified by Dales should be examined in order to reach a reliable conclusion.

Distribution
Known only from the type locality; Santa Lucia, Gulf of Naples, Western Mediterranean (Cognetti 1953b(Cognetti , 1957. Probably on the coast of England; Thames estuary (Dales 1951).

Description
Specimen complete, 12.5 mm long, 0.55 mm wide, H+1052.50 mm, for 76 chaetigers, yellowish, two black dorsolateral lines along body, from the conjunction of nuchal organs to chaetiger 13; lines becoming thicker towards posterior end; blackish pigmentation present along side of nuchal organs ( Figure 9A). Prostomium somewhat trapezoidal, with two pairs of large reddish eyes, overlapping; anterior eyes larger, accompanied by small spherical reddish bodies. Median antenna missing; its scar between eye pairs; lateral ones emerging from anterior margin of prostomium, tapering, ending with a blackish knob, extending to chaetiger 8. Palps small, visible dorsally. Nuchal epaulettes conspicuous, reaching middle region of chaetiger 2, with dense cilia only along outer margin; cilia on anterior-lateral margin of nuchal organs relatively longer, reaching level of anterior eyes ( Figure 9A). Peristomium narrow, with two pairs of tentacular cirri; dorsal ones long, reaching chaetiger 6; ventral ones extending to chaetiger 2. Dorsal cirri on chaetiger 1 long, reaching chaetiger 13, tip missing. Dorsal cirri on chaetiger 2 extending to chaetiger 5, with a blackish knobbed tip. Remaining dorsal cirri on anterior parapodia shorter than body width, relatively thin and without knobbed tip; dorsal cirri on middle and posterior parapodia shorter than those on anterior ones. Cirrophores of tentacular cirri and dorsal cirri on chaetigers 1 and 2 relatively well-developed; those of other dorsal cirri indistinct. Cirri and antennae with sparse spherical inclusions. Anterior parapodia large, somewhat rectangular in shape; posterior ones relatively short. Falcigers on anterior parapodia numbering six, with shafts coarsely serrated distally; blades bidentate, distal tooth shorter and thinner than proximal ( Figure 9C); spines on cutting edge indistinct; blades of superior falcigers 7.5 mm long, those of inferior ones 10 mm long. Falcigers on posterior parapodia numbering six, with relatively short blades, 5 mm (superior ones) to 7.5 mm (inferior ones) long; bidentate, distal and proximal teeth somewhat similar in size and thickness; blades of superior falcigers with concave cutting edge ( Figure 9D). Dorsal bayonet chaeta thick, with an arista 10 mm long, distally serrated, from chaetiger 14. Each parapodium with two distally rounded aciculae. Proventricle massive, 0.90 mm long, 0.47 mm wide, through 2.5 segments, with about 42 muscle cell rows. Pharynx with one sinuation, between chaetigers 3 and 7; trepan with nine larger, sharp teeth alternating with nine smaller, triangular teeth in two circlets; bases of lateral teeth with a prominent, triangular ridge ( Figure 9B). Pygidium conical, with two thick, short anal cirri.

Remarks
The morphological features of Cognetti's specimen nearly coincide with the original description and figures given by Claparède (1864). However, the Neapolitan specimen shows some discrepancies; eyes are relatively large and overlapping each other, whereas the figures drawn by Claparède show that eyes are small and in close trapezoidal arrangement; Cognetti's specimen has relatively longer lateral antennae and dorsal cirri on chaetiger 1 than Claparède's specimen; the tips of lateral antennae, tentacular cirri and dorsal cirri on chaetiger 1 and 2 of Cognetti's specimen are bulbous and black-coloured; this feature had not been noted in the original description of P. scapularis. Proceraea scapularis resembles P. picta Ehlers, 1864, which was originally described from the Adriatic Sea (Ehlers 1864), in having the same number of teeth in the trepan. However, P. scapularis differs from P. picta in a number of characters; the former has two black lateral lines on the dorsum of the body, whereas the latter has brown squares along lateral sides of the body; the nuchal epaulettes of P. scapularis have dense black pigmentation, whereas such pigmentation has not been reported on P. picta; in contrast to P. picta, palps of P. scapularis are visible dorsally. Proceraea okadai (Imajima 1966) from Japan has a close morphological similarity with P. scapularis in having two longitudinal black bands on dorso-lateral sides of the body, but P. okodai has shorter nuchal epaulettes (extending to anterior margin of chaetiger 1 in P. okadai versus to anterior margin of chaetiger 3 in P. scapularis).
Proceraea scapularis was previously reported from the western Mediterranean; type locality (Port-Vendres, Gulf of Lion) (Claparède 1864). Okada (1933) also reported this species around Plymouth, England. However, the previous records of Proceraea picta especially from the western Mediterranean should be re-examined to find out the ''true'' distributional pattern of P. scapularis.

Notes
Specimen complete, 2.35 mm long, 0.16 mm wide, H+1050.85 mm, for 35 chaetigers, yellowish with irregular black speckles on body. Prostomium with two pairs of eyes, overlapping on either side; anterior ones larger, with lenses; one pair of ocular specks ( Figure 10A). Median antenna emerging at middle of prostomium, six times longer than prostomium; lateral ones from anterior margin of prostomium. Nuchal epaulettes rounded, covered with dense, long cilia, extending beyond prostomium. Peristomium with two pairs of tentacular cirri; dorsal ones longer. Dorsal cirri alternating short and long; longer ones with black speckles. On ventral side of each parapodium, a ciliated ridge present ( Figure  10A). Anterior and posterior parapodia with three falcigers and one simple chaeta; falcigers bidentate; distal and proximal teeth somewhat equal; blades ca 5 mm long ( Figure 10B). Solitary dorsal simple chaeta expanded distally, with a tip accompanied by one long and five short spines ( Figure 10C). Each parapodium with one acicula, tapering. Proventricle 0.13 mm long, 0.10 mm wide, through three segments, with 30 muscle cell rows. Pharynx long, with three sinuations; trepan with short, equal teeth; number of teeth could not be counted due to contraction of tip of pharynx. Pygidium somewhat triangular, with one pair of short anal cirri ( Figure 10D).

Notes
Specimen complete, 2 mm long, 0.15 mm wide, H+1050.98 mm, for 21 chaetigers, with a total of 16 embryos of four chaetigers attaching to bases of parapodia after chaetiger 16; 0.25 mm long, 0.06 mm wide. Falcigers numbering eight on anterior parapodia, five on posterior ones; blades unidentate with a subdistal long spine, 10-40 mm long on anterior parapodia and 10-35 mm long on posterior parapodia. Proventricle 0.18 mm long, 0.13 mm wide, through two segments, with 26 muscle cell rows. Pharynx occupying ca four segments, with a pharyngeal tooth; coarse (50 mm long), triangular, sharp.

Notes
Specimen complete, 3.35 mm long, 0.14 mm wide, H+1050.84 mm, for 34 chaetigers. Median antennae longer than lateral ones, expanded distally, reaching tip of palps. Dorsal cirri ovoid, present on all chaetigers. Pseudospinigers numbering one or two, bifid, with a blade 27.5 mm long on anterior parapodia and 20 mm long on posterior parapodia. Falcigers numbering eight on anterior parapodia, four on posterior ones, bidentate; blades 7.5 mm and 5 mm long on anterior and posterior parapodia, respectively. Dorsal simple chaeta from chaetiger 1, serrated subdistally, pointed distally. Proventricle 0.18 mm long, 0.09 mm wide, occupying 2.5 segments, with 28 muscle cell rows. Pharynx through six segments, with a pharyngeal tooth at opening of pharynx.

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-Schrö der, 1974 but differs from them in having six small eyes, long proventricle and dorsal simple chaetae serrated on concave edge.

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
Mediterranean, Atlantic and Pacific Oceans (San .

Distribution
Mediterranean and Atlantic Ocean (San .

Distribution
Mediterranean, Atlantic and Indian Ocean (San .

Distribution
Mediterranean and Atlantic Ocean (San .

Remarks
The Red Sea specimens of Pionosyllis weismanni identified by Ben-Eliahu (1977b) differ from the Mediterranean and Madeira specimens in having only four eyes instead of six, suggesting that they might probably belong to a different species.

Distribution
Mediterranean, Atlantic and Pacific Ocean (San .

Distribution
Mediterranean, Red Sea and Atlantic Ocean (San .
Falcigers bidentate; blades 8.5-12 mm long on anterior parapodia, ca 7.5 mm on posterior parapodia. Proventricle 0.12 mm long, 0.10 mm wide, through four segments, with 19 muscle cell rows. Pharynx long, with two sinuations, located between chaetigers 1 and 8, with a large triangular pharyngeal tooth at opening of pharynx.

Distribution
Apparently cosmopolitan (San .

Notes
Specimen complete, 5.63 mm long, 0.25 mm wide, H+1051.25 mm, for 43 chaetigers. Dorsal cirri with 6-12 joints on anterior parapodia, four to seven joints and three to six joints on middle and posterior ones, respectively. Bifid simple chaetae numbering one on anterior parapodia, one to two and three to four on middle and posterior ones, respectively; subdistal tooth large, triangular on anterior chaetae, indistinct on posterior ones. Proventricle 0.65 mm long, 0.23 mm wide, through five segments, with 42 muscle cell rows. Pharynx contracted, occupying ca six segments; pharyngeal tooth not observed because of contraction of pharynx.

Notes
Specimen complete, 4 mm long, 0.20 mm wide, H+1050.90 mm, for 46 chaetigers, two transverse black lines on dorsum of each anterior chaetiger. Median antennae with seven joints, lateral ones with six joints. Peristomium with two pairs of tentacular cirri; 7-12 joints. Dorsal cirri with seven to nine joints on anterior parapodia, four to six joints and five to six joints on middle and posterior ones, respectively. Anterior falcigers numbering seven, bidentate; blades 20-30 mm long. After chaetiger 19, only characteristic ''ypsoidal'' chaetae present on parapodia, numbering two on middle region, one in posterior region; shafts of superior one ca 10 mm in diameter. Proventricle 0.48 mm long, 0.14 mm wide, occupying ca five segments, with 45 muscle cell rows. Pharynx through seven segments, with a sharp, triangular pharyngeal tooth anterodorsally. Anal cirri with six joints.

Distribution
Apparently cosmopolitan (San .

Notes
Specimen complete, 4.75 mm long, 0.32 mm wide, H+1050.82 mm, for 64 chaetigers, with a dark brownish transverse line on dorsum of each anterior parapodium, dark reddish irregular speckles on dorsum of body, and a black spot on bases of anterior and middle parapodia. Median antenna thick, with 13 joints, lateral ones with 11 joints. Tentacular cirri with 9-12 joints. Antennae and cirri with expanded subdistal or distal joints. Dorsal cirri on anterior parapodia with 12-20 joints. Anterior parapodia with 12 falcigers, strongly bidentate; blades 20-30 mm long. Posterior parapodia with 10 falcigers; superior ones finely bidentate, inferior ones unidentate, with sickle-shaped blades; shafts of inferior ones two times thicker than superior ones, with pointed, re-curved tip; blades of superior falciger 17.5 mm long, those of inferior falcigers 20 mm long. Dorsal simple chaeta from chaetiger 17, slightly recurved, indistinctly bifid. Ventral simple chaeta relatively thick, bidentate. Proventricle 0.45 mm long, 0.20 mm wide, through six segments, with 40 muscle cell rows. Pharynx through five segments, with a tooth anterodorsally.

Notes
Specimen complete, with stolon, male.

Distribution
Apparently cosmopolitan (San .