Odontosifllis longiseta. New Species 



K inure 4(1:-]. 



OdontosyUis n. sp. Day, Field, and Montgomery, 

 1971: 121. 



Holotupv.—VSNM 43120; 100+ paratypes, 

 USNM 43121. 



Dencriptiou. — Numerous specimens obtained 

 but all broken. Complete specimen probably 

 15-20 mm long by 1.5 mm wide for 60-70 seg- 

 ments. Body stout, strongly arched dorsally 

 but flattened ventrally. No color pattern and 

 whole worm uniformly flesh pink in alcohol. 

 Prostomium (Figure 4g) much broader than 

 long and separated from tentacular segment 

 by a deep groove. Palps broad and flattened, 

 fused basally and bent ventrally. Two pairs of 

 large red eyes, three rather short antennae, and 

 a pair of curved nuchal ridges almost encircling 

 posterior pair of eyes. Tentacular segment very 

 short and fused dorsally to setiger 1, the large 

 circular occipital flap appearing to arise from 

 the latter. Two pairs of tentacular cirri slightly 

 longer than antennae. Mouth with well defined 

 lateral lips; buccal cavity with an internal dor- 

 sal projection at entrance to pharynx. Pharynx 

 short, broad and strongly chitinized with a ven- 

 tral arc of six recurved teeth and a cutting 

 plate on either side (Figure 4h). Pharynx ex- 

 tending from setiger 8 to 10 and followed by a 

 long muscular proventriculus with 60 rows of 

 points extending from setiger 10 to 18. 



Antennae, tentacular cirri, and dorsal cirri 

 all smooth, tapered, and relatively short. An- 

 terior dorsal cirri barely three-quarters seg- 

 mental breadth, those of middle segments alter- 

 nately longer and equal to half segmental 

 breadth or shorter and equal to one third seg- 

 mental breadth. Parapodia (Figure 4i) with 

 setigerous lobes stout and obviously bilabiate 

 with the setae issuing from a slit; ventral cirri 

 stout with pointed tips. Setae (Figure 4j) all 

 compound, with shaft-heads well serrated and 

 blades unusually long and strongly bidentate; 

 secondary tooth as large as apical one. No simple 

 setae even in posterior feet. 



Remarks. — As noted earlier, the buccal cavity 

 has an internal dorsal ridge which extends back 

 and becomes a digitiform lobe at the entrance 

 of the pharynx. A similar structure was noted 

 by Day (1967) in Odontosyllis polycera (Schmar- 



da) and Pharyngeovalvata natalensh Day. Both 

 also possess an occipital flap so that the two 

 genera are related although Pliarynf/eovalvata 

 lacks chitinous teeth. 



In Od(>)itosyllis lo)igiscta the occipital flap 

 appears to arise from the first setiger but this is 

 due to the fact that the dorsal part of the ten- 

 tacular segment is fused to the first setiger. 

 In other species, where these two segments are 

 separate, the occipital flap definitely arises from 

 the tentacular segment. 



0. lonqiseta is easily distinguished by the 

 long, strongly bidentate blades of the setae, 

 short dorsal cirri and the large occipital flap. 

 In O. fitlgiDxuis Claparede, recorded by Petti- 

 bone (1963a) from New England, the setal blades 

 are short, the dorsal cirri are about equal to 

 the segmental breadth and the occipital flap is 

 small. In O. ctoiostuma Claparede, (). polycera 

 (Schmarda), and O. dugesia)ia Claparede the 

 setal blades are all short; in O. gibba Claparede 

 the blades are long but unidentate. 



R( cords. — Common off Beaufort in 20-200 m 

 (21 *). 



Eusyllis lamelligera 

 Marion and Bobretzky, 1875 



Eusyllis lamelligera. - Fauvel, 1923: 294, Fig. 

 113 a-e. - Pettibone, 1963a: 120, Fig. 33, 

 34a-d. 



Records. — North Carolina in 7 m (3, 17). 



Distribution. — North Atlantic from Massa- 

 chusetts to North Carolina and the English 

 Channel to Spain; Mediterranean; 7-37 m. 



Parapionosyllis longicinata 

 (Webster and Benedict. 1884) 



Pioiiosyllis miuiita. - Fauvel, 1923: 292, Fig. 



lllf. 

 Parapionosyllis lotigicirrata. - Pettibone, 1963a: 



132, Fig. 35 e, f. 



Ri cords. — Thirteen specimens in 10-20 m off 

 Beaufort (21, *). 



Distrihutio)!. — Massachusetts; Mediterran- 

 ean; intertidal to 20 m. 



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