Odontosyllis pentalineata , Verdes, Aida, Pleijel, Fredrik & Aguado, Teresa, 2011

Verdes, Aida, Pleijel, Fredrik & Aguado, Teresa, 2011, A new species of Odontosyllis Claparède, 1863 (Annelida, Syllidae) with re-descriptions of O. liniata Hartmann-Schröder, 1962 and O. gymnocephala Hartmann-Schröder, 1965, Zootaxa 3095, pp. 27-38: 32-36

publication ID

10.5281/zenodo.201246

persistent identifier

http://treatment.plazi.org/id/D70A879C-B247-FF8A-BF94-5C5FFB726171

treatment provided by

Plazi

scientific name

Odontosyllis pentalineata
status

n. sp.

Odontosyllis pentalineata  n. sp.

( Figs. 3View FIGURE 3 A–D, 4 A–I, 5 A–F)

Material examined. USA: holotype (SIO-BIC A 2518) ( COIAbout COI GenBank accession number JF 903757View Materials), 7 paratypes (SIO-BIC A 2519, SIO-BIC A 2520, SIO-BIC A 2521,SIO-BIC A 2522, SIO-BIC A 2523). La Jollapier, California, 3252.024 ’N 11715.437 ’W; intertidal pole. 20 August 2007. Coll. F. Pleijel. La Jolla pier, California, 3252.024 ’N 11715.437 ’W; 6 m deep, intertidal pole. 21 August 2007. Coll. F. Pleijel. Off La Jolla Cove, California, 3250.713 ’N 11717.058 ’W; 12 m deep, Macrocystis  holdfast. 29 August 2007. Coll. G. Rouse. Birds Rock, La Jolla, California, 3248.367 ’N 11717.181 ’W; 18 m deep, Macrocystis  holdfast. 2 February 2010. Coll. E. Kisfaludy. Birds Rock, La Jolla, California, 3248.324 ’N 11717.107 ’W; 18 m depth, Macrocystis  holdfast. 2 February 2010. Coll. E. Kisfaludy. Off Windansea, La Jolla, California, 3250.26 ’N 11717.11 ’W; 15 m deep, Macrocystis  holdfast. 15 October 2010. Coll. G. Rouse, P. Zerofski. Off Windansea, La Jolla, California, 3250.26 ’N 11717.11 ’W; 15 m deep, Macrocystis  holdfast. 15 October 2010. Coll. G. Rouse, P. Zerofski.

Comparative material examined. Odontosyllis trilineata Imajima, 2003  . Japan: 2 paratypes (NSMT-Pol R 469) Kannonzukadashi-Aoyamadashi, Amadaiba, 3512.6 ’N 13932.4 ’E; 77–80 m deep. 20 July 1959. Coll. Biological Laboratory of the Imperial Household.

Diagnosis. Odontosyllis  with a distinct dorsal colour pattern consisting of five longitudinal black bands (medial, dorso-lateral and lateral) extending throughout body, a long pharynx with five large teeth directed backwards and two lateral plates, and compound chaetae with short bidentate, slightly spinulated blades.

Description. Holotype complete but posteriorly regenerating specimen, 15.1 mm long, 0.94 mm wide, with 71 chaetigers. Longest paratype, complete specimen, 19.2 mm long, 0.78 mm wide, with 93 chaetigers. Body shape, excluding parapodia, circular in section, ventrally flattened. Dorsum with five longitudinal black bands (medial, dorso-lateral and lateral) extending throughout body ( Figs 3View FIGURE 3 A–D, 4 A). Conspicuous ventral colour pattern consisting of three longitudinal black bands (one medial and two lateral) extending throughout body, anteriorly weaker to segments 20–22, distinct thereafter; present in holotype and one paratype, residual in another paratype. Segments with two ciliary bands extending across dorsum ( Fig. 5View FIGURE 5 A, B), and one ciliary band extending across ventral part of each parapodium ( Fig. 5View FIGURE 5 C, D). Prostomium small, wider than long, rectangular to oval, with two pairs of reddish eyes in trapezoidal arrangement, anterior pair slightly larger; eye spots absent. Median antenna inserted medially on prostomium, longer than prostomium and palps together; lateral antennae inserted near anterior prostomial margin, about half as long as median antenna. Antennae slightly articulated ( Figs 3View FIGURE 3 D, 4 A). Occipital flap pigmented, semicircular, covering posterior half of prostomium ( Figs 3View FIGURE 3 D, 4 A). Palps broad, triangular, completely separated, similar in length to prostomium. First segment shorter than subsequent ones. Tentacular cirri similar in shape to antennae; dorsal pair about twice as long as median antenna, ventral pair shorter, similar in length to median antenna. Dorsal cirri of first chaetiger longer than tentacular cirri; second, third and fourth dorsal cirri similar in length to dorsal tentacular cirri. Subsequent segments with alternating long and short dorsal cirri, long cirri about twice as long as short ones, and short cirri twice as long as parapodial lobes. Ventral cirri pillow-shaped and short, proximally inserted. Parapodia conical, with thick pre- and postchaetal lobes ( Fig. 4View FIGURE 4 B), prechaetal lobes longer than postchaetal ones. Chaetal fascicle with 10–12 compound heterogomph falcigers in midbody parapodia, shafts distally spinose ( Figs 4View FIGURE 4 C–E, 5 E, F). Compound chaetae with short bidentate blades, distal tooth larger than proximal one, blade edge with minute serrations, blades exhibiting inverse dorso-ventral gradation in length ( Fig. 4View FIGURE 4 C– E), blades about 11.3 µm in length dorsally, 20 µm in length ventrally on midbody. Parapodia with two tricuspidate aciculae ( Fig. 4View FIGURE 4 F). Pharynx long, through seven segments, surrounded by 10 papillae ( Fig. 4View FIGURE 4 G–I), with five teeth directed backwards and two lateral plates ( Fig. 4View FIGURE 4 H). Proventricle long and slender, through about 15 segments, with around 60 muscle cell rows ( Fig. 4View FIGURE 4 I). Pygidium regenerating, anal cirri absent. Paratypes with two anal cirri, similar in length and shape to dorsal cirri.

Remarks. Odontosyllis pentalineata  n. sp., is characterized by a distinct dorsal colour pattern consisting of five longitudinal black bands, long pharynx with five large teeth and two lateral plates, and compound chaetae with short bidentate blades with small spines. Odontosyllis pentalineata  n. sp., is similar to several species of Odontosyllis  with compound chaetae with short bidentate blades. This group includes O. australiensis  , O. brachydonta  , O. ctenostoma  , O. dugesiana  , O. fragilis  , O. fulgurans  , O. gravely  , O. guillermoi  , O. longigulata Perkins, 1981  ; O. luminosa  , O. phosphorea Moore, 1909  ; O. polycera  , O. setoensis  and O. trilineata  (Table 1). Odontosyllis pentalineata  differs from all these species by the number of teeth of the denticled arc, the length of the pharynx, and, especially, by the characteristic pigmentation.

The most similar species, O. trilineata  from Japan, has similar dorsal pigmentation. However, O. trilineata  has three longitudinal black bands along the body, instead of five. The compound chaetae and the morphology of the proventricle are also quite similar to those of O. pentalineata  , with the proventricle of both species extending through about 15 segments. Nevertheless, O. trilineata  differs from O. pentalineata  by having a trepan with nine pharyngeal teeth and a short pharynx extending through four segments ( Imajima, 2003), instead of five pharyngeal teeth and a long pharynx extending through seven segments. Odontosyllis gravely  (from Australia and south-east India) also has a similar pattern of pigmentation consisting of a median longitudinal black band and large lateral spots on each segment that might approach three longitudinal stripes. This species also resembles O. pentalineata  in the shape of the compound chaetae and number of pharyngeal teeth. However, they differ in that O. gravely  has long-bladed chaetae and a shorter pharynx extending through only three to four segments ( San Martín & Hutchings, 2006). Odontosyllis fragilis  (from southern California) also has dorsal pigmentation, but consisting of a dorso-median row of pigment spots along body. In addition, O. fragilis  differs from O. pentalineata  by having a shorter pharynx extending through four segments without lateral plates and lacking spinulation in blades of compound chaetae ( Kudenov & Harris, 1995). Finally, O. pentalineata  resembles O. australiensis  (from Australia) in the shape of the compound chaetae and number of pharyngeal teeth, although it has wider blades and smaller proximal teeth and its pharynx extends through seven segments instead of two. Additionally, the preserved O. australiensis  was described as yellowish, probably lacking a defined colour pattern ( San Martín & Hutchings, 2006).

Etymology. The specific epithet refers to the dorsal colour pattern of the new species, characterized by five longitudinal black bands extending along the body, one medial, two dorso-lateral and two lateral.

COI

University of Coimbra Botany Department