Lepidonotus carinulatus Grube, 1869

De Assis, Jose Eriberto, de Brito, Rafael Justino, Christoffersen, Martin Lindsey & de Souza, Jose Roberto Botelho, 2015, A catalogue of the scaleworm genus Lepidonotus (Polynoidae, Polychaeta) from South America, with two new records for Brazilian waters, ZooKeys 533, pp. 63-98 : 67

5. Lepidonotus carinulatus Grube, 1869 Figures 2, 3

Polynoe (Lepidonotus) carinulata - Grube 1869; Grube 1878: 26-27, pl. 3: figs 2-2 b.

Lepidonotus carinulatus .- Willey 1905: 248-249, pl. 1: figs 7-11, Fauvel 1911: fig. 1, 1918, 1919a, Augener 1922: figures 3-3b, Seidler 1923, Fauvel 1933, Wesenberg-Lund 1949, Fauvel 1955, Mohammad 1971, Day 1975: figs 2 g-k, Amoureux et al. 1978, Hanley and Burke 1991: fig 20, Imajima 1997: figs 45-46, Rasheed and Mustaquim 2003: figs 7-8, Barnich et al. 2004.

Lepidonotus tenuisetosus . - Mohammad 1971: 288, Gravier 1902.

Diagnosis.

With two nuchal nodules and without nuchal folds; black pigmentation on antennae, cirrophores and tentaculophores; elytra with dark pigmentation; elytral surface reticulate, with oval to rounded macro- and microtubercles, anterior ones flattened, smooth or carinate, central and posterolateral ones warty; margin with fringing papillae; neurochaetae bidentate.

Description.

Body elongated, flattened dorsoventrally, subrectangular in cross-section; 2 mm in length, including palps and pygidial cirri; 26 chaetigerous segments, and pygidium (Figure 2a-b). Prostomium bilobed, rounded to hexagonal, lateral antenna with terminal insertion (Figure 3a). Two pairs of eyes; anterior pair dorsolateral, near widest portion of prostomium, posterior pair near posterior end of prostomium, converging towards midline, buccal segment without nuchal fold, but with pair of nuchal nodules (Figure 3a-b). Median and lateral antennae, tentacular and dorsal cirri with two dark rings (Figure 2a), both having subdistal swelling, culminating abruptly in sharp point; ceratophores cylindrical, median antenna larger than lateral antennae. Pair of palps, slightly smaller than median antenna, culminating in thin point, with 8 longitudinal rows of papillae.

Tentacular segment with two pairs of cylindrical tentaculophores, with three prostomial chaetae on anterodorsal bases. Buccal cirri larger than ventral cirri, with cylindrical cirrophores. Pharynx with nine pairs of papillae and two pairs of maxillae. Facial tubercle present. Dorsal cirri with same coloration as median antenna, larger than ventral cirri, with cylindrical cirrophores.

Parapodia biramous (Figure 3b), prechaetal lobe quadrate or subtriangular, postchaetal lobe short and subtriangular, both with acicula; short notopodia on anterodorsal side of neuropodia. Notochaetae spinous, superior row slender, serrated on convex side (Figure 3c). Neuropodia large, truncate, distally cleft with prechaetal lobe slightly longer than poschaetal lobe. Neurochaetae stouter than notochaetae, falcate, subdistally thickened, with several rows of spines, distal spines usually much larger than basal ones, and bidentate tips with small secondary tooth (Figure 3d).

Twelve pairs of elytra, covering dorsum entirely, with dark-brown pigmentation; pairs until last chaetiger segment following order: 2, 4, 5, 7, 9, 11, 13, 15, 17, 19, 21 and 23; long papillae along external edge. First three pairs of elytrae more ornate, with tubercles (Figure 3e); on 11th and 12th pair with ornamentation similar to that in first pair. Most carinate macrotubercles in central region (Figure 3f-g), surrounded by microtubercles (Figure 3h); after 4th or 5th pair (Figure 3i), small warty tubercles give impression of smooth elytra (Figure 3j).

Nephridial papillae starting from chaetiger 7, with peduncular aspect. Short ventral cirri with thin tip; pair of long anal cirri with same coloration as median antenna; dorsal anus in last chaetiger segment (Figure 2b).

Habitat.

Recorded between the intertidal and 60 m; elsewhere reported down to 200 m ( Hartmann-Schröder and Hartmann 1991, Wehe 2006).

Syntype.

ZMB 1071.

Type locality.

Bohol, Philippines.

Distribution.

Red Sea, Arabian Sea: Socotra Archipelago, Gulf of Oman, Arabian Gulf. Elsewhere: Indo-West Pacific: Madagascar, Sri Lanka, Indonesia, Philippines, Hong Kong, South China Sea, Australia, New Caledonia, Japan ( Willey 1905, Fauvel 1953, Hanley and Burke 1991, Hanley 1992, Imajima 1997, Barnich et al. 2004).

New records: Coast of Paraíba, Brazil: Pedra da Galé, Pitimbú (07°28'17"S, 34°47'26"W), POLY- UFPB 1501; Rio Mamanguape (06°48'44"S, 34°54'48"W), POLY- UFPB 1502, 1503.

Remarks.

Zenetos et al. (2010) assigned Lepidonotus carinulatus as an exotic species with an origin in the Indo-Pacific/Red Sea. Its establishment success in the Mediterranean is questionable, because its description, based on local specimens, was insufficient. It is an exotic species in Brazilian waters with casual establishment success; because only the present records are known, it is presumed to be non-established in the Mediterranean area ( Zenetos et al. 2010).