Baseodiscus delineatus (Delle Chiaje, 1825)

(Figure 2 [3])

Polia delineata ? Delle Chiaje, 1825: 427, pl. XXVIII, fig. 4.

Borlasia striata Quoy & Gaimard, 1833: 286, pl. 24, figs 3, 4.

Borlasia carmelina Quatrefages, 1846: 196 .

Polia curta Hubrecht, 1879: 209 .

Eupolia ascophora Bürger, 1890: 24, pl. II, fig. 27, pl. IX, fig. 184.

Eupolia marmorata Bürger, 1890: 24, pl. I, fig. 11, pl. II, fig. 26, pl. V, fig. 73.

Eupolia amboinensis Staub,1900: 78, pl. XLVII, fig. 1, 1b, pl. XLVIII, figs1–5.

Eupolia reticulata? Staub, 1900: 78, pl. XLVII, figs 3, 4, pl.XLVIII, figs 6–9.

Baseodiscus insignis Punnet & Cooper, 1909: 5 pl. 1, figs 1a, b.

Baseodiscus curtus (Hubrecht, 1879): Bürger, 1904: 82; Stiasny-Wijnhoff, 1920: 102, fig. 2 a–e; Kajihara, 2007:303.

Baseodiscus delineatus var. curta (Hubrecht, 1879): Bürger, 1895: 601, pl. 3–5, 7, 9, 17, pl.19 fig. 6; Stiasny-Wijnhoff, 1920: 102, pl. 5, fig. 2 a–e; Corrêa, 1956: 199, pl. 2, figs 6–11; Corrêa, 1958: 443, pl. 1 figs 1–2; Corrêa, 1961: 11, fig. 7; Corrêa, 1963: 42; Kajihara, 2007: 293.

Baseodiscus delineatus (Delle Chiaje, 1825): Diesing, 1850: 243; Bürger, 1904: 82; Stiasny-Wijnhoff, 1920:102; Coe, 1940: 260; Coe, 1947: 105; Coe, 1951: 179, fig. 24, fig. 25 a, b; Gibson, 1974: 355, figs 1–7; Gibson & Winsor, 1980: 173; Riser, 1991: 436; Vernet & Anadon, 1991: 92; Gibson, 1995: 478; Hochberg & Lunianski, 1998: 294; Gibson & Sundberg, 2001: 1260, tab. 1; Strand et al. 2005: 3785, figs 1, 2; McDermott, 2006: 1009; Kajihara, 2007: 303; Lyimo et al. 2008: 45; Wirtz, 2009: 46; Magarlamov & Chernyshev, 2011: 440, pl. 1, figs a–e, pl. 2 figs a–f.

Material examined. One specimen (41 mm), MZUSP 0 0 0 0 9, Brazil, Ceará, Caucaia, Praia de Dois Coqueiros, 3°41.28’ S 38°36.55’ W, under rock, coll. Yan Timbó, 18. VI.2011.

One specimen (66 mm), MZUSP 0 0 0 10, Brazil, Ceará, Caucaia, Praia do Pacheco, 3°41.11' S 38°37.91' W, under rock, coll. Cecili Mendes, 18.VI.2011.

Diagnosis. Body long, not fragile; with irregular, interrupted orange and white longitudinal stripes, from head to tail; stripes can vary from light orange to red. Cephalic lobe (head) rounded, delimited posteriorly by neck-like constriction. Several ocelli along anterolateral margins of head. Mouth ventral, immediately posterior to cephalic lobe. Posterior extremity rounded, without caudal cirrus.

Distribution. Western Atlantic: Curaçao (Corrêa 1963); Europe (Spain and Italy), Cape Verde, Bermuda, Barbados, USA (Florida), and Puerto Rico (Gibson 1995); Belize (Collin et al. 2005); Brazil (São Paulo, Bahia [Gibson 1995] and Ceará [present study]).

Eastern Pacific: USA (Gulf of California) and Chile (Coe 1940).

Western Pacific: Fiji Island, Mariana Island, Java Island, Torres Strait, Australia (Great Barrier Reef) and Japan (Gibson 1995).

Indian: Java Island, Australia, Mauritius Islands and Zanzibar (Gibson 1995).

Adriatic Sea and Mediterranean Sea (Gibson, 1995, Kajihara 2007).

Ecology. Specimens in this study were littoral, under rocks. This species is reported from littoral and sublittoral zones to depths of 50 m or more, in various bottom types, under rocks and boulders on coarse clean to shelly or muddy sand, in crevices of rocks, on seagrass or algae, among sponges or other encrusting or colonial organism and corals (Gibson 1995).

Remarks. This is one of the more widespread species of Nemertea, being recorded in both hemispheres, in tropical and subtropical waters, and extending to temperate latitudes (Gibson 1995).

Taxonomic confusion is frequent, due to the wide geographical distribution, variability of color (bands can vary from orange, brown or green), many synonyms (especially Baseodiscus curtus and B. jonasii) and several changes in genus name. The disjunct distribution of this species and seemingly associated variation in color pattern may indicate a species complex and a need for a taxonomic revision of the taxon.