Carinomella cf. lactea Coe, 1905

Mendes, Cecili B., Matthews-Cascon, Helena & Norenburg, Jon L., 2016, New records of ribbon worms (Nemertea) from Ceará, Northeast Brazil, Zootaxa 4061 (2), pp. 146-156 : 149

Carinomella cf. lactea Coe, 1905

( Figure 2 [2a–2b])

Carinomella lactea: Coe, 1905: 127 , Pl. 5, figs. 45–49, Pl. 6, figs. 50–54, Pl. 7, figs. 55, 56, Pl. 8,

figs. 57, 58, Pl. 9, figs. 59–61, Pl. 10, figs. 63–65, Pl. 11, figs. 66–62; Boesch, 1973: 230; Turbeville & Ruppert, 1983: 103; Fox & Ruppert, 1985: 37; Norenburg, 1993: 212; Hochberg & Lunianski, 1998: 295; Ritger & Norenburg, 2006: 941; Turbeville, 2006: 968, figs. 4, 5, 6c; Chernyshev, 2010: 2288.

Material examined. One specimen (26 mm), MZUSP 0 0 0 12, Brazil, Ceará, Paracuru, Praia da Pedra Rachada, 3°23.95' S 39°0.85' W, on mud sand, coll. Cecili Mendes, 16. VI.2014.

Field diagnosis. Body small, rounded anteriorly, flattened intestinal region; translucent, whitish anteriorly and yellowish-orange posteriorly. No eye spots, white dorsomedian line on head. Large mouth, immediately posterior to cerebral ganglia. Alimentary canal divided into two portions, anterior clear and less opaque than yellowish intestinal region, as seen by Coe (1905). Lateral organs present posterior to start of intestine; circular orange band formed in this region after preservation.

Distribution. Western Atlantic: USA (Florida [ Corrêa 1961], South Carolina [ Fox & Ruppert 1985] and Virginia [ Boesch 1973]) and Brazil (Ceará [present study])

Eastern Pacific: USA (California [ Coe, 1905])

Ecology. The present specimen was found in muddy sand, under rocks in the lower intertidal zone, which agrees with Coe (1905). However, Corrêa (1961) reports a specimen dredged from about 4 m in Biscayne Bay.

Remarks. This species can be confused with Carinoma mutabilis because of the ground color, but C. mutabilis lacks lateral sense organs. Identification of the present specimens remains uncertain because there are few internal and external characters that can be compared with other species. A firmer identification awaits genetic study. A factor favouring the probability that this is conspecific with worms reported as C. lactea from Florida is the significant taxonomic overlap among nemerteans from Florida and Brazil. However, given the lack of morphological diagnostics, the identity for all Atlantic reports of this species must be held in doubt until compared with northeastern Pacific Ocean specimens from the vicinity of the type locale.

Figures

FIGURE 2. (1) Tubulanus rhabdotus Corrêa, 1955, lateral view; (2) Carinomella cf. lactea Coe, 1905: (a) head, dorsal view; (b) posterior end, lateral view; (3) Baseodiscus delineatus (Delle-Chiaje, 1825): dorsal view; (4) Cerebratulus cf. lineolatus Coe, 1905, dorsal view; (5) Cerebratulus sp. 1: (a) dorsal view; (b) posterior end, dorsal view; (6) Cerebratulus sp. 2: (a) whole body, dorsal view; (b) head, ventral view; (7) Lineid sp. 1: (a) head, dorsal view; (b) posterior end, dorsal view. Scale bars: 1, 2 a, 2 b, 6 b and 7 a, 1 mm; 3, 5 a, 5 b and 6 a, 5 mm; 4 and 7 b, 10 mm.