Pseudobiceros damawan Newman & Cannon, 1994

Velasquez, Ximena, Bolaños, D. Marcela & Benayahu, Yehuda, 2018, New records of cotylean flatworms (Platyhelminthes: Polycladida: Rhabditophora) from coastal habitats of Israel, Zootaxa 4438 (2), pp. 237-260 : 244

Pseudobiceros damawan Newman & Cannon, 1994

( Fig. 4 )

Material examined and locality: One mature specimen (35x 18 mm, live, ZMTAU-VR 25164) preserved in ethanol 70%. Collected at the Inter University Institute for Marine Sciences ( IUI), Eilat, Israel, northern Gulf of Aqaba, Red Sea (29° 30.211’ N, 34° 55.068’ E) on 18 March 2014.

Habitat: Specimen found subtidally in coral reef habitats, under rocks (2–3 m depth).

Distribution: Laing Island, Madang, Papua New Guinea (Type locality) and Heron Island, Great Barrier Reef, Australia ( Newman & Cannon 1994); Coral Bay, Australia ( Newman & Cannon 1997); Guam, Micronesia (Newman et al. 2003); Indonesia and South Africa ( Newman & Cannon 2005); Andaman, Nicobar Island, India ( Sreeraj & Raghunathan 2011); and Kusu Island, Singapore ( Bolaños et al. 2016). In this study, the specimen was found in Eilat, northern Gulf of Aqaba, Red Sea.

External morphology. Oval and elongated body with deep folds of the margin ( Fig. 4A ). Mottled whitecream background with shadows of grey towards the margin. Small white dots over the entire dorsal surface and spaced black spots of different sizes. Raised dorsal midline with shadows of grey surrounding the black spots. Presence of an orange submarginal band with a black hue in its inner area around the entire body. The orange submarginal band is interrupted by white stripes and spots. Extremely narrow black rim ( Figs. 4A, B ). The ventral side is evenly cream with the same marginal pattern as the dorsal surface ( Fig. 4C ). Squared pseudotentacles with deep lateral folds and an orange band with white spots and black rim as the rest of the body ( Fig. 4B ). Clusters of numerous pseudotentacular eyes. Round cerebral eyespot with numerous eyes ( Fig. 4B ). Thin ruffled pharynx with simple folds located anteriorly ( Fig. 4C ). Two separate male gonopores located posterior and on each side of the pharynx. Female gonopore located in the midline posterior to the male gonopores and small sucker behind the female gonopore ( Fig. 4C ).

Taxonomic remarks. Pseudobiceros damawan was recently described for Singapore by Bolaños et al. (2016) who reported a morphotype with some slight color variation compared to the specimens from Australia and India ( Newman & Cannon 1994; 1997; Sreeraj & Raghunathan 2011). Animals from Singapore exhibit a dark coloration along the inner side of the orange marginal band but the orange pigment along the midline is lacking. These features were also seen in the specimen from Israel. The same authors emended the diagnosis for this species due to its close similarity with P. murinus . However, P. murinus has a transparent rim and a white triangle between its pseudotentacles, which are both absent in P. damawan . The presence of a mottled dorsal surface varying from grey and white to light or dark brown and a conspicuous narrow black rim with an interrupted orange marginal band allowed us to identify our specimen as P. damawan . Similar colored species within the same coloring group are Pseudobiceros brogani NEWMAN & CANNON, 1997 and Pseudobiceros fulvogriseus ( HYMAN, 1959) (for detailed comparisons see taxonomic remarks for P. murinus below and Bolaños et al. 2016). P. damawan represents a new record for the Red Sea and Israel.

Figures

FIGURE 4. Pseudobiceros damawan. (A) Dorsal view, in vivo. (B) Close-up of the anterior region showing the pseudotentacles and cerebral eyes. (C) Ventral view of the live specimen showing the pharynx, sucker, and the reproductive structures. ce: cerebral eyes; fg: female gonopore; mg: male gonopore; ph: pharynx; pt: pseudotentacles; su: sucker.