Pseudoceros bimarginatus Meixner, 1907

Marquina, Daniel, Aguado, M. Teresa & Noreña, Carolina, 2015, New records of Cotylea (Polycladida, Platyhelminthes) from Lizard Island, Great Barrier Reef, Australia, with remarks on the distribution of the Pseudoceros Lang, 1884 and Pseudobiceros Faubel, 1984 species of the Indo-Pacific Marine Region, Zootaxa 4019 (1), pp. 354-377 : 356

Pseudoceros bimarginatus Meixner, 1907

( Fig. 1 )

Pseudoceros bimarginatum Meixner, 1907: 168 –170.— Marcus 1950: 84.

Pseudoceros corallophilus Hyman, 1954: 223 –224, fig. 2.— Coleman 1990: 31; Cannon & Newman 1994b: 83, fig. 4.

Material examined. AM W.44682, MI QLD 2400, sagitally sectioned.

Description. Elongated body 17 mm long, 9 mm wide. Cerebral eyes horseshoe-shaped. Dorsal colouration: ivory white background, a mid-dorsal bright white line; three marginal bands (inner to outer): orange, black and a yellow rim ( Fig. 1 A). Sucker and genital pores, all at the same distance. Seminal vesicle large and rounded, ventrodorsally oriented. Spherical prostatic vesicle with a narrow and short duct. Penis papilla, forwards oriented, with a conic stylet. Stylet wide, housed in a very deep male atrium ( Fig. 1 B, C, E). Female genital complex ( Fig. 1 D, E) with the characteristic configuration of the genus.

Remarks. Pseudoceros bimarginatus , P. contrarius Newman & Cannon 1995 , P. intermittus Newman & Cannon, 1995 , and P. confusus Newman & Cannon, 1995 share a similar colour pattern ( Newman & Cannon 1995) and coexist on the reefs of Eastern Australia. The characteristic order or the marginal bands (orange-black-yellow) distinguish P. bimarginatus from the other three species mentioned. Newman & Cannon (1994b) noticed that most specimens possess a bright white mid-dorsal line and an extra marginal band inner to the orange one of the same colour, though these lines may be occasionally faint or absent; in the examined specimen the mid-dorsal line is present, but the marginal one is absent.

Distribution. Previously found in the Gulf of Tadjourrah, Somalia ( Meixner 1907), Djibouti ( Gosliner et al. 1996), Heron Island, Australia, and Anilao, Philippines ( Newman & Cannon 1994b), Kwajalein, Marshall Islands ( Newman & Cannon 1998). First report for Lizard Island.

Figures

FIGURE 1. Pseudoceros bimarginatus Meixner, 1907, AM W. 44682, MI QLD 2400. A. Live specimen; B – D. Histological sections of the reproductive system; E. Sagittal reconstruction of the reproductive system, anterior to the left in B – E. Abbreviations: cg = cement glands, cp = cement pouch, fa = female atrium, i = intestine, ma = male atrium, p = pharynx, pv = prostatic vesicle, s = stylet, sv = seminal vesicle, va = vagina, vd = vas deferens.