Pseudobiceros wirtzi Bahia & Schrödl, 2016, sp. nov.
Creators: name: Bahia, Juliana
name: Schrödl, Michael
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Platyhelminthes
Rhabditophora
Polycladida
Pseudocerotidae
Pseudobiceros
Pseudobiceros wirtzi

description: Pseudobiceros wirtzi sp. nov.
Figures 1 and 2
Type material. Holotype: One specimen 21 x 16 mm collected October 2009 at Senegal, near Ngor Island (Voucher ZSM 20160015HT).
Paratypes: Two specimens in 96% ethanol collected 14.10.2009 at Santo Antão, Cape Verde (Voucher ZSM 20160016PT)
Geographic distribution. Senegal and Cape Verde. Additional photographic records from Madeira (17.03.2009, photo cortesy prof. Dr. Peter Wirtz) and Canarias Islands (Vera et al. 2008).
Etymology. The species is named after Prof. Dr. Peter Wirtz, who provided the material and has contributed with numerous marine invertebrate field guides over the years.
Diagnosis. Black to very dark brown background color with narrow yellow lines, some of them partly white, mostly on their tips. Thin lines scattered on dorsal surface, without distinctive orientation; most transverse but not straight, curving and some even splitting.
Description. Color: Black to very dark brown background color. Narrow yellow lines, some of them partly white, mostly on their tips. Thin lines scattered on dorsal surface, without distinctive orientation; most transverse but not straight, curving and some even splitting. In Senegal specimen lines white when nearer to margin; in Madeira worms, yellow lines and all white lines in middle of body (Fig. 1 A, C).
Form: body rounded, delicate constitution, ruffled margin.
Pseudotentacles: pointed ear-like, about 2 mm long (Fig. 1 C, Fig. 2 A).
Eyes: cerebral eyespots arranged in horseshoe shape cluster of approximately 18 eyespots. Deep dark coloration and contracted pseudotentacular area making eyespots counting difficult. Ventral pseudotentacular eyespots in four groups, two in sinus between folds, and other two on each broad flap of marginal tentacles (Fig. 1 A). Dorsally, two groups with evenly spaced eyespots in broader part of pointed ear-like tentacle, and two groups, one in each pseudotentacular tips (Fig. 1 A). These more densely arranged as in main pseudotentacle structure.
Digestive system: mouth opens at 4 mm from anterior margin, pharynx short with 4 to 5 shallow folds, 1.7 mm long (Fig. 1 B).
Body wall: sucker 1 mm in diameter, located at 1.2 mm from female gonopore. Ventrally, epidermis almost twice as thick as basement membrane, densely ciliated. Muscular layers thin, outer longitudinal, followed inward by circular and inner diagonal.
Gonopores: two male and one female gonopores. Male pores 0.5 mm in diameter at 5.5 mm from anterior margin; female pore 1 mm behind male gonopore, 6 mm in diameter (Fig. 1 B).
Male reproductive system: seminal vesicle large and elongated, 0.5 mm long and 0.3 mm broad. Prostatic vesicle rounded and 0.19 mm in diameter (Fig. 2 B, C, D). Ejaculatory duct straight, 0.2 mm long. Male atrium shallow, penis papillae 0.25 long and stylet short.
Female reproductive system: specimen seems to be immature, since we have not found in our slides female structures, like cement glands, vagina and uteri.
Taxonomic remarks. The presence of two male gonopores, smooth dorsal surface, simple and shallow folded pharynx and complex folded pseudotentacles place the new species in the genus Pseudobiceros. Pseudocerotidae species with black background and yellow and white lines color pattern are not common. Pseudoceros zebra generally resembles the studied species in its color pattern (Rüppell & Leuckart 1828), but, they belong to different genera. Pseudoceros zebra present the complex ruffled pharynx typical for Pseudoceros, while Pseudobiceros wirtzi sp. nov. has few simple folds in its pharynx. In addition, the newly described species lacks a marginal band and exhibits a dorsal surface with thin yellow and white transverse and multiple lines in multiple directions, mostly transverse, instead of the lack of pigmentation between black areas showed by Pseudoceros zebra.
In Marcus’ (1950), Faubel’s (1984), and Newman & Cannon’s (1994) revisions of accepted Pseudoceros and Pseudobiceros species, no other Pseudobiceros species match the color pattern presented by P. wirtzi. Newman & Cannon pointed out species with transverse lines pattern such as Pseudobiceros bedfordi, P. dendricticus, P. flavolineatus, P. fulgor, but all present a distinctive margin, which is lacking in our specimens. Pseudobiceros bedfordi, (Laidlaw 1903a) has a much more complex color pattern with wider stripes instead of lines, and with blotches, mottling, and different colored dots that are absent from P. wirtzi. Pseudobiceros dendricticus, has yellow background color and brown longitudinal lines and a yellow median line (Prudhoe 1989), instead of black background color and yellow and white lines as the studied specimens. Pseudobiceros flavolineatus (Prudhoe 1989) is the one that most resembles P. wirtzi, but it presents a double row of dark spots on its margin, has a reddish brown background color and the narrow yellow lines are disposed from the median line to the margin without touching each other, in a concentric design, which is not the case in P. wirtzi. The Australian species P. fulgor (Newman & Cannon 1994) has white stripes instead of yellow and a lighter background color of brownish orange or deep pink, and presents yellow or cream blotches and black margin that are absent in P. wirtzi, in addition to a rounded seminal vesicle instead of elongated. The studied specimens belong to the same species as the ones illustrated in Pérez Sanchéz & Moreno Batet (1990, p: 101), Wirtz & Debelius (2003, p: 84) and Newman & Cannon (2003, p: 84). It was also recently reported, but not described, as Pseudocerotidae sp4 from Canary Islands by Vera et al. (2008).
description: Published as part of Bahia, Juliana & Schrödl, Michael, 2016, Pseudobiceros wirtzi sp. nov. (Polycladida: Cotylea) from Senegal with revision of valid species of the genus, pp. 101-117 in Zootaxa 4097 (1) on pages 105-108, DOI: 10.11646/zootaxa.4097.1.5, http://zenodo.org/record/267125