Pericelis cata Marcus & Marcus 1968

Bahia, Juliana, Padula, Vinicius, Lavrado, Helena Passeri & Quiroga, Sigmer, 2014, Taxonomy of Cotylea (Platyhelminthes: Polycladida) from Cabo Frio, southeastern Brazil, with the description of a new species, Zootaxa 3873 (5), pp. 495-525 : 497-499

Pericelis cata Marcus & Marcus 1968

( Fig. 2 )

Material examined. One specimen (MNRJ-PLAT 24, 23 x 22 mm) as sagittal sections of reproductive structures (23 slides), rest of the animal in ethanol 70%. Collected 0 3.08.2008 at Enseada do Mimi, Ilha do Papagaio, Cabo Frio, Brazil (22°53'30.85"S; 41°59'9.52"W). Depth: 6 m.

Distribution. This species was recorded from Curaçao (type locality; Marcus & Marcus 1968), Colombian Caribbean ( Quiroga et al. 2004b), Cabo Frio ( Bahia & Padula 2009) and Bahia, Brazil ( Queiroz et al. 2013). At Cabo Frio P. c a t a seems to occur only at the sublittoral, as no specimen was found at the intertidal zone, but instead at 6 to 10 m depth, and only at Ilha do Papagaio.

Diagnosis. Pattern of coloration mottled with dark beige coloration combined with black spots; marginal tentacles distant from each other; marginal, pre-cerebral and cerebral eyespots present; cerebral eyespots in two elongated rows, not clearly separated in the middle. Seminal vesicle very muscularized and developed; male atrium shallow and uterine duct with muscular sphincter.

Description. External characters as described in Bahia & Padula (2009).

Epidermis and body wall: Ventral epidermis 66 µm tall and dorsal epidermis 44 µm tall. Body wall with external longitudinal muscular layer and internal diagonal muscular layer. Rhabdites are observed both dorsally and ventrally.

Gonopores: Male and female gonopore closely together at 22 mm from the anterior margin. Pores open independently ( Fig. 2 B).

Male reproductive system: Testicles ventral. Penis papillae (0.5 mm) muscular and directed backwards as the rest of the male structures ( Fig. 2 B). Seminal vesicle rounded and well developed (1.5 x 1.3 mm), male atrium shallow ( Fig. 2 B). Ejaculatory duct filled with sperm and granules of eosinophylic secretion.

Female reproductive system: Ovaries dorsally disposed. Uterine duct epithelium tall ( Fig. 2 D). Uterine ducts separated from vagina by a muscular sphincter ( Fig. 2 D). Vagina directed backwards ( Fig. 2 B and D), 410 µm long, with folds at the epithelium and cement pouch present ( Fig. 2 D).

Taxonomic remarks. We found larger specimens (from 23 x 22 mm to 45 x 34 mm) than those observed in the original description (from 27 x 21 mm to 33 x 21 mm), but external morphological and anatomical differences were not found. Other species in this genus ( P. bayerleyana , P. orbicularis , P. hymanae ) do not present a sphincter in the uterine duct and seminal vesicle as large as P. c a t a ( Marcus & Marcus 1968), or present a deeper male atrium ( Meixner 1907; Hyman 1953; Poulter 1975), and cerebral eyespot clusters clearly separated ( Hyman 1953).

Ecology. One specimen of Pericelis cata was, during one collection, placed in the same container with a nudibranch specimen of Felimare lajensis (Troncoso, Garcia & Urgorri 1998) . When they were released, P. c a t a was “wounded” (a rip in the median part of the body) and there were only pieces of gonad and epithelial tissue from F. lajensis ( Fig. 2 C). No contact was observed between these species in the field, but P. c a t a may have chemical compounds that match or exceed the ones present in F. lajensis , such as furodisine lactone, obtained from its dysideid sponge prey ( Pereira et al. 2012).

Figures

FIGURE 2. Pericelis cata (MNRJ-PLAT 24). A. in vivo dorsal view; B. sagittal section of male reproductive structures; C. P. cata and Felimare lajensis; D. sagittal section of female reproductive structures. cg: cement glands; cv: sperm containing vesicle; ma: male atrium; nu: nudibranch; pa: penis papilla; pl: polyclad; pt: pseudotentacles; sf: sphincter; sv: seminal vesicle; va: vagina.