Pseudobiceros bajae (Hyman, 1953)

Soutullo, Patricia, Cuadrado, Daniel & Noreña, Carolina, 2021, First study of the Polycladida (Rhabditophora, Platyhelminthes) from the Pacific Coast of Costa Rica, Zootaxa 4964 (2), pp. 363-381 : 373

Pseudobiceros bajae (Hyman, 1953)

( Fig. 7 )

Material examined: Five specimens sampled. Four specimens fixed for molecular and histological studies. One sagittally sectioned and stained with Azan for the Invertebrate Collections of the Museum of Natural Science ( MNCN) Madrid, Spain ..

Location: Playa Carbón Beach 10 ° 20’53.4 “N 85 ° 51’44.5” W and Playa Langosta 10 ° 17’32.2 “N 85 ° 51’12.7” W, in Las Baulas National Park of Guanacaste, Costa Rica ( Fig. 7A ); Between May 18 and 24, 2018. 73 slides: MNCN 4.01 /2503 to MNCN 4.01 /2575 .

Habitat: Low intertidal, under stones on sand and in intertidal pools under stones.

Description: External features ( Fig. 7B, C ): Elongated body shape, wavy margins, front and with rounded posterior end. Length: 38 mm. Pseudotentacles ear-shaped. Ebony black dorsal colouration uniformly dotted with small white dots. There is an unpigmented region around the pseudotentacles on which a cerebral eye cluster is located. Ventrally pigment is less. Pharynx ruffled in the first half of the body.

Reproductive system ( Fig. 7E, D, F ): Two male copulatory organs, both formed by an elongated seminal vesicle; oval, muscular prostatic vesicle ( Fig. 7E, D ); without stylet, but reinforced ductus ejaculatorius and elongated, ciliated atrium ( Fig. 7F ).

Female reproductive system formed by a vagina externa and an underdeveloped vagina that curve towards the posterior end ( Fig. 7F ).

Distribution: Pseudobiceros baJae has been reported from the Mexican Pacific; Puerto Peñasco, Miramar and Bahia de la Paz (Hyman 1953) and now from Costa Rica in this study.

Figures

FIGURE 7. Pseudobiceros bajae (Hyman, 1953). A. Distribution map and sample points; B. Ventral view of whole live animal; C. Whole live animal, dorsal view; D-E. Histological sections of the copulatory organs stained with Azan; F. Sagittal reconstruction of the reproduction system (D, E, F anterior end to the left).