Pseudobiceros hancockanus ( Collingwood, 1876 )

Bahia, Juliana & Schrödl, Michael, 2016, Pseudobiceros wirtzi sp. nov. (Polycladida: Cotylea) from Senegal with revision of valid species of the genus, Zootaxa 4097 (1), pp. 101-117 : 103

Pseudobiceros hancockanus ( Collingwood, 1876)

Taxonomic remarks. This species was subject to much confusion concerning its synonym list. It was originally described as Proceros hancockanus ( Collingwood 1876) and assigned to Prosthecereus by Lang (1884) and to Pseudoceros by Laidlaw (1903). Marcus (1950) also recognized Prosthecereus -like pseudotentacles in the drawings. Kaburaki (1923), however, synonymized it to another Collingwood (1876) species: Pseudoceros malayaensis (originally described as Stylochopsis and assigned to Pseudoceros by Bock (1913)) which has the same color pattern and color but was represented with different pseudotentacles. Bock (1913) also listed both species as synonyms, but argued that a final decision about their identity should be let open. Faubel (1984) did not include both species in Pseudoceros , Pseudobiceros, Prosthecereus or in the incertae sedis species list. Newman & Cannon (1994) treated both as synonyms; adding information from fresh material, they transferred the species to Pseudobiceros . Here we follow Newman & Cannon’s (1994) position. It is, however, necessary to revise all the species showing black background color and orange or yellow margin, using museum and fresh material.