Parathyone, Deichmann, 1957

Martins, Luciana & Tavares, Marcos, 2021, A new species of Parathyone (Holothuroidea: Dendrochirotida: Cucumariidae) from northeastern Brazil, with a key to species, Zootaxa 4985 (2), pp. 245-252 : 251

Key to the Parathyone species

1. Anterior process of the calcareous ring radial plate as long as the base of the radial plate................. P. braziliensis

- Anterior process of the calcareous ring radial plate distinctly longer than the base of radial plate...................... 2

2. Body wall buttons strongly knobbed with rounded knobs ( Fig. 4 d–f ); one Polian vesicle; longitudinal muscle splitting off before midlength of body cavity.............................................................. P. surinamensis

- Body wall buttons slightly knobbed with triangular knobs ( Fig. 4 a–c ); two Polian vesicle; longitudinal muscle splitting off after midlength of body cavity...................................................... Parathyone itapuaensis sp. nov.

Figures

FIGURE 4. Morphological comparisons between (a–c) knobbed buttons from Parathyone itapuaensis sp. nov., holotype (MZUSP 2089) and (d–f) Parathyone surinamensis (USNM E27248).