Paragalene Kossmann, 1878

Castro, Peter & Ng, Peter K. L., 2008, Rhadinoplax, a new genus of Progeryonidae Števčić, 2005, for Carcinoplax microphthalmus Guinot & Richer de Forges, 1981, and a redescription of Paragalene longicrura (Nardo, 1868) (Crustacea: Decapoda: Brachyura: Goneplacoidea), Zootaxa 1777, pp. 53-68 : 62-63

Paragalene Kossmann, 1878

Paragalene Kossmann, 1879: 253 .

Type species. Paragalene neapolitana Kossmann, 1878 , by monotypy; gender feminine.

Composition. Monotypic.

Remarks. The taxonomic position of Paragalene has always been unclear. Some authors affiliate it with the Xanthidae (e.g. Nardo 1868; d’Udekem d’Acoz 1999) while others provisionally align it with the Geryonidae (e.g. Türkay 1976a, b). Manning & Holthuis (1989) did not agree that Paragalene and Progeryon should be placed in the Geryonidae and suggested that a new family may need to be established for them. Števčić (2005: 64), however, placed Paragalene in a new tribe, Paragalenini Števčić, 2005 , in the subfamily Geryoninae , Geryonidae (without any comment as usual). Karasawa & Schweitzer (2005) discussed the affinities of Paragalene with Progeryon , but while they recognised the family Progeryonidae , they postponed a decision on the position of Paragalene . Ng & Manuel-Santos (2007: 44) provisionally left it in the Progeryonidae , but in an addendum Ng & Manuel-Santos (2007: 55) briefly confirmed this when they examined specimens. Ng et al. (2008: 84) also briefly commented on the status of this genus.

The carapace of Paragalene differs from Progeryon by the strong transverse gastric and branchial ridges on the carapace, and the sharp, prominent anterolateral teeth. The first three male abdominal somites are also proportionally narrower transversely, with somites 3 and 4 fused rather than free. These differences are important at the generic but not at the family level. The condition of the male thoracic sternum, position of the press button of the male abdominal locking mechanism, structure of the male abdomen and form of the male gonopods, however, all agree very well with those of Progeryon , and we have little doubt that it should be placed in the Progeryonidae as defined here.