Description of a new Gibberula species (Volutoidea: Cystiscidae) from eastern Florida

A new Gibberula species is described from eastern Florida as G. redferni n. sp., and it is compared with closely related species from the Caribbean, Senegal, the Mediterranean Sea, Oman and New Caledonia. The variability of both its shell morphology and its animal chromatism is displayed. Gibberula redferni is proposed to belong to the species group of G. ubitaensis Espinosa & Ortea, 2000, as defined by McCleery (2009). The possible occurrence of an old Tethyan radiation is discussed, as well as different aspects of the phenetic variability occurring in the G. ubitaensis species group