Flexopteron Shuto 1969

Genus Flexopteron Shuto, 1969 TYPE SPECIES. — Flexopteron philippinense Shuto, 1969, by original designation. Late Miocene: Philippines. COMMENTS The genus Flexopteron Shuto, 1969 was previously included in the subfamily Muricinae (e.g., Vokes 1992, 1996; inter alia). According to Merle et al. (2011), it displays plesiomorphic shells, differing greatly from the derived shells found in typical Muricinae that are close to the genus Murex Linnaeus, 1758. Merle et al. (2011: 54) defined an informal group called Basal muricid group including Flexopteron, Paziella, Poirieria, Timbellus, and several other genera. In a molecular phylogenetic work, Houart et al. (2021) found a clade including Flexopteron and Timbellus. This result could suggest close relationship between Flexopteron and Timbellus and confirms that they are not phylogenetically related to the derived clade of typical Muricinae. However, this relationship is not retrieved in the latest molecular phylogenetics of Russini et al. (2023), and those authors do not give subfamilial attribution to Flexopteron (incertae sedis position). Flexopteron has been considered in the past as a subgenus of Poirieria (e.g., Vokes 1992) or Paziella (e.g., Merle et al. 2011). As there is no evidence of a close phylogenetic relationship between these two genera based on molecular analyses, we give Flexopteron full generic status.