Mioawateria
Vella (1954) originally introduced Mioawateria as a subgenus of Awateria Suter, 1917, with Awateria (Mioawateria) personata Powell, 1942, as the type species. According to its describer, the subgenus Mioawateria is characterized by the presence of strongly shouldered whorls and a narrow moniliform subsutural fold. Powell (1966) provided a list of species, all from the New Zealand Tertiary, he regarded as characteristic of Mioawateria and referred both Awateria and Mioawateria to subfamily Borsoniinae. Beu (1969) used Mioawateria as a full genus and transferred it to the Raphitominae on the basis of the presence of diagonally cancellate protoconch sculpture. Maxwell (1988) widely discussed the classification of New Zealand fossil Mioawateria species and recognized the following three fossil species: M. personata (Powell, 1942), M. expalliata (Laws, 1947) and M. aitanga Grant-Mackie and Chapman-Smith, 1971, this latter characterized by strong spiral sculpture and possibly belonging to a distinct lineage (P.A. Maxwell pers. comm.). Fischer (1927) described Mangilia (Pleurotomella) extensaeformis var. crasselirata from the Pliocene of Timor which seems to represent a valid species with a relatively well developed spiral sculpture. Maxwell (1988) also recognized the recent Pleurotomella extensaeformis Schepman, 1913, a species with a broad Indo-Pacific distribution (Okutani, 1968; Sysoev, 1996; Thiele, 1925), as a recent member of the genus. According to Appeltans et al., 2012 (World Register of Marine Species, accessed at http://www.marinespecies.org) Mioawateria is represented in the recent fauna by five species.
A possible sixth species is Gymnobela rhomboidea Thiele, 1925 reported by Sysoev (1997) as a Mioawateria. Recently, Figueira & Absalão (2012) referred Pleurotoma (Bela) blakeana extensa Dall, 1881, Pleurotomella (Gymnobela?) malmii Dall, 1889 and Clathurella watsoni Dautzenberg, 1889 to genus Magnella. The authors claimed that the synonymy of Magnella with Mioawateria is unwarranted as the holotype of Mioawateria personata (Powell, 1942), type species of Mioawateria, has a broken and eroded protoconch. We have examined specimens of M. personata from the Waiauan (Middle Miocene) of Karoro quarry, Greymouth (New Zealand)studied by Maxwell (1988) and stored at the Institute of Geological and Nuclear Sciences (GNS accession number GS3341, J32/f7585) which bear a typical raphitomine protoconch (fig. 2.D–E). These specimens conform in all teleoconch features to the holotype of Mioawateria personata (GNS accession number TM 3761), from the Opoitian (Early Pliocene) of Mangawhero Stream, Wairoa (New Zealand) (fig. 2.A–C). Even assuming the remote hypothesis that M. personata actually had a paucispiral protoconch, its inclusion within the family Raphitomidae would not be excluded as demonstrated by numerous raphitomine species, such members of Taranis, bearing this type of protoconch. For these reasons we agree with Maxwell’s proposed synonymy and regard the species cited above as members of Mioawateria.