Resolving phylogenetic and classical nomenclature: A revision of Seraphsidae Jung, 1974 (Gastropoda: Neostromboidae) Author Maxwell, Stephen J. 0000-0002-4328-6171 College of Science and Engineering, James Cook University, P. O. Box 6811, Cairns, Queensland 4870, Australia. & Stephen. maxwell @ my. jcu. edu. au; https: // orcid. org / 0000 - 0002 - 4328 - 6171 tephen.maxwell@my.jcu.edu.au Author Rymer, Tasmin L. 0000-0002-9963-6345 College of Science and Engineering, James Cook University, P. O. Box 6811, Cairns, Queensland 4870, Australia. & Centre for Tropical Environmental and Sustainability Sciences, James Cook University, P. O. Box 6811, Cairns, Queensland 4870, Australia. & Tamsin. rymer @ jcu. edu. au; https: // orcid. org / 0000 - 0002 - 9963 - 6345 amsin.rymer@jcu.edu.au Author Congdon, Bradley C. 0000-0002-8751-0892 College of Science and Engineering, James Cook University, P. O. Box 6811, Cairns, Queensland 4870, Australia. & Centre for Tropical Environmental and Sustainability Sciences, James Cook University, P. O. Box 6811, Cairns, Queensland 4870, Australia. & brad. congdon @ jcu. edu. au; https: // orcid. org / 0000 - 0002 - 8751 - 0892 brad.congdon@jcu.edu.au text Zootaxa 2021 2021-06-22 4990 3 401 453 journal article 5563 10.11646/zootaxa.4990.3.1 6a6dd89d-6b74-47ed-ba8e-71b526355b69 1175-5326 5026777 70610FEE-4497-4804-817C-CEC2D66DDBFE Diameza Deshayes, 1865 [Maxwell, this paper] nomen cladi conversum ( Seraphsinae ) Figure 6A 1865 Diameza Deshayes , p. 572. Cossmann 1889 , p. 95 . Jung 1974 , p. 32 . Bandel 2007 , p. 138 . Caze et al. 2010 , p. 426 . Type . Ovula fragilis Defrance, 1825 , p. 132 (by monotypy). RegNum Registration Number. 678. Reference Phylogeny. Figure 3 . Definition. The maximum clade consisting of Diameza fragilis ( Defrance, 1825 ) and all species that share a more recent common ancestor with it than with Seraphs sopitus ( Brander, 1766 ) , Miniseraphs eratoides ( Cossmann, 1889 ) or Terebellum terebellum ( Linnaeus, 1758 ) . Diagnosis. The shell is involute and inflated. The maximum diameter of the shell is just above the midline of height. The parietal callus is weak. The labrum is thickened and sinuous, being protocyrt on the lower part of the shell, and opisthocyrt on the upper part. The labrum extends above the apex, and there is a rudimentary basal sinus. The shell is smooth, with a few indistinct basal oblique grooves. The columella is smooth, and mostly straight near the base. Composition. Diameza contains one species detailed herein, and belongs to the Seraphsinae , but excludes Miniseraphs and Seraphs . Remarks. There is only one recognised member of Diameza . While closely related to Miniseraphs , the latter lacks the acute apex of Diameza . However, based on overall similarities, it is likely they both share a hitherto unknown common ancestor arising in the Thanetian, Palaeocene of Europe ( Jung 1974 ). While originally placed with Ovulidae Fleming , Diameza shows the rudimentary stromboidal notch and growth pattern more consistent with the Seraphsidae ( Cossmann 1904 ; Jung 1974 ). The clade Diameza Deshayes, 1865 has a restricted geological range of the Middle Eocene of Europe (Table 3).