Pseudoterebellum, Maxwell & Rymer & Congdon, 2021

Maxwell, Stephen J., Rymer, Tasmin L. & Congdon, Bradley C., 2021, Resolving phylogenetic and classical nomenclature: A revision of Seraphsidae Jung, 1974 (Gastropoda: Neostromboidae), Zootaxa 4990 (3), pp. 401-453 : 432

Pseudoterebellum new genus

( Pseudoterebellinae )

Figure 8A–C

Type. Terebellum diversiornatum Eames, 1952, p. 74 , pl. 3, fig. 77.

RegNum Registration Number. 683.

Reference Phylogeny. Figure 3 .

Definition. The maximum clade consisting of Pseudoterebellum diversiornatum ( Eames, 1952) and all species that share a more recent common ancestor with it than with Seraphs sopitus ( Brander, 1766) , Paraseraphs tetanus Jung, 1974 or Terebellum terebellum ( Linnaeus, 1758) .

Diagnosis. The shell is evolute, lacking a posterior canal, and is widest near the posterior. The labrum of the shell is protocyrt. The suture is channeled. The columella is smooth.

Composition. Pseudoterebellum contains three species detailed herein, and belongs to the Pseudoterebellinae , but excludes Paraseraphs and Terebellum .

Remarks. This clade arose in the early Ypresian of the Middle East (Table 7). Members of the complex may have radiated east via the Tethys during the Ypresian into the Indonesian region of the southwestern Pacific, and contained the forebearer of the modern clade Terebellum . However, there is a significant geological discontinuity in the geological record from the period of extinction of Pseudoterebellum at the end of the Eocene, to the appearance of Terebellum during the mid-Oligocene.

Figures

FIGURE 3. The clade Seraphsidae Jung, 1974 derived from character analysis and contextualised with the fossil record showing the ancestral Seraphsinae and crown clade Pseudoterebellinae both new subfamilies.

FIGURE 8. Pseudoterebellum new genus and Terebellum Röding, 1798. A. Pseudoterebellum diversiornatum (Eames, 1952), holotype, NHMUK GG68239, length 10.1 mm (Jung 1974, pl. 14, figs. 12–14). B. Pseudoterebellum oympiae (Rolando, 2001), holotype, MGPD 28168, length 20.9 mm (Rolando 2001, fig. 2). C. Pseudoterebellum saudiensis (Abbass, 1972), holotype, ASU S53, length 25 mm (Abbass 1972, pl. V, figs. 1, 2). D. Terebellum cinctum Martin, 1916, holotype, RGM St10337, length 34.7 mm (Jung 1974, pl. 13, figs. 4, 6). E. Terebellum obtusum Sowerby, 1840, holotype, NHMUK GG21000, length 42.2 mm (Jung 1974, pl. 13, figs. 17, 18). F. Terebellum papilliferum Martin, 1916, lectotype, RGM St10339, length 28 mm (Jung 1974, pl. 13, figs. 9, 11).