Supplanaxis Thiele, 1929

Strong, Ellen E. & Bouchet, Philippe, 2020, Hidden in plain sight: two co-occurring cryptic species of Supplanaxis in the Caribbean (Cerithioidea, Planaxidae), ZooKeys 991, pp. 85-109 : 85

Genus Supplanaxis Thiele, 1929

Planaxis (Supplanaxis) Thiele, 1929. Type species: Buccinum nucleus Bruguière, 1789, by monotypy.

Planaxis (Proplanaxis) Thiele, 1929. Type species: Planaxis planicostatus G.B. Sowerby I, 1825, by monotypy (syn. nov.).

Remarks.

Thiele (1929: 203) established Supplanaxis as a subgenus of Planaxis , for planaxids with rather small, dark colored, largely smooth shells, with spiral grooves mostly on the base of the last whorl and under the suture; and with a radula characterized by a broad rachidian with two to four denticles on either side, the long lateral extensions of the lateral teeth, and the outer marginal with a very broad, finely toothed cutting edge. Based on the morphological differences in shell, radula, soft anatomy, and embryonic development, Houbrick (1987) elevated Supplanaxis to full genus.

Thiele (1929: 203) also established Proplanaxis as a new subgenus of Planaxis , with Planaxis planicostatus G.B. Sowerby I, 1825, as type species by monotypy. Houbrick (1987: 4) treated Proplanaxis as a synonym of Planaxis , but our molecular tree shows P. planicostatus to be nested within the Supplanaxis clade (see below), and not within Planaxis s.s., a taxonomic position in agreement with Laidre and Vermeij (2012), who had already used the combination Supplanaxis planicostatus . The names Supplanaxis and Proplanaxis having been published simultaneously, we act as First Revisers and, under Art. 24.2 of the ICZN Code, give precedence to the name Supplanaxis over Proplanaxis .