Gailleagrassor, Harzhauser & Landau, 2024

Harzhauser, Mathias & Landau, Bernard M., 2024, The Colubrariidae, Eosiphonidae, Melongenidae, Pisaniidae, Prodotiidae and Tudiclidae (Gastropoda, Buccinoidea) of the Miocene Paratethys Sea, Zootaxa 5427 (1), pp. 1-110 : 20

Gailleagrassor nov. gen.

Type species. Gailleagrassor paratethyca nov. sp.; Middle Miocene , Austria .

Diagnosis. Moderately large, elongate fusiform shell with cancellate sculpture on early teleoconch whorls, abapically sculpture of prominent narrow, flat spiral cords, typically with one weaker secondary intercalated between primaries.

Description. As for type species.

Etymology. Combination of Gaillea and Calagrassor , referring to the intermediate position of the new genus.

Included species. Only the type species is known.

Stratigraphic and geographic range. Badenian/Langhian (Middle Miocene), Central Paratethys Sea.

Paleoenvironment. Unknown; probably middle to outer neritic environments.

Discussion. Gailleagrassor is reminiscent of Calagrassor and Gaillea Kantor, Puillandre, Fraussen, Fedosov & Bouchet, 2013 [type species Eosipho coriolis Bouchet & Warén, 1986 ; present-day, Philippines]. The strongly differentiated sculpture of primary and secondary spiral cords distinguishes Gailleagrassor from Calagrassor , which has spiral cords of equal size ( Fraussen & Stahlschmidt 2016b). All extant Gaillea species differ from the fossil Paratethyan species in their broader, ovoid shape and they lack broad, flat spiral cords. Moreover, all Indo-West Pacific Gaillea species are characterized by an angulate shoulder, differing clearly from Gailleagrassor . In contrast, the Caribbean Buccinum canetae Clench & Aguayo, 1944 , which is currently placed in Gaillea (e.g., Fraussen & Stahlschmidt 2016b), has rounded whorls like the Paratethyan species. No molecular data are available to prove the placement of the Caribbean species in Gaillea and based on the different morphology, we suspect, that ‘ Gaillea’ canetae ( Clench & Aguayo, 1944) might turn out to belong to a different genus. Indeed, ‘ Gaillea ’ canetae could be closer related to Gailleagrassor paratethyca than the IWP species of Gaillea . Nevertheless, the two species are unlikely to be congeneric because the Caribbean species differs in its relatively broader shell, the narrower spiral cords, and the presence of fold-like opisthocyrt axial ribs (see Fraussen & Stahlschmidt 2016b; figs 74–75).