Gibbula Risso, 1826

Harzhauser, Mathias, 2021, The Cainozoic to present-day record of Circum-Mediterranean, NE Atlantic and North Sea Cantharidinae and Trochinae (Trochoidea, Gastropoda) - a synopsis, Zootaxa 4902 (1), pp. 1-81 : 22-23

Genus Gibbula Risso, 1826

Type species. Trochus magus Linnaeus, 1758 , SD ( Herrmannsen 1847: 473). Present-day, Mediterranean Sea.

Diagnosis. Broad trochiform shells, usually broader than high; teleoconch whorls frequently with shoulder and basal angulations. Base moderately convex to flat. Sculpture comprising prominent spiral cords. Axial sculpture developed by most species ranging from broad axial ribs, swellings or nodes on upper part of whorls to delicate prosocline growth lines raised between spiral cords. Umbilicus deep, wide to moderately wide. A narrow umbilical atrium may be present.

Remarks. The diagnosis above is based only on the species, which nest together in the molecular analysis of Uribe et al. (2017a): Gibbula ardens , G. fanulum , G. guttadauri , G. magus , G. philberti and G. turbinoides . In this group, only G. turbinoides is somewhat atypical due to its more turbiniform outline and delicate axial growth lines.

The diagnosis would have to be widened if nearly smooth shells with convex whorls are included, as represented by Gibbula drepanensis and G. vimontiae . Molecular data, however, are missing so far for these species for which Puteolus Monterosato, 1888 would be available as genus name.

Nevertheless, the morphology of Gibbula sensu stricto suggests that many fossil species attributed to Gibbula in the literature have to be placed in other genera. The “typical” morphotype with blunt axial swellings as represented by the type species can be traced back for sure to the early Miocene (e.g. G. puschii , G. sagus ). It seems to be represented already during the Lutetian by the NE Atlantic Gibbula bourdoti Cossmann, 1902 . An even older record would be Gibbula (Enida) janoscheki Traub, 1984 , from the Paleocene of Austria, but this species should be placed in Calliostomatidae .

= Forskalena Iredale, 1918; type species: Trochus fanulum Gmelin, 1791 , OD ( Iredale 1918: 28). Present-day, Mediterranean Sea. In the phylogenetic tree of Uribe et al. (2017a), Gibbula fanulum , the type species of Forskalena plots in the same clade as Gibbula magus , the type species of Gibbula Risso, 1826 . Therefore, Forskalena is a junior synonym of Gibbula .

= Forskaliopsis Coen, 1930; type species: Gibbula (Forskaliopsis) bellinii Coen, 1930 [= Gibbula magus ( Linnaeus, 1758) ], OD ( Coen 1930: 2). Present-day, Mediterranean Sea.

= Gibbuloidella Sacco, 1896; type species: Gibbula (Gibbuloidella) divergens Sacco, 1896 , OD (Sacco 1896: 38). Pliocene, Mediterranean Sea.

= Glomulus Monterosato, 1888 ; type species: Trochus turbinoides Deshayes, 1835 , SD (Sacco 1896: 38). Present-day, Mediterranean Sea. Glossulus is an incorrect subsequent spelling by Pallary (1938).

= Magulus Monterosato, 1888 ; type species: Trochus ardens Salis Marschlins, 1793 , SD (Sacco 1896: 43). Present-day, Mediterranean Sea. In the phylogenetic tree of Uribe et al. (2017a), Gibbula ardens , the type species of Magulus , plots in the same clade as Gibbula magus , the type species of Gibbula Risso, 1826 . Therefore, Magulus is a junior synonym of Gibbula .

= Puteolus Monterosato, 1888; type species Trochus drepanensis Brugnone, 1873 , SD (Nordsieck 1982: 31). Present-day: Mediterranean Sea, NE Atlantic. Cossmann & Peyrot (1917: 266) and Cossmann (1918: 238) considered Puteolus to be preoccupied by Puteolus Lowe, without giving a date or reference. This opinion is based on a dubious record in the Nomenclator Zoologicus of Marschall (1873: 135), who lists “Puteolus Lowe” with question mark. Marschall (1873) gives no reference and Puteolus Lowe is a nomen nudum.

= Spurculus Nordsieck, 1982, type species Trochus spurcus Gould, 1856 , OD (Nordsieck 1982: 26). Presentday, NE Atlantic. Introduced as “Sektion” (= section) of Gibbula (Gibbulastra) , which makes it an available name according to ICZN Article 10.4. ( A uninominal name proposed for a genus-group division of a genus, even if proposed for a secondary (or further) subdivision, is deemed to be a subgeneric name even if the division is denoted by a term such as “section” or “division).

= Stomatulus Nordsieck, 1982; type species Gibbula ibizenca Nordsieck, 1982 , OD (Nordsieck 1982: 31). Present day, Balearic Islands. Introduced as “Sektion” (= section) of Gibbula (Puteolus) , which makes it an available name according to ICZN Article 10.4. ( A uninominal name proposed for a genus-group division of a genus, even if proposed for a secondary (or further) subdivision, is deemed to be a subgeneric name even if the division is denoted by a term such as “section” or “division”).