Steromphala Gray, 1847

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 : 57-58

Genus Steromphala Gray, 1847

Type species. Trochus cinerarius Linnaeus, 1758 , OD ( Gray 1847: 146). Present-day, NE Atlantic, North Sea. Not in the Mediterranean Sea except punctal (and unsuccessful) man-made introductions (pers comm. S. Gofas 2020).

Diagnosis. Subtriangular shell shape, usually broader than high, often with broad cyrtoconoid spire outline; shoulder angulation weak to absent or close to adapical suture; periphery convex or with basal angulation. Base flat to convex. Umbilicus open, partly with umbilical atrium; only rarely more or less sealed. Sculpture comprising fine ridges and striae but no nodes or cusps (see also Affenzeller et al. 20 17).

Remarks. The species which nest in the Steromphala clade (Uribe et al. 2017a) display a wide morphological disparity. Therefore, the generic placement of extinct species is difficult. Herein, the genus is restricted to species with broad, cyrtoconoid shells (“ cineraria -morphotype”; e.g. brocchii Mayer in Cocconi, 1873 ) and species with broad shells with marked basal angulation (“ rarilineata -morphotype; e.g. dertosulcata Sacco, 1896 ).

The oldest but doubtful record of this genus comes from the early Miocene of the Proto-Mediterranean Sea. Reliable records date back at least to the late Miocene in the NE Atlantic and the Proto-Mediterranean Sea. The fossil record of extant species starts not before the early Pliocene.

= Adriaria Pallary, 1917 ; type species: Trochus albidus Gmelin, 1791 , OD (Pallary 1917: 145), Present-day: Mediterranean Sea.

= Colliculus Monterosato, 1888; type species: Trochus adansonii Payraudeau, 1826 , SD (Sacco 1896: 37). Present-day, Mediterranean Sea .

The status of Colliculus is not fully resolved because Uribe et al. (2017a) did not include the type species Trochus adansonii into their analysis. Based on the data of Barco et al. (2013), however, Uribe et al. (2017a) discussed a placement in their clade 1. As this clade includes also the type species of Steromphala , it is most likely that Colliculus is a junior synonym of Steromphala . This clade 1 includes G. umbilicaris , G. cineraria , G. pennanti and G. racketti . G. spratti , G. nivosa , and G. nebulos a might also belong in this clade (Uribe et al. 2017a).

= Gibbulastra Monterosato, 1884; type species: Trochus divaricatus Linnaeus, 1758 , SD ( Crosse 1885: 440). Present-day: Mediterranean Sea.

= Korenia Friele, 1877 ; type species: Trochus cinerarius Linnaeus, 1758 , OD ( Friele, 1877: 305). Present-day, NE Atlantic, North Sea.

= Phorculellus Sacco, 1896 (replacement name for Phorculus Monterosato, 1888 , which is a junior homonym of Phorculus Cossmann, 1888 ); type species: Trochus varius Linnaeus, 1758 ; OD (Sacco 1896: 35). Present-day, Mediterranean Sea.

= Phorculorbis Cossmann, 1918 (nomen nudum): Phorculorbis is used by Cossmann (1918: 226) as section of Gibbula (Gibbula) in a table on Gibbulinae systematics. On page 229 Cossmann (1918) clarifies, that this name was proposed by Monterosato as unpublished name (“in schedis”) for the Pliocene Trochus brocchii Mayer [= Steromphala brocchii (Mayer in Cocconi, 1873) ]. From the context it does not seem that Cossmann (1918) wanted to establish Phorculorbis as valid taxon.

= Scrobiculinus Monterosato, 1889; type species: Trochus strigosus Gmelin, 1791 [= Steromphala cineraria ( Linnaeus, 1758) ], by monotypy. Present-day, NE Atlantic, North Sea.

= Spraticulus Nordsieck, 1982; type species Trochus spratti Forbes, 1844 , OD (Nordsieck 1982: 33). Present-day, eastern Mediterranean Sea. Introduced as “Sektion” (= section) of Gibbula (Colliculus) , 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).

= Strigosella Sacco, 1896; type species: Trochus strigosus Gmelin, 1791 [= Steromphala cineraria ( Linnaeus, 1758) ], OD Sacco (1896: 49). Present-day, Mediterranean Sea, NE Atlantic, North Sea.

= Tumidulus Nordsieck, 1982, type species Trochus tumidus Montagu, 1803 , OD (Nordsieck 1982: 29). Present-day, NE Atlantic. Introduced as “Sektion” (= section) of Gibbula (Steromphala) , 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).

= Tumulus Monterosato, 1888 ; type species: Trochus umbilicaris Linnaeus, 1758 , SD (Sacco 1896: 35), Present-day: Mediterranean Sea .

= Varulus F. Nordsieck, 1977 (nov. nom pro Phorculus Monterosato, 1888 (non Cossmann, 1888); junior objective synonym of Phorculellus Sacco, 1896, Present-day: Mediterranean Sea