Leufroyia Monterosato, 1884

Giannuzzi-Savelli, Riccardo, Pusateri, Francesco, Prkić, Jakov, Bartolini, Stefano, Russini, Valeria, Fassio, Giulia & Oliverio, Marco, 2020, Revision of Mediterranean and NE Atlantic Raphitomidae (Gastropoda, Conoidea) 8: The genus Leufroyia Monterosato, 1884, Zoosystema 42 (22), pp. 433-473 : 438

Genus Leufroyia Monterosato, 1884

Leufroyia Monterosato, 1884: 134 .

TYPE SPECIES. — Pleurotoma leufroyi Michaud, 1828 , by subsequent designation ( Crosse 1885).

ORIGINAL DESCRIPTION. — “Gruppo ben distinto ad anfratti rigonfi, costati, spiralmente striati; bocca ingrossata internamente, levigata, senza denti nè solchi” ( Monterosato 1884: 134).

DIAGNOSIS. — Shell of medium to large size for the family, from 16 mm ( L. concinna ) to 27 mm ( L. errone a Monterosato, 1884) length, outline from suboval ( L. erronea ) to fusiform ( L. leufroyi ).

Protoconch of 2.4-3.25 whorls when multispiral, with protoconch I (embryonic shell) of 0.9-1.15 whorls, with reticulate sculpture of spirals and orthocline axial threads, and protoconch II (larval shell) of 1.4-2.2 whorls, with diagonally cancellate sculpture, sometime with weakly keeled last whorl; when paucispiral (only fossils), protoconch II (larval shell) of 1.4-2.2 whorls, with reticulate sculpture of spirals and orthocline axial threads.

Teleoconch slender, of 7 ( L. concinna ) to 8 ( L. leufroyi , L. villaria ) uniformly convex whorls, wavy axial ribs much broader than thin and numerous spiral cords. Microsculpture of dense, rather conspicuous growth lines, and extremely fine and dense microgranules, less dense, scattered or absent ( L. leufroyi ) on 1-2 adapical whorls. Whole external surface covered with relatively thick ( L. concinna , L. leufroyi ) or thin and not persistent ( L. erronea , L. villaria ) periostracum.

Inner side of outer lip smooth with no denticles. Columella simple, slightly sinuous anteriorly.

Siphonal canal from short ( L. erronea ) to moderately long ( L. leufroyi ). Siphonal notch wide, plain.

REMARKS. — The protoconch is broader (c. 500-600 µm diameter) than in the ‘multispiral’ species of Raphitoma Bellardi, 1847 and Cyrillia Kobelt, 1905 . Several Miocene and Pliocene species have a paucispiral protoconch: L. pseudoleufroyi ( Marquet, 1998: 278) , L. pseudoconcinna ( Ceulemans, Van Dingenen & Landau, 2018:113) and other still undescribed species ( Landau et al. 2020). Leufroyia differs from Raphitoma and Cyrillia also by the absence of denticles on the outer lip and by its much thinner and more numerous spiral cords.

DISTRIBUTION. — Stratigraphic distribution: the genus appears in the Middle Miocene with records from the Langhian of the Loire Basin ( France) ( Peyrot 1938; Glibert 1954). Then it is known from the Langhian-Serravallian of the Paratethys, with records from the Vienna Basin, Austria ( Hörnes 1854), Poland ( Bałuk 2003), Ukraine ( Friedberg 1912), the Karaman Basin (Serravallian Proto-Mediterranean), Turkey ( Landau et al. 2003). In the Late Miocene it has been revised in the Tortonian of the nothwestern France ( Landau et al. 2020), and it is known from the Messinian of the Loire Basin ( France) ( Brébion 1964). Then, it is continuously present throughout the Pliocene (e.g. Sacco 1904; Cipolla 1914), and the Pleistocene (e.g. Cerulli-Irelli 1910). Based on the current knowledge, the extant species of the genus are restricted to the North-East Atlantic, from the North Sea ( Norway) south to Angola, and the Mediterranean Sea.