Imbricaria pugnaxa (Fedosov & Puillandre & Herrmann & Kantor & Oliverio & Dgebuadze & Modica & Bouchet, 2018)

pugnaxa View in CoL comb. nov., MNHN IM-2007-32124, Philippines, PANGLAO 2005 Stn CP 2378, 08°38.7′N, 123°20.1′E, 65 m. GoogleMaps

Distribution: Indo-Pacific, intertidal to bathyal depths, mostly on soft bottoms, mud, silty or well-washed sand.

Species included: Imbricaria amoena (A. Adams, 1853) 3 comb. nov., I. annulata (Reeve, 1844) 3 comb. nov., I. armonica (T. Cossignani & V. Cossignani, 2005) 3 comb. nov., I. astyagis (Dohrn, 1860) 3 comb. nov., I. bacillum (Lamarck, 1811) 3 comb. nov., I. baisei ( Poppe, Tagaro & Salisbury, 2009) 3 comb. nov., I. bantamensis (Oostingh, 1939) 1 comb. nov., I. bellulavaria (Dekkers, Herrmann, Poppe & Tagaro, 2014) 3 comb. nov., I. cernohorskyi (Rehder & Wilson, 1975) 3 comb. nov., I. cloveri (Cernohorsky, 1971) 3 comb. nov., I. conularis (Lamarck, 1811) 1, I. flammea (Quoy & Gaimard, 1833) 3 comb. nov., I. flammigera (Reeve, 1844) 1 comb. nov., I. fulgetrum (Reeve, 1844) 1 comb. nov., I. hidalgoi (G. B. Sowerby III, 1903) 3 comb. nov., I. hrdlickai (Salisbury, 1994) 1 comb. nov., I. insculpta (A. Adams, 1851) 1 comb. nov., I. interlirata (Reeve, 1844) 2 comb. nov., I. intersculpta (G. B. Sowerby II, 1870) 3 comb. nov., I. kermadecensis (Cernohorsky, 1978) 3 comb. nov., I. maui (Kay, 1979) 3 comb. nov., I. nadayaoi (Bozzetti, 1997) 3 comb. nov., I. philpoppei ( Poppe, Tagaro & Salisbury, 2009) 3 comb. nov., I. polycincta ( Turner, 2007) 3 comb. nov., I. pretiosa (Reeve, 1844) 2 comb. nov., I. pugnaxa ( Poppe, Tagaro & Salisbury, 2009) 1 comb. nov., I. rufilirata (A. Adams & Reeve, 1850) 3 comb. nov., I. ruberorbis (Dekkers, Herrmann, Poppe & Tagaro, 2014) 3 comb. nov., I. rufogyrata ( Poppe, Tagaro & Salisbury, 2009) 1 comb. nov., I. salisburyi (Drivas & Jay, 1990) 2 comb. nov., I. tahitiensis (Herrmann & Salisbury, 2012) 3 comb. nov., I. verrucosa (Reeve, 1845) 1 comb. nov., I. yagurai, (Kira, 1959) 1 comb. nov., I. zetema (Dekkers, Herrmann, Poppe & Tagaro, 2014) 3 comb. nov.

Remarks: The genus Imbricaria is, in the present classification, undergoing a dramatic rearrangement: whereas species traditionally classified in Imbricaria , like I. punctata and I. olivaeformis , that are conchologically close to I. conularis , are excluded from the genus, numerous Indo-Pacific species earlier assigned to Ziba and Subcancilla are now transferred to Imbricaria .

As circumscribed here, Imbricaria appears rather heterogeneous morphologically, with shell varying from conical to narrowly fusiform, most species having a notably higher spire than I. conularis . Shell sculpture may be faint, like in the type species, or represented by strong elevated cords, and depressions between cords are often sculptured with dense riblets. Moreover, species of Imbricaria display a remarkable disparity in radular morphology, as seen in the degree of cusp differentiation in both the rachidian and lateral teeth. In this respect, the eight studied species form a continuous grade from radulae with subequal cusps (presumably a plesiomorphic state, found in I. conularis and I. pugnaxa – see ‘Discussion’) to more derived ones with one or two cusps on each tooth greatly exceeding the others.