Carditoidea, Ferussac, 1822

Superfamily Carditoidea View in CoL Family Carditidae

Genus Warrana Laseron, 1953

Warrana culmen Simone, Medeiros & Molozzi , new species ( Fig. 56 View Figure 56 A-G) https://zoobank.org/ B3A7914F-EFA4-4E19-B1DA-7C25C8FFA67F

Types: Holotype 166644. Paratype: MZSP 163737, 3 spm, from type locality.

Type locality: BRAZIL. Paraíba ; Cabedelo,off, 07°02′41″S 34°47′42″W, ~ 14 m [C. R. Medeiros col., 2022] GoogleMaps .

Diagnosis: NE Brazilian species with umbonal angle of ~70°; height ~1.2× longer than wide. Umbonal transverse fold narrow.Hinge occupying ~21% of shell height. Crenulation in shell edges minute and numerous.

Description: Shell relatively thick; walls slightly translucent; outline oval, ~1.2× taller than long. Color white. Umbo central, blunt, with both sides straight, relatively symmetrical (anterior edge slightly shorter), with angle ~70°; ventral edge widely rounded ( Fig. 56 View Figure 56 A-D, F). Prodissoconch smooth, bulging, occupying ~5% of shell height, ~14% of shell width, of 207 µm; flanked by narrow transverse umbonal fold ( Fig. 56F, G View Figure 56 ). Sculpture uniform, concentric cords from transverse umbonal fold up to shell edge, interspaces deep, equivalent to half each cord width. Hinge thick, occupying ~21% of shell height, bearing only cardinal tooth, and wide anterior resilifer. Resilifer as simple, transverse groove, twice longer than wide, ligament circular in section, locater only in its dorsal, sub-umbonal region ( Fig. 56F, G View Figure 56 ). Hinge teeth in posterior hinge half. Left valve with large anterior cardinal tooth, rather triangular, 3-times taller than long slightly bifid ventrally; posteriorly flanked by similar-sized socket ( Fig. 56C, F, G View Figure 56 ). Right valve with tooth-socked counterpart ( Fig. 56D View Figure 56 ). Inner surface glossy, with muscular scars of difficult visualization ( Fig. 56C, D, F View Figure 56 ); scar of anterior and posterior adductor muscles relatively small, round- ed, located in both sides of umbonal slopes; pallial line simple. Shell inner edge possessing minute crenulations in its entire ventral border ( Fig. 56F View Figure 56 ).

Etymology: The specific epithet has the origin the Latin word culmen , meaning summit; an allusion to angulation of the shell apex (umbo), a species′ characteristics.

Distribution: From Maranhão to Alagoas, Brazil.