NMITA:Neogene Marine Biota of Tropical America



Larimus aff. breviceps (Cuvier, 1830)



Specimen details:
 Sample Number: PPP2675
Type Status: nontype
Scale Bar is 1 mm
Type: SEM
Orientation: mesial
Locality: San Jose River, San Jose River, Trinidad

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Morphologic Description:

    Otolith shape: rhomboidal to fan-shaped;
    Ventral margin: rounded, entire and emarginated posteriorly;
    Sulcus acusticus: ostial, heterosulcoid;
    Posterior margin: straight and oblique;
    Dorsal depression: shallow and elongate;
    Crista inferior: poorly developed under ostium, moderately well developed along sulcus;
    Crista superior: poorly developed over ostium, ridge-like over horizontal portion of the cauda;
    Collum: absent;
    Ostio-caudal differentiation: dorso-ventrally constricted;
    Cauda: narrow horizontal portions continue with short and expanded vertical portion strongly flexed in acute angle;
    Ostium: enlarged, inclined, and with a typical notch in the ostial crista superior; inferior crista anterior widely separated from the anterior margin of the sagitta, and does not reach the margin except by extremely contracted canal The ventral margin of the os;
    Pseudocolliculum: absent;
    Excisura: absent, notch absent;
    Antirostrum: rounded;
    Rostrum: short and reduced;
    Ventral depression: shallow and elongate near the ventral margin;
    Colliculum: heteromorph, low anterior and indistinct posterior colliculi;
    Dorsal margin sculpture: entire;
    Thickness: very thick;
    Form: -Mesial convex;
    Dorsal margin: slightly straight;
    Form: -Lateral convex;
Distribution:
    Middle Miocene: Manzanilla Fm., San Jose River, Trinidad;

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