NMITA:Neogene Marine Biota of Tropical America

Ophioscion aff. simulus (Gilbert, 1898)

Specimen details:
Sample Number: PPP2667
Type Status: nontype
Scale Bar is 1 mm
Type: SEM
Orientation: mesial
Locality: Manzanilla Bay, Manzanilla Bay, Trinidad

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Morphologic Description:

    Otolith shape: rhomboidal;
    Thickness: thick;
    Form: -Mesial convex;
    Form: -Lateral convex;
    Dorsal margin: slightly rounded;
    Dorsal margin sculpture: distinctly pointed pre-dorsal spine following by rustic post-dorsal angle;
    Ventral margin: flattened and entire;
    Posterior margin: rounded, with a prominent dome dorsally, emarginated ventrally;
    Sulcus acusticus: ostial, heterosulcoid;
    Colliculum: heteromorph, low anterior and indistinct posterior colliculi;
    Pseudocolliculum: absent;
    Ostium: approximately square;
    Cauda: deep and wide, the anterior portion is oblique and separated from the vertical portion by an intra-caudal crest;
    Ostio-caudal differentiation: dorso-ventrally constricted;
    Collum: absent;
    Crista superior: poorly developed over ostium, ridge-like over anterior portion of the cauda;
    Crista inferior: poorly developed under ostium, well developed under cauda;
    Dorsal depression: very narrow and elongate;
    Ventral depression: absent;
    Rostrum: reduced;
    Antirostrum: sharply pointed;
    Excisura: moderately wide, notch absent;
    Middle Miocene: Manzanilla Fm., Manzanilla Bay, Trinidad;

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