NMITA:Neogene Marine Biota of Tropical America



Neopisthopterus sp.1



Specimen details:
 Sample Number: PPP2676
Type Status: nontype
Scale Bar is 1 mm
Type: SEM
Orientation: mesial
Locality: San Jose River, San Jose River, Trinidad

- Enlarge Image -

Morphologic Description:

    Otolith shape: slightly square, becoming oval;
    Thickness: moderately thin;
    Form: -Mesial slightly convex;
    Form: -Lateral slightly convex;
    Dorsal margin: approximately straight, angled to rostrum;
    Dorsal margin sculpture: irregular;
    Ventral margin: gently rounded, dentate in middle;
    Posterior margin: slightly rounded to flat and irregular;
    Sulcus acusticus: ostial, heterosulcoid;
    Colliculum: homomorph, very low, indistinct anterior colliculum;
    Pseudocolliculum: absent;
    Ostium: oblong to fusiform;
    Cauda: short, oval, poorly defined posteriorly;
    Ostio-caudal differentiation: dorso-ventrally constricted;
    Collum: absent;
    Crista superior: ridge-like and curved over the cauda, poor over ostium, absent at tip;
    Crista inferior: ridge-like and curved under the cauda, well developed under ostium;
    Dorsal depression: shallow or absent;
    Ventral depression: absent;
    Rostrum: short and pointed;
    Antirostrum: small and pointed;
    Excisura: moderately wide, notch shallow, angle acute;
Distribution:
    Middle Miocene: Manzanilla Fm., San Jose River, Trinidad;

Return to: