NMITA:Neogene Marine Biota of Tropical America




Equetus sp.1 (n.sp)




Specimen details:
Sample Number: PPP04
Type Status: nontype
Scale Bar is 1 mm
Type: SEM
Orientation: mesial
Locality: Canal, Canal, Panama

- Enlarge Image -

Morphologic Description:

    Otolith shape: discoid to circular;
    Posterior margin: rounded and slightly irregular;
    Ventral margin: completely rounded and slightly irregular;
    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: long and narrow, strongly bent in ventral direction. The tip curves in the anterior direction. The area situated between the posterior part of the ostial crista inferior and the recurved portion of the cauda is much wider than the maximal diameter of the;
    Ostium: circular and small;
    Pseudocolliculum: absent;
    Colliculum: heteromorph, low anterior and indistinct posterior colliculi;
    Excisura: narrow, notch absent;
    Antirostrum: very short and rounded;
    Rostrum: reduced;
    Ventral depression: absent;
    Dorsal depression: shallow and elongate;
    Sulcus acusticus: ostial, heterosulcoid;
    Thickness: moderately thick;
    Form: -Lateral convex;
    Dorsal margin: slightly rounded and irregular, slightly expanded anteriorly;
    Dorsal margin sculpture: slightly irregular;
    Form: -Mesial slightly convex;
Distribution:
    Middle Miocene to Late Miocene: Gatun Fm., Canal, Panama;


Return to: