NMITA:Neogene Marine Biota of Tropical America




Polyipnus sp.1




Specimen details:
Sample Number: PPP3055
Type Status: nontype
Scale Bar is 1 mm
Type: SEM
Orientation: mesial
Locality: Araya, Araya, Venezuela

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Morphologic Description:

    Otolith shape: posteriorly lunate, ear-like in shape;
    Thickness: moderately thick;
    Form: -Mesial slightly concave;
    Form: -Lateral very convex;
    Dorsal margin: crested and rounded;
    Dorsal margin sculpture: entire;
    Ventral margin: keeled and entire;
    Posterior margin: lunate and slightly lobed;
    Sulcus acusticus: ostial, heterosulcoid;
    Colliculum: heteromorph, a single rod-like posterior colliculum;
    Pseudocolliculum: absent;
    Ostium: floor rough, confined to the anterior dorsal part of rostrum;
    Cauda: contains the raised rod-like colliculum, margins are indistinct;
    Ostio-caudal differentiation: dorso-ventrally constricted;
    Collum: absent;
    Crista superior: absent;
    Crista inferior: absent;
    Dorsal depression: small, circular hollow below cauda, there is a second shallow depression at the base of the rostrum;
    Ventral depression: absent;
    Rostrum: narrow and pointed;
    Antirostrum: small and rounded;
    Excisura: moderate, notch shallow, angle acute;
Distribution:
    Early Pliocene: Cubagua Fm., Araya, Venezuela;


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