NMITA:Neogene Marine Biota of Tropical America

Nebris sp.1 (n.sp)

Specimen details:
Sample Number: PPP1149
Type Status: type
Scale Bar is 1 mm
Type: SEM
Orientation: mesial
Locality: Darien, Darien, Panama

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Morphologic Description:

    Otolith shape: oblong;
    Thickness: very thick;
    Form: -Mesial convex;
    Form: -Lateral convex, with nodules or tubercles;
    Dorsal margin: slightly flat, with a truncate prominence in the middle part of the rim; the anterior and posterior parts of this margin are straight and inclined;
    Dorsal margin sculpture: slightly irregular;
    Ventral margin: slightly rounded;
    Posterior margin: slightly S-shaped, ventrally fro9m a large post-ventral dome;
    Sulcus acusticus: ostial, heterosulcoid;
    Colliculum: heteromorph, low anterior and indistinct posterior colliculi;
    Pseudocolliculum: absent;
    Ostium: ovate and very large, ostial crista superior widely separated from the dorsal margin; the anterior tip of the ostium doesn't reach the anterior margin, except by a rudimentary canal.;
    Cauda: large, deep, strongly bent in ventral direction and clearly separated in a narrow horizontal and deeply incised and expanded vertical section by an intra-caudal crest;
    Ostio-caudal differentiation: dorso-ventrally constricted;
    Collum: absent;
    Crista superior: poorly developed over ostium, ridge-like over cauda;
    Crista inferior: poorly developed under ostium, moderately well developed under cauda;
    Dorsal depression: shallow and elongate;
    Ventral depression: absent;
    Rostrum: reduced;
    Antirostrum: rounded;
    Excisura: narrow, notch absent;
    Late Miocene: Tuira Fm., Darien, Panama;

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