Acritarch excystment and surface ultrastructure, with descriptions of some Ordovician taxa

• Alfred R. Loeblich Jr. ^[2] ; Helen Tappan ^[1]
  1. [1] University of California Los Angeles

     University of California Los Angeles

     Estados Unidos

     
  2. [2] Chevron Oil Field Research Company, La Habra, California
• Localización: Revista española de micropaleontología, ISSN 0556-655X, Vol. 1, Nº. 1, 1969, págs. 45-57
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Methods of excystment of acritarchs, organic-walled microfossils of uncertain, affinities, include simple partial rupture, median splitting, development of a pylome and operculum, or an epityche (an outfolded flap formed by an elongate submarginal slit in the vesicle wall). The pseudopylome, a non-functional antapical thickening, may be mistaken for the pylome.

    Characters of excystment, surface ultrastructure, and distinctive types of processes are the bases for the new taxa Impluviculus, new genus (type species 1. milonii (Deunff), Loeblich and Tappan, new comb., from the Lower Ordovician Tremadocian of Morocco), Asketopalla, new genus (type species A. formosula Loeblich and Tappan, n. sp.), Poljancistrodorus, new genus (type species P. columbariferus Loeblich and Tappan n. sp.), and Veryhachium irroratum Loeblich and Tappan, n. sp., from the Middle Ordovician of Oklahoma, U. S. A.