Record details

Title
    New observations and interpretations of the enigmatic poorly know Late Paleozoic Irregularina Bykova, 1955
Author
    Hladil, Jindřich
    Nose, M.
    Schlagintweit, F.
Language
    anglicky
Publication type
    článek v odborném periodiku
Source title - serial
    Acta Palaeontologica Romaniae
Vol./nr.
    Roč. 9, č. 1
Pages
    s. 3-22
Year
    2013
Notes
    Rozsah: 20 s. : E
Subject category
    cryptoendoliths
    incertae sedis
    Parathuramminida
    protozoa
    psammobionts
Keyword
    1955
    Bykova
    Enigmatic
    Interpretations
    Irregularina
    Know
    Late
    New
    Observations
    Paleozoic
    Poorly
Abstract (in english)
   Specimens of the enigmatic poorly known taxon Irregularina Bykova, usually classified as a parathuramminid foraminifer, occur in great abundances irregularly distributed within fine-grained wacke-/packstones, partly pressing against bioclasts. The aggregation of their numerous and variously shaped sparite-filled bodies within the sediment may resemble abiogenic fenestral fabrics. It is suggested that these organisms were sediment-dwelling (psammobiontic) forms being capable of stretching into sediment interstices. In Amphipora wackestones, Irregularina settles on amphiporids skeletons and cryptoendolithically penetrates the latter by completely mimicing the labyrinthic canal system. Given the wide range of intraspecific variation by adaptation of the dynamic shape, the high species diversity of Irregularina based on differences in morphology and size is challenged.
   The irregular shape with finger-like extensions interpreted as moveable pseudopodia (lobopodia) and the supposed ability to change the shape requires a primarily not calcified, flexible outer body membrane. Therefore Irregularina shares some similarities with modern giant amoeboid heterotrophic protists that may also exhibit a psammobiontic way of life. Another cross-reference is given to homeomorphic representatives of Mesozoic thaumatoporellaceans. The true biogenic nature of Irregularina, however, is still unsolved.
Contributor
    AV ČR Brno, Geologický ústav
Contributor code
    AV ČR, GLÚ
Source format
    U
Import date
    23. 10. 2014