pforams@mikrotax - Riveroinella pforams@mikrotax - Riveroinella


Classification: pf_cenozoic -> Guembelitrioidea -> Cassigerinellidae -> Riveroinella
Sister taxa: Cassigerinella, Riveroinella
Daughter taxa (time control age-window is: 0-800Ma)
Riveroinella martinezpicoi


Citation: Riveroinella Bermúdez & Seiglie 1967
taxonomic rank: genus
Type species: Riveroinella martinezpicoi Bermúdez & Seiglie 1967
Taxonomic discussion: Included in Cassigerinella by Premoli Silva and Spezzaferri (1990) and Spezzaferri (1994) but regarded as a discrete short-ranging monospecific genus by Pearson et al. 2018

Catalog entries: Riveroinella

Distinguishing features:
Parent taxon (Cassigerinellidae): Coiled biserial
This taxon: Like Cassigerinella but with a peculiar slit-like aperture surrounded by a protruding, flange-like lip and strongly acute profile

NB These concise distinguishing features statements are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus.
They are being edited as the site is developed and comments on them are especially welcome.


Biogeography and Palaeobiology

Most likely ancestor: Cassigerinella - at confidence level 4 (out of 5). Data source: We follow Loeblich and Tappan (1988) and suggest that Riveroinella was descended from Cassigerinella some time in the lower Miocene [ v p.490] .

Biostratigraphic distribution

Geological Range:
Last occurrence (top): at top of M5b subzone (100% up, 15.1Ma, in Langhian stage). Data source: Total of ranges of the species in this database
First occurrence (base): within M5b subzone (15.10-16.27Ma, base in Burdigalian stage). Data source: Total of ranges of species in this database

Plot of occurrence data:


Bermudez, P. J. & Seiglie, G. A. (1967). A new genus and species of foraminifer from the Early Miocene of Puerto Rico. Tulane Studies in Geology. 5(3): 177-199. gs

Loeblich, A. R. & Tappan, H. (1988). Foraminiferal Genera and Their Classification (Volume I-II). Van Nostrand Reinhold Co., New York. 1-1059. gs

Premoli Silva, I. & Spezzaferri, S. (1990). Paleogene planktonic foraminifer biostratigraphy and paleoenvironmental remarks on paleogene sediments from Indian Ocean sites, Leg 115. Proceedings of the Ocean Drilling Program, Scientific Results. 115: 277-314. gs

Spezzaferri, S. (1994). Planktonic foraminiferal biostratigraphy and taxonomy of the Oligocene and lower Miocene in the oceanic record. An overview. Palaeontographia Italica. 81: 1-187. gs

Missing or ambiguous references: Pearson et al. 2018;


Riveroinella compiled by the pforams@mikrotax project team viewed: 24-5-2024

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