|Daughter taxa: (blue => in age window 0-800Ma)|
Original description: Diagnosis.– Heterohelicidae with test wall flexure on the lateral sides of the test, resulting in carinate appearance.
Description.– Test is biserial throughout. Chambers are globular to subrectangular in lateral view, increasing gradually and moderately in size as added. Sutures are distinct and depressed, straight to slightly oblique to the test axis of growth. Periphery is subacute due to the development of a test wall flexure, which results in the duplication of the test wall in the periphery region. Aperture is arch-shaped, situated at the base of the last formed chamber. Two small and symmetrical periapertural flanges, rimmed or not, border the aperture on the lateral sides. Apical part can be smooth. Pustulose periapertural area is present above the aperture. Chamber surface ornamented with costae, which can be parallel to the periphery, longitudi- nal or oblique to the test axis of growth. Ornamentation thickenings can be present on the earlier chambers in the proximity of the central ‘zigzag’ suture. Test wall calcareous, hyaline perforate; pores can be simple, or situated in the center of a crater-like structure in the evolved species.
Entries in the Catalog of original descriptions: Hendersonia, Hendersonites
Distinguishing features: Biserial throughout, test compressed with a carinate peripheral margin
Last occurrence (top): within Campanian Stage (72.05-83.64Ma, top in Campanian stage). Data source: Total of range of species in this database
First occurrence (base): within Coniacian Stage (86.26-89.77Ma, base in Coniacian stage). Data source: Total of range of species in this database
Plot of occurrence data:
Dec 2017 - Plotting of Neptune data has been re-enabled on the Mesozoic pages following revision of the age-models in Neptune. The data is, however, still very sparse for the Early Cretaceous
Hendersonites compiled by the pforams@mikrotax project team viewed: 20-9-2020
Short stable page link: http://mikrotax.org/pforams/index.php?id=110279 Go to Archive.is to create a permanent copy of this page - citation notes