Catalog - Hastigerina parapelagica Catalog - Hastigerina parapelagica

CATALOG OF ORIGINAL DESCRIPTIONS: Hastigerina parapelagica Saito & Thompson, in Saito et al. 1976

This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.


Higher levels: pf_cat -> H -> Hastigerina -> Hastigerina parapelagica
Other pages this level: H. aspera digitata, H. digitata, H. eocenica, H. klampisensis, H. murrayi, H. parapelagica, H. primitiva

Hastigerina parapelagica

Citation: Hastigerina parapelagica Saito & Thompson, in Saito et al. 1976
taxonomic rank: species
Type specimens: 211734
Type sample (& lithostrat): V26-128. 571 cm
Type age (chronostrat): Holotype (plate 2. figure 2). from Pleistocene; Paratype: Brady, 1884. pl. 83. fig. 8.
Type locality: lat. 20° 27' N. long. 83° 22'W. 3868 m
Type repository: Washington, USNM

Linked specimens: USNM-211374

Current identification/main database link: Hastigerina pelagica (d'Orbigny, 1839)


Original Description

Test large, coiled in a low trochospire becoming nearly planispiral with ontogeny, about 2-2 1/2 whorls of rapidly enlarging, partially embracing, ovoid chambers becoming quite radially elongate in the final convolution; equatorial periphery very lobulate; sutures on both spiral and umbilical sides radial, deep, not incised, becoming limbate at the base of the chambers towards the biumbilical depressions; aperture a symmetrical, wide and high arch, interiomarginal, equatorial, parallel to the axis of coiling, surrounded by a prominent, thick, almost imperforate lip extending completely around the aperture to both the spiral and umbilical depressions; wall calcareous, densely perforate throughout with large, deep, round pores; spines triradiate, only penetrating the test surface along the equatorial periphery.

Etymology:
Derivation of name : para - Greek. near; + species pelagica.

Extra details from original publication
Distribution: The species can be considered very rare. Its temporal and spatial distribution is unknown. but probably occupies similar limits as H. pelagica and H. digitiformans.

Remarks: Some workers have expressed the opinion that H. pelagica and the forms here called Hastigerina parapelagica. n. sp., and Hastigerinopsis digitiformans n. gen., n. sp. belong to a growth series of a single species. Bé (1965) found that "H. digitata" (=H. digitiformans) only occurs in bathypelagic depths. and concluded that forms known as H. pelagica, H. parapelagica, and H. digitiformans represented successive maturation stages of H. pelagica. The conclusion of Banner and Blow (1960. p. 26) is accepted here, however, that these three are separate and quite distinct species. H. parapelagica is larger in test size and more lobulate in the final convolution than H. pelagica, and larger in test size (for an equal number of chambers) and larger in chamber size although less clavate than H. digitiformans. Neither H. pelagica nor H. digitiformans have the partially limbate sutures of H. parapelagica, caused by the incomplete embracement of the partially perforate apertural lip of the previous chamber by the subsequent chamber. near the biumbilical depressions (plate 2, figures 2a. 2c). Spine bases of this species are quite large and triangular (plate 6. figure 6. lower right). partially extending onto nearby pores. Spines originating on chambers of earlier whorls which penetrate a later chamber (plate 6, figure 6, upper left) create a simple spine base on the new surface which holds the spine but does not attach to it. Complete spines were not preserved on the fossil material studied here or in the literature; it is. however, inferred from its generic affinity with Hastigerina pelagica and Hastigerinopsis digitiformans that the spines are triradiate throughout their length and possess spinal barbs.

References:

Saito, T., Thompson, P. R. & Breger, D. (1976). Skeletal ultra-microstructure of some elongate-chambered planktonic foraminifera and related species. In, Takayanagi, Y. & Saito, T. (eds) Progress in Micropaleontology, Special Publication. Micropaleontology Press, The American Museum of Natural History, New York 278-304. gs


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Hastigerina parapelagica compiled by the pforams@mikrotax project team viewed: 12-11-2024

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