rad_org Dipylissa bensoni img546.jpg
rad_org Dipylissa bensoni img547.jpg
rad_org Dipylissa bensoni img568.jpg
rad_org Dipylissa bensoni img546.jpg
rad_org Dipylissa bensoni img547.jpg
rad_org Dipylissa bensoni img568.jpg
1966 Spirema sp. - Benson p. 268-269; pl. 18, figs. 9-10
1983 Spirema sp. - Benson p. 508; pl. 6, figs. 3-4
1988 Dipylissa bensoni - Dumitrica p. 190, 192; pl. 3, figs. 1-7; pl. 4, figs. 11-15; pl. 6, figs. 1-15
1998 Dipylissa bensoni - Boltovskoy fig. 15.83
From Suzuki Paleotax db:
1989 Dipylissa bensoni Dumitrica Dumitrica pl. 12, figs. 18-24
1989 Dipylissa bensoni n. sp. Dumitrica p. 190, 192, pl. 3, figs. 1-7, pl. 4, figs. 11-15, pl. 6, figs. 1-15
2017 Dipylissa bensoni Dumitrica Chen et al. p. 157, pl. 47, figs. 7-14
Catalog entries: Dipylissa bensoni
type material: D. bensoniOriginal description: Shell small, oval, in mature stage formed of three systems of caps. Caps subbemispherical to globular and slightly flattened in successively equatorial and sagittal planes. In optic section these systems appear as oval concentric shells connected to one another by numerous thin radial bars. Wall generally thin, with numerous circular to subpolygonal pores of unequal size and arrangement. Gates narrow, semilunar, open successively in frontal and dorsal directions.
Maximum length of mature shell 90-110µm, breadth 75-90µm, distance between systems of caps 15-20µm.
Remarks on original description: [Equaivalent to Spirema sp., Benson, 1966, p.268, pl. 18, figs. 9-10; Spirema sp., Sachs, 1973 [unpublished Ph.D. thesis], p. 158, pl. 2, fig. 4b, c; Spirema sp., Benson, 1983, p. 508, pl. 6, figs. 3-4.
Rare but widespread in the late Pleistocene and Holocene of south and north Pacific (Benson, 1966, 1983; Sachs, 1973).
Benson 1966 - Dipylissa bensoni Test an involute spiral with three recognizable chambers, the last two chambers being bulbous or spherical as in a globigerinid foraminifer. First chamber a small, latticed, spherical shell with 2-3 equal, polygonal pores on its half circumference. Second spherical chamber arises from inner shell and completely envelops this shell and closes upon itself. Third chamber larger than second, spherical, completely covers the proximal portion of the whorl of the second chamber. No large opening in third chamber visible. Most tests oriented so that edge views of the test are observed; in this position the outline of the test is similar to a figure 8 but with one chamber smaller than the other. Numerous thin, cylindrical radial beams arise from the surface of the first chamber and join with the inner surfaces of the second and third chambers. Pores of the two outer chambers equal in size, polygonal to subpolygonal, hexagonally arranged, with rudimentary polygonal frames, approximately 10-12 pores on half the circumference of the third (largest) chamber. Surface of test with thorns or short, thin, conical spines arising from the nodes of the intervening bars. In one test an outer, thin-walled, small-pored, smooth ellipsoidal mantle, supported by the surface spines, partially envelops the test. Measurements: based on 4 specimens from station 27: length of test (edge view of spiral) 75-91 m; diameter of first chamber 12-15 µm of second chamber 47-54 µm, of third chamber 53-62 µm. Remarks: The resemblance of this species to some globigerinid foraminifers is remarkable; however, there is no doubt that this species is a radiolarian. Reference to this species in the literature could not be found; therefore, it is a new species. Because of its rare occurrence in the Gulf its complete range of variation could not be investigated. For this reason a new name is not proposed for this taxon. Distribution: This species occurs rarely in the Gulf at stations 27, 34, 46, 56, 60, 64, 93, and 99 in the southern half of the Gulf and at stations 106 and 151 in the northern half. It is, therefore, an oceanic species with little affinity for Gulf waters. \ From: Benson, 1966, p. 268-269; pl. 18, figs. 9-10:Spirema sp.
Published descriptions
Geological Range:
Last occurrence (top): Extant. Data source: Lazarus et al. 2015 - "R age group"
First occurrence (base): within Quaternary Period (0.00-2.59Ma, base in Gelasian stage). Data source: Lazarus et al. 2015 - "R age group"
Plot of occurrence data:
Benson, R. N. (1966). Recent Radiolaria from the Gulf of California. Thesis, Minnesota University. 1-577. gs Benson, R. N. (1983). Quaternary radiolarians from the Mouth of the Gulf of California, Deep Sea Drilling Project Leg 65. Initial Reports of the Deep Sea Drilling Project. 65: 491-523. gs Boltovskoy, D. (1998). Classification and distribution of south Atlantic recent polycystine Radiolaria. Palaeontologia Electronica. (2): -. gs Dumitrica, P. (1988). New families and subfamilies of Pyloniacea (Radiolaria). Revue de Micropaléontologie. 31(3): 178-195. gsReferences:
 |
Dipylissa bensoni compiled by the radiolaria@mikrotax project team viewed: 15-9-2024
Short stable page link: https://mikrotax.org/radiolaria/index.php?id=203965 Go to Archive.is to create a permanent copy of this page - citation notes |