Calcivascularis cassidyi
Set number: 2877
-
1
-
2
-
3
-
4
-
5
-
6
-
7
-
8
-
9
-
10
-
11
10µm
Set number: 2875
-
1
-
2
-
3
-
4
-
5
-
6
-
7
-
8
10µm
Set number: 2876
-
1
-
2
-
3
-
4
-
5
-
6
-
7
-
8
-
9
-
10
10µm
Set number: 2879
-
1
-
2
-
3
-
4
-
5
-
6
10µm
Calcivascularis cassidyi Bergen et al., 2013
Small loxolith with a low wall and a relatively large, gently outward‑widening distal process composed of a protolith rim and curving central‑core segments that form a spiral pattern in side view in well‑preserved specimens.
In side view under cross‑polarised light, the loxolith base and the core of the distal process show parallel extinction (extinct at 0°) with length‑slow (+) elongation, whereas the protolith rim of the distal process displays symmetrical extinction (extinct at 45°).
This species is frequently observed in side view owing to its height‑to‑width ratio. The presence of a loxolith base renders its assignment to Calcivascularis questionable.
Bergen, J. A., Boesiger, T. M. & Pospichal, J. J. 2014. Low-latitude Oxfordian to Early Berriasian nannofossil biostratigraphy and its application to the subsurface of Eastern Texas. In: Hammes, U. & Gale, J. (Eds.) Geology of the Haynesville Gas Shale in East Texas and West Louisiana, U.S.A. American Association of Petroleum Geologists, Memoirs. 105: 69-102.
Holotype
Calcivascularis cassidyi
Bergen et al., 2013,
Late Kimmeridgian
DSDP Leg 76, Site 534, Blake-Bahama Basin, Atlantic Ocean