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Bistarkum rigidium

Protozoa - Spumellaria - Angulobracchiidae


Description: Rays about equal in length, medium of width, one ray usually slightly wider than the other, both rays terminating in large ellipsoidal tips. Width of tips about equal to length of ray shafts. Test comprised of small irregularly arranged polygonal pore frames without prominent small nodes at vertices. Several spines with circular cross-section and variable length occurring at distal surface of tips and sides of rays.

Remarks: Bistarkum rigidium Yeh, differs from B. bifurcum Yeh, by lacking bifurcate tips and by having a wider test.

Etymology: Rigidius-a-um (Latin, adj.) rigid.

Bistarkum rigidium was named by Yeh (1987). Its type specimen is NMNS (000045) and is a 3D body fossil. Its type locality is Suplee-Izee area, OR-589D, which is in a Toarcian marine mudstone/limestone in the Snowshoe Formation of Oregon.

Sister species lacking formal opinion data

Synonymy list
YearName and author
1987Bistarkum rigidium Yeh p. 43 figs. Pl. 1, fig. 5; Pl. 21, fig. 5; Pl. 22, figs. 1, 3, 7, 11

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classProtozoaGoldfuss 1820
subphylumSarcodinaSchmarda 1871
classReticulareaLankester 1885
subclassRadiolaria(Müller 1858)
orderSpumellariaEhrenberg 1875
familyAngulobracchiidaeBaumgartner 1980

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

Bistarkum rigidium Yeh 1987
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No diagnoses are available
No measurements are available
Composition: silicap
Environment: marinep
Locomotion: passively mobilep
Life habit: planktonicp
Diet: omnivorep
Created: 2005-01-28 01:13:47
Modified: 2005-01-28 03:13:47
Source: p = phylum
Reference: Kiessling 1999

Age range: base of the Late/Upper Pliensbachian to the top of the Early/Lower Toarcian or 189.60000 to 182.00000 Ma

Collections (4 total)

Time interval Ma Country or state Original ID and collection number
Late/Upper Pliensbachian189.6 - 183.0USA (Oregon) Bistarkum rigidium (124323)
Early/Lower Toarcian183.0 - 182.0Japan Bistarkum rigidium (124830)
Early/Lower Toarcian183.0 - 182.0USA (Oregon) Bistarkum rigidium (124331 type locality: 124334)