Pachyphyllum nevadense

Taxonomy

Pachyphyllum

Kingdom: Animalia
Phylum: Cnidaria
Class: Anthozoa
Order: Stauriida
Family: Phillipsastreidae
Genus: Pachyphyllum
Species: Pachyphyllum nevadense
Author Citation Stumm 1948

Geological Time Scale

Eon: Phanerozoic
Era: Paleozoic
Period: Devonian
Sub Period: None
Epoch: Late
International Age: Frasnian

Stratigraphy

Martin Formation

Provenance

Collector: Me
Acquired by: Field Collection

Dimensions

Width: 52 mm
Thickness: 25 mm

Location

Superior
Pinal County
Arizona
United States

• arizona
• devonian
• frasnian
• martin formation
• pachyphyllum nevadense
• pinal county
• superior

Comments

This is a small form of Pachyllum nevadense that has corallites with small corallas (the circular structures that have a high rim that stick above the surface). The coralla rim diameters range from 1.25 mm to 2.5 mm and average 1.5 mm to 1.75 mm. The corallites average 2.5 mm to 8 mm apart center to center with an average of 4 mm to 5 mm apart. They have an average of 20 septa. The measurements partly overlap with those described for the species by Stumm in 1948: coralla rim diameter of 2 mm to 4 mm; average of 3 mm; distance from corallites centers of 5 mm to 10 mm; 18 to 24 septa. 
 

Since there is a lot of variability of the species in the same colony, at the same site, from site to site in Arizona and the US, I consider that this a variety of Pachyphyllum nevadense.

References: 

Stumm, Erwin C. “Upper Devonian Compound Tetracorals from the Martin Limestone.” Journal of Paleontology, vol. 22, no. 1, 1948, pp. 40–47. JSTOR, www.jstor.org/stable/1299252.

 

Luke, Keith J., 1978. CORALS OF THE DEVONIAN GUILMETTE FORMATION FROM THE LEPPY RANGE NEAR WENDOVER, UTAH, NEVADA. BRIGHAM YOUNG UNIV. GEOL. STUD.; USA; DA. 1978; VOL. 25; NO 3; PP. 83-98.

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