ammonites
banner

Swisshelm Mts. amphibian site: Westphalian A - Westphalian B, Arizona

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Agnatha - Conodontophorida
Adetognathus lautus
Adetognathus gigantus
Idiognathodus humerus
Idiognathodus delicatus
Agnatha - Conodonta
Spathognathodus coloradoensis
Chondrichthyes - Xenacanthiformes - Xenacanthidae
Xenacanthidae indet. Fritsch 1889
Chondrichthyes - Petalodontiformes - Petalodontidae
Petalodontidae indet. Newberry and Worthen 1866
Gnathostomata - Dipnoi - Lepidosirenidae
cf. Gnathorhiza serrata Cope 1883
genus name spelled "Gnathoriza" in the reference
unclassified
? Helodontidae indet.
Tetrapoda
Tetrapoda indet. Goodrich 1930
UALP 4956 (single limb fragment), 5267 ("collection of large tetrapod bone fragments")
Amphibia - Lepospondyli
? Lepospondyli indet. (von Zittel 1887)
23 elements
UALP 5186 (two fragmentary ulnae), 5187 (? pectoral girdle element), 5189 (? fibula), 5199 (single atlas), 5200 (fragment of left femur), 5232 (pterygoid), 5242 (a jaw reminiscent of Hylerpeton longidentatum), 5251, 5252 (both are incomplete tibiae), 5253 to 5255 (all are probably fibulae), 6023 (two ribs), 6226 (crushed left humerus), 6228 (rib), 6230 (several radii), 6231 (scapula with associated clavicle or cleithrum), 6235 (pterygoid); list comprises only the more complete specimens
Amphibia - Microsauria - Gymnarthridae
Elfridia bulbidens n. gen., n. sp. Thayer 1985
21 elements
UALP 4960, 4961, 4969, 4970 (type), 5171, 5172, 5176, 5226, 5230, 5231, 5865 to 5868, 6037, 6038, 6225, 6232 to 6234, 6238 (all are single bones or bone fragments)
Amphibia - Aistopoda - Ophiderpetontidae
Ophiderpeton swisshelmense n. sp. Thayer 1985
15 elements
UALP 4958, 4963, 5149, 5164, 5167 (type), 5168, 5175, 5202, 5208, 5692, 5864, 6036, 6057, 6058, 6222 (all are single vertebrae)
Amphibia - Aistopoda
Phlegethontia phanerhapha n. sp. Thayer 1985
2 specimens
nomen dubium belonging to Phlegethontiidae
UALP 5154 (type), 6035
Stegocephali - Nectridea - Urocordylidae
? Ptyonius olisthmonaias n. sp. Thayer 1985
14 elements
UALP 5161, 5162, 5170, 5207, 5211, 5212, 5264 (type), 5694, 5857 to 5860, 6212, 6223 (all are single bones)
Stegocephali - Nectridea
Arizonerpeton wellsi n. gen., n. sp. Thayer 1985
24 elements
UALP 4947 (type), 4948 to 4950, 4957, 5147, 5148, 5151, 5152, 5156 to 5158, 5163, 5165, 5181, 5203, 5266, 5691, 5693, 5701, 5861 to 5863, 6211 (all are single vertebrae)
see common names
Geography
Country:United States State/province:Arizona County:Cochise
Coordinates: 31.7° North, 109.6° West (view map)
Paleocoordinates:3.8° South, 44.2° West
Basis of coordinate:estimated from map
Altitude:1585 meters
Geographic resolution:small collection
Time
Period:Carboniferous
10 m.y. bin:Carboniferous 4
Key time interval:Westphalian A - Westphalian B
Age range of interval:318.1 - 311.3 m.y. ago
Stratigraphy
Formation:Black Prince Limestone
Stratigraphic resolution:bed
Stratigraphy comments: "The amphibian bed [is] located one meter below the top of the Black Prince [Limestone] [...] The Swisshelm Mountain amphibian bed is dated near the Morrowan-Derryan(= Atokan) boundary, equivalent to the boundary of Westphalian A and B of Europe" (Thayer, 1985).
Lithology and environment
Primary lithology:intraclastic,shelly/skeletal,gray,yellow silty "limestone"
Includes fossils?Y
Lithology description: "light yellow-gray, silty intrabiomicrudit"
Environment:shallow subtidal indet.
Geology comments: "The interpretation best fitting the evidence is a partially protected estuarine environment (for the algal oncolites and marine fauna), close to the outlet of a sluggish coastal river (for transporting the terrestrial and freshwater faunal elements)." (Thayer, 1985).
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils,microfossils
Preservation of anatomical detail:variable
Articulated whole bodies:none
Temporal resolution:time-averaged
Spatial resolution:allochthonous
Taphonomy comments: Some bones show traces of wear through transport, others are completely unworn but may have been transported as a whole carcass into the environment before burial and disarticulation by burrowing organisms. (Thayer, 1985).
Collection methods and comments
Collection excludes:some macrofossils,difficult macrofossils
Collection methods:bulk,acetic
Reason for describing collection:taxonomic analysis
Collection method comments: "Disarticulated faunal elements were obtained by digesting blocks of limestone and silty limestone in a 15 percent solution of acetic acid. The insoluble residue was washed through a 28-mesh screen to remove fine material." (thayer, 1985).
UALP = University of Arizona Laboratory of Paleontology
Metadata
Also known as:UALP 7205
Database number:92271
Authorizer:J. Mueller Enterer:T. Liebrecht
Modifier:T. Liebrecht Research group:micropaleontology,vertebrate
Created:2009-11-04 10:29:34 Last modified:2009-11-04 12:34:23
Access level:the public Released:2009-11-04 10:29:34
Reference information
Primary reference:
31089 D. W. Thayer. 1985. New Pennsylvanian Lepospondyl Amphibians from the Swisshelm Mountains, Arizona. Journal of Paleontology 59(3):684-700 [J. Mueller/T. Liebrecht]