Swisshelm Mts. amphibian site (Carboniferous to of the United States)

Also known as UALP 7205

Where: Cochise County, Arizona (31.7° N, 109.6° W: paleocoordinates 4.0° S, 44.5° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Black Prince Limestone Formation, Westphalian A to Westphalian A (318.1 - 314.6 Ma)

• "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).

• bed-level stratigraphic resolution

Environment/lithology: shallow subtidal; intraclastic, shelly/skeletal, gray, yellow, silty limestone

• "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).
• "light yellow-gray, silty intrabiomicrudit"

Size classes: macrofossils, microfossils

Collection methods: bulk, acetic

• "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

Primary reference: D. W. Thayer. 1985. New Pennsylvanian Lepospondyl Amphibians from the Swisshelm Mountains, Arizona. Journal of Paleontology 59(3):684-700 [J. Mueller/T. Liebrecht]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 92271: authorized by Johannes Mueller, entered by Torsten Liebrecht on 04.11.2009

Creative Commons license: CC BY (attribution)

Taxonomic list

Conodonta
 Conodontophorida -
  -
 Ozarkodinida - Idiognathodontidae
Chondrichthyes
 Xenacanthiformes - Xenacanthidae
Xenacanthidae indet. Fritsch 1889 elasmobranch
 Petalodontiformes - Petalodontidae
Petalodontidae indet. Newberry and Worthen 1866 chimaera
 Helodontiformes - Helodontidae
Osteichthyes
 Dipnoi - Gnathorhizidae
cf. Gnathorhiza serrata Cope 1883 lungfish
genus name spelled "Gnathoriza" in the reference
  -
Tetrapoda indet.
UALP 4956 (single limb fragment), 5267 ("collection of large tetrapod bone fragments")
 Lepospondyli -
? Lepospondyli indet. tetrapod
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
 Aistopoda - Ophiderpetontidae
Ophiderpeton swisshelmense n. sp. Thayer 1985 tetrapod
UALP 4958, 4963, 5149, 5164, 5167 (type), 5168, 5175, 5202, 5208, 5692, 5864, 6036, 6057, 6058, 6222 (all are single vertebrae)
 Aistopoda - Phlegethontiidae
Phlegethontia phanerhapha n. sp. Thayer 1985 tetrapod
UALP 5154 (type), 6035 (Holotype; a posterior braincase fragment including a notochordal pit, the right expccipital, and part of the right otic capsule)
 Microsauria - Gymnarthridae
Elfridia bulbidens n. gen. n. sp.
Elfridia bulbidens n. gen. n. sp. Thayer 1985 tetrapod
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)
 Nectridea - Urocordylidae
? Ptyonius olisthmonaias n. sp. Thayer 1985 tetrapod
UALP 5161, 5162, 5170, 5207, 5211, 5212, 5264 (type), 5694, 5857 to 5860, 6212, 6223 (all are single bones)
 Nectridea -
Arizonerpeton wellsi n. gen. n. sp.
Arizonerpeton wellsi n. gen. n. sp. Thayer 1985 tetrapod
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)