Locality 4, Quebrada de Portachuelo (Permian of Venezuela)

Where: Merida, Venezuela (8.0° N, 71.3° W: paleocoordinates 5.5° S, 34.4° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Palmarito Formation, Kungurian (279.3 - 272.3 Ma)

• Area sampled is exposed in the side wall of the stream bed, and comprises about 2 m laterally and 1 m normal to bedding. Fusulinids and ammonoids suggest that locality 4 (and underlying localities 1 and 2) are "late Leonardian" (Kungurian) in age. Palmarito Fm contains Perrinites hilli and Parafusulina of Kungurian age.

• bed-level stratigraphic resolution

Environment/lithology: open shallow subtidal; silty packstone and calcareous siltstone

• Graded bedding and fine sorting suggests periods of moderate to high energy, but the lack of abrasion and alternation of fine sediments suggests they were probably short-lived. Deposited in shallow, warm water, above a soft substrate.
• Thin- to medium-bedded silty limestones, intercalated with thin-bedded calcareous siltstones. Compositionally a biomicrite, depositional texture classified as a packstone. Also contains silt- and sand-sized spherulites of possibly volcanic origin and fine needle-like calcitic forms interpreted as sponge spicules. Rip-up clasts present.

Size class: macrofossils

Preservation: replaced with silica

Collection methods: bulk, chemical,

• Sampled 2 m laterally and 1 m normal to bedding. Most were partially silicified (some totally silicified), etched with HCl. Dried silt periodically removed from block by air abrasion to speed decalcification.

Primary reference: P.R. Hoover. 1981. Paleontology, Taphonomy, and Paleoecology of the Palmarito Formation (Permian of Venezuela). Bulletins of American Paleontology 80(313):1-138 [D. Bottjer/M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 41508: authorized by David Bottjer, entered by Matthew Clapham on 15.07.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Crinoidea
  -
Crinoidea indet. Miller 1821 Sea lily
Columnals
Strophomenata
 Productida - Productidae
? Spinifrons grandicosta Hoover 1981
cf. grandicosta n. sp.
 Productida - Productellidae
Echinauris cf. liumbona Cooper and Grant 1975
"Kutorginella cf. umbonata" = Retaria umbonata Muir-Wood and Cooper 1960
Rugatia intermedia Hoover 1981
 Productida - Linoproductidae
Holotricharina hirsuta Cooper and Grant 1975
 Orthotetida - Derbyiidae
Derbyia sp. Waagen 1884
Derbyia cf. complicata Cooper and Grant 1974
Derbyia auriplexa Hoover 1981
 Orthotetida - Meekellidae
Meekella skenoides Girty 1908
 Strophomenida - Rugosochonetidae
"Stauromata esoterica n. gen." = Dyoros esoterica, Chonetinetes cf. varians
"Stauromata esoterica n. gen." = Dyoros esoterica Hoover 1981
Chonetinetes cf. varians Cooper and Grant 1975
Reflects minimum estimate based on valve ratios
Rhynchonellata
 Spiriferida - Trigonotretidae
 Athyridida - Athyrididae
Composita cf. pilula Cooper and Grant 1976
Bryozoa
  -
Bryozoa indet. Ehrenberg 1831
Ramose forms
Stenolaemata
 Cryptostomata -
"Fenestrida indet." = Fenestelloidea
"Fenestrida indet." = Fenestelloidea Astrova and Morozova 1956
Fenestellid forms
Cephalopoda
 Goniatitida - Perrinitidae
Perrinites hilli Smith 1903 ammonite
Gastropoda
 Murchisoniina - Phymatopleuridae
"Worthenia" cf. corrugata Chronic 1952 snail
 Caenogastropoda - Goniasmatidae
Goniasma sp. Tomlin 1930 snail
 Caenogastropoda - Orthonematidae
aff. Taosia sp. Girty 1939 snail
New genus aff. Taosia
 Cerithimorpha - Orthonemidae
Palaeostylus sp. Mansuy 1914 snail