San Nicholas Island (SN-7) (Quaternary of the United States)

Also known as Vedder & Norris (1963) SN-7

Where: Ventura County, California (33.2° N, 119.5° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Unnamed Formation, Quaternary (2.6 - 0.0 Ma)

• Dune sand and fossiliferous marine terrace deposits of Quaternary age. These overlie Eocene strata. Fossils come from seven well-developed wave-cut platforms at altitudes of 25 to 990 feet. Several submerged terraces are present on the shelf adjacent to the island., the lowest being 400 ft below sea-level. Presumably all the terrace platforms on San Nicholas Island were cut later than the middle Pleistocene diastrophism recognized elsewhere in southern California. Terrace platforms are covered with a variety of sediments of marine and non-marine origin and range in thickness from a few inches to many feet.

• bed-level stratigraphic resolution

Environment/lithology: coastal; pebbly, shelly/skeletal, conglomeratic, calcareous sandstone

• Higher emergent terraces may represent wave-abraded platforms that were eroded during eustatic changes in sea level combined with tectonic uplift. The lowest emergent terrace may have been cut during eustatic sea-level changes followed by very slight regional seaward warping. Presumably all the terrace platforms on San Nicholas Island were cut later than the middle Pleistocene diastrophism recognized elsewhere in southern California
• Generally comprise poorly sorted calcareous sand and gravel composed primarily of mollusc shell fragments, echinoid plates and spines, calcareous algae, and bryozoans.

Size class: macrofossils

Collection methods: quarrying,

• Collections made by Vedder et al (1955-1956). Earlier collections by Cooper (1894), and Howard (1955)

Primary reference: J. G. Vedder and R. M. Norris. 1963. Geology of San Nicolas Island, California. United States Geological Survey Professional Paper 369:1-65 [A. Miller/A. Hendy/P. Wagner]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 37943: authorized by Austin Hendy, entered by Austin Hendy on 27.03.2004

Creative Commons license: CC0 (CC0)

Taxonomic list

• Comprehensive for invertebrates
Anthozoa
 Scleractinia - Dendrophylliidae
Balanophyllia elegans Verrill 1864 stony coral
Bivalvia
 Pectinida - Pectinoidae
"Hinnites giganteus" = Crassadoma gigantea
"Hinnites giganteus" = Crassadoma gigantea Gray 1825 scallop
 Mytilida - Mytilidae
Mytilus ? californianus Conrad 1837 mussel
 Cardiida - Semelidae
Cumingia californica Conrad 1837 clam
 Cardiida - Veneridae
"Transennella tantilla" = Nutricola tantilla, "Petricola carditoides" = Petricola (Petricola) carditoides
"Transennella tantilla" = Nutricola tantilla Gould 1853 venus clam
"Petricola carditoides" = Petricola (Petricola) carditoides Conrad 1837 venus clam
 Cardiida - Lasaeidae
"Lasaea cf. cistula" = Lasaea adansoni
"Lasaea cf. cistula" = Lasaea adansoni Gmelin 1791 kelly clam
 Cardiida - Neoleptonidae
Bernardina bakeri Dall 1910 clam
 Lucinida - Lucinidae
Epilucina californica Conrad 1837 clam
 Carditida - Carditidae
"Glans subquadrata" = Glans carpenteri
"Glans subquadrata" = Glans carpenteri Lamy 1922 clam
Gastropoda
  - Neptuneidae
Macron lividus Adams 1855 snail
 Neotaenioglossa - Calyptraeidae
Crepidula onyx Sowerby 1824 slipper shell
Crepidula adunca Sowerby 1824 slipper shell
Crucibulum spinosum Conrad 1855 slipper shell
Bostrycapulus decorus Collin 2019 slipper shell
 Epitonioidea - Epitoniidae
"Opalia cf. evicta" = Scalaria evicta, "Epitonium cf. indianorum" = Nitidiscala indianorum
"Opalia cf. evicta" = Scalaria evicta de Boury 1918 wentletrap
"Epitonium cf. indianorum" = Nitidiscala indianorum Carpenter 1864 wentletrap
 Neogastropoda - Buccinidae
"Searlesia" cf. dira Reeve 1846 true whelk
 Neogastropoda - Siphonaliidae
Calicantharus cf. fortis Carpenter 1866 snail
 Neogastropoda - Columbellidae
"Mitrella carinata" = Alia carinata Hinds 1844 dovesnail
Amphissa versicolor Dall 1871 snail
Mitrella tuberosa Carpenter 1864 snail
 Sorbeoconcha - Littorinidae
"Littorina scutulata" = Littorina (Littorina) scutulata
"Littorina scutulata" = Littorina (Littorina) scutulata Gould 1849 periwinkle
 Sorbeoconcha - Vermetidae
Petaloconchus complicatus Dall 1908 worm shell
"Spiroglyphus lituellus" = Dendropoma lituella Morch 1861 worm shell
 Sorbeoconcha - Caecidae
"Caecum dalli" = Caecum quadratum Carpenter 1857 snail
Caecum cf. californicum Dall 1885 snail
Fartulum cf. orcutti Dall in Orcutt 1885 snail
"Fartulum occidentale" = Fartulum dextroversum Carpenter 1857 snail
 Sorbeoconcha - Vitrinellidae
Vitrinella cf. oldroydi Bartsch 1907 snail
 Sorbeoconcha - Hipponicidae
Antisabia panamensis Adams 1852 hoof shell
 Sorbeoconcha - Rissoidae
"Alvania purpurea" = Alvinia purpurea
"Alvania purpurea" = Alvinia purpurea Dall 1871 snail
 Sorbeoconcha - Barleeiidae
Amphithalamus tenuis Bartsch 1911 snail
Barleeia cf. oldroydi Bartsch 1920 snail
Barleeia cf. subtenuis Carpenter 1864 snail
 Sorbeoconcha - Procerithiidae
"Bittium cf. attenuatum" = Lirobittium attenuatum, "Bittium armillatum" = Lirobittium armillatum
"Bittium cf. attenuatum" = Lirobittium attenuatum Carpenter 1864 snail
"Bittium armillatum" = Lirobittium armillatum Carpenter 1864 snail
 Patellida - Lottiidae
Lottia gigantea, "Acmaea cf. scabra" = Lottia scabra, "Acmaea cf. limatula" = Lottia limatula, "Acmaea scutum" = Lottia scutum, "Acmaea pelta" = Lottia pelta, "Acmaea digitalis" = Lottia digitalis, Acmaea mitra
Lottia gigantea Sowerby 1834 limpet
"Acmaea cf. scabra" = Lottia scabra Gould 1846 limpet
"Acmaea cf. limatula" = Lottia limatula Carpenter 1864 limpet
"Acmaea scutum" = Lottia scutum Eschscholtz 1833 limpet
"Acmaea pelta" = Lottia pelta Eschscholtz 1833 limpet
"Acmaea digitalis" = Lottia digitalis Eschscholtz 1833 limpet
Acmaea mitra Eschscholtz 1833 limpet
 Heterostropha - Trimusculidae
Trimusculus reticulatus Sowerby 1835 button snail
 Trochoidea - Phasianellidae
"Tricolia cf. pulloides" = Eulithidium pulloides
"Tricolia cf. pulloides" = Eulithidium pulloides Carpenter 1865 snail
 Trochoidea - Turbinidae
"Homalopoma cf. carpenteri" = Homalopoma (Homalopoma) luridum
"Homalopoma cf. carpenteri" = Homalopoma (Homalopoma) luridum Dall 1885 snail
 Trochoidea - Trochidae
"Tegula funebralis" = Chlorostoma funebrale
"Tegula funebralis" = Chlorostoma funebrale Adams 1855 top snail
 Lepetellida - Fissurellidae
 Lepetellida - Haliotidae
Haliotis cf. cracherodii Leach 1814 abalone
Polyplacophora
 Chitonida - Acanthochitonidae
"Cryptochiton" stelleri Middendorf 1847 chiton
Thecostraca
 Balanomorpha - Tetraclitidae
Tetraclita ? squamosa Bruguière 1789 green volcano barnacle
Subspecies: Tetraclita squamosa rubescens
Echinoidea
 Camarodonta - Strongylocentrotidae
Strongylocentrotus cf. franciscanus Agassiz 1863 sea urchin