San Nicholas Island (SN-1) (Quaternary of the United States)

Also known as Vedder & Norris (1963) SN-1

Where: Ventura County, California (33.2° N, 119.5° W: paleocoordinates 33.2° N, 119.2° 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: taxonomic analysis

PaleoDB collection 37933: authorized by Austin Hendy, entered by Austin Hendy on 27.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Comprehensive for invertebrates
 Sessilia - Tetraclitidae
Tetraclita squamosa barnacle
Subspecies: Tetraclita squamosa rubescens
 Terebratulida - Cancellothyrididae
Terebratulina unguicula Carpenter 1864
 Arcida - Glycymerididae
"Glycymeris subobsoleta" = Glycymeris (Axinola) septentrionalis
"Glycymeris subobsoleta" = Glycymeris (Axinola) septentrionalis Middendorf 1849 clam
 Pectinida - Pectinoidae
"Chlamys cf. hastatus" = Chlamys (Chlamys) hastata
"Chlamys cf. hastatus" = Chlamys (Chlamys) hastata Sowerby 1842 scallop
 Ostreida - Ostreidae
Ostrea lurida Carpenter 1864 oyster
 Mytilida - Mytilidae
Septifer cf. bifurcatus Conrad 1837 mussel
 Carditida - Carditidae
"Glans subquadrata" = Glans carpenteri
"Glans subquadrata" = Glans carpenteri Lamy 1922 clam
 Pholadida - Pholadidae
Penitella penita Conrad 1837 clam
 Cardiida - Veneridae
"Protothaca staminea" = Leukoma staminea, "Irus lamellifer" = Irusella lamellifera, "Transennella tantilla" = Nutricola tantilla, "Petricola carditoides" = Petricola (Petricola) carditoides
"Protothaca staminea" = Leukoma staminea Conrad 1837 venus clam
"Irus lamellifer" = Irusella lamellifera Conrad 1837 venus clam
"Transennella tantilla" = Nutricola tantilla Gould 1853 venus clam
"Petricola carditoides" = Petricola (Petricola) carditoides Conrad 1837 venus clam
 Cardiida - Semelidae
Cumingia californica Conrad 1837 clam
 Cardiida - Neoleptonidae
Bernardina bakeri Dall 1910 clam
 Cardiida - Lasaeidae
"Lasaea cf. cistula" = Lasaea adansoni
"Lasaea cf. cistula" = Lasaea adansoni Gmelin 1791 clam
 Hiatellida - Hiatellidae
"Hiatella cf. arctica" = Hiatella (Hiatella) arctica
"Hiatella cf. arctica" = Hiatella (Hiatella) arctica Linnaeus 1767 clam
 Lucinida - Lucinidae
Epilucina californica Conrad 1837 clam
 Ptenoglossa - Epitoniidae
Epitonium cf. indianorum Carpenter 1864 wentletrap
Opalia cf. evicta wentletrap
Opalia wroblewskyi Mörch 1876 wentletrap
 Patellogastropoda - Lottiidae
Acmaea digitalis Eschscholtz 1833 limpet
Acmaea mitra Eschscholtz 1833 limpet
Acmaea ? pelta Eschscholtz 1833 limpet
 Opisthobranchia - Cylichnidae
Acteocina culcitella Gould 1853 barrel-bubble
 Triphoroidea - Triphoridae
 Triphoroidea - Cerithiopsidae
Cerithiopsis sp. Hanley 1849 snail
 Neogastropoda - Olividae
"Olivella cf. pedroana" = Olivella (Callianax) pedroana, "Olivella biplicata" = Olivella (Callianax) biplicata
"Olivella cf. pedroana" = Olivella (Callianax) pedroana Conrad 1855 olive snail
"Olivella biplicata" = Olivella (Callianax) biplicata Sowerby 1825 olive snail
 Neogastropoda - Columbellidae
Mitrella tuberosa Carpenter 1864 snail
Amphissa versicolor Dall 1871 snail
 Neogastropoda - Nassariidae
Nassarius mendicus snail
Subspecies: Nassarius mendicus cooperi
 Neogastropoda - Fasciolariidae
 Neogastropoda - Cystiscidae
 Neogastropoda - Mitridae
"Mitra idae" = Mitra (Atrimitra) idae
"Mitra idae" = Mitra (Atrimitra) idae Melville 1893 mitre shell
 Neogastropoda - Muricidae
Acanthina spirata unicorn
Subspecies: Acanthina spirata punctulata
Ocenebra lurida murex snail
Subspecies: Ocenebra lurida munda
Ocenebra interfossa murex snail
Ocenebra cf. beta murex snail
 Neogastropoda - Mangeliidae
"Mangelia ? interfossa" = Cythara (Mangelia), "Mangelia aff. rhyssa" = Cythara (Mangelia), Mangelia cf. variegata
"Mangelia ? interfossa" = Cythara (Mangelia) snail
"Mangelia aff. rhyssa" = Cythara (Mangelia) snail
Mangelia cf. variegata Carpenter 1864 snail
 Neogastropoda - Mitromorphidae
 Neogastropoda - Conidae
"Conus californicus" = Californiconus californicus
"Conus californicus" = Californiconus californicus Reeve 1844 cone shell
 Neogastropoda - Pseudomelatomidae
 Littorinoidea - Littorinidae
Littorina planaxis Philippi 1847 periwinkle
Littorina scutulata Gould 1849 periwinkle
 Vanikoroidea - Hipponicidae
Hipponix tumens hoof shell
Hipponix antiquatus Linnaeus 1767 hoof shell
 Vanikoroidea - Eulimidae
 Naticoidea - Naticidae
Lunatia cf. lewisii Gould 1847 moon snail
 Vermetoidea - Vermetidae
 Calyptraeoidea - Calyptraeidae
Crepidula perforans slipper shell
Crepidula adunca Sowerby 1824 slipper shell
"Crepidula aculeata" = Bostrycapulus aculeatus Gmelin 1791 slipper shell
 Rissooidea - Barleeidae
 Rissooidea - Rissoidae
 Rissooidea - Vitrinellidae
"Vitrinella stearnsii" = Vitrinella (Docomphala) stearnsi Bartsch 1907 snail
 Truncatelloidea - Assimineidae
 Truncatelloidea - Caecidae
 Sorbeoconcha - Cerithiidae
Bittium eschrichtii cerith snail
Subspecies: Bittium eschrichtii montereyense
Bittium armillatum cerith snail
Bittium attenuatum cerith snail
 Sorbeoconcha - Dialidae
"Diala" cf. marmorea Carpenter 1864 snail
 Pulmonata - Trimusculidae
 Basommatophora - Siphonariidae
 Pyramidelloidea - Pyramidellidae
 Haliotoidea - Haliotidae
 Turbinoidea - Turbinidae
Arene acuticostata snail
Subspecies: Arene acuticostata radiata
Astraea gibberosa Dillwyn 1817 red turban
 Turbinoidea - Phasianellidae
 Fissurelloidea - Fissurellidae
Fissurella volcano Reeve 1849 snail
Diodora aspera Rathke 1833 snail
 Trochoidea - Trochidae
Pupillaria cf. optabilis Carpenter 1864 top snail
Calliostoma ligatum Gould 1849 top snail
 Trochoidea - Tegulidae
 Dentaliida - Dentaliidae
"Dentalium semipolitum" = Dentalium semistriatum semipolitum
"Dentalium semipolitum" = Dentalium semistriatum semipolitum Broderip and Sowerby 1829 tusk shell
 Neoloricata - Mopaliidae
Placiphorella cf. velata Carpenter 1879 chiton
"Dendrochiton cf. thamnopora" = Mopalia (Dendrochiton) chiton
Mopalia muscosa Gould 1846 chiton
 Neoloricata - Callistoplacidae
Callistochiton crassicostatus Pilsbry 1893 chiton
 Neoloricata - Ischnochitonidae
Stenoplax sp. Carpenter 1879 chiton
"Stenoplax cf. conspicuus" = Stenoplax conspicua Pilsbry 1892 conspicuous chiton
Lepidozona sp. Pilsbry 1892 chiton
Tonicella lineata Wood 1815 lined red chiton
 Neoloricata - Acanthochitonidae
"Cryptochiton" stelleri Middendorf 1847 chiton
 Camarodonta - Strongylocentrotidae
Strongylocentrotus ? purpuratus Arnold 1903 sea urchin
 Scleractinia - Dendrophylliidae
Balanophyllia elegans Verrill 1864 stony coral