PBDB Collection

Alisitos Fm. (UCB A-8317) (Cretaceous of Mexico)

Where: Baja California, Mexico (31.5° N, 116.7° W: paleocoordinates 29.9° N, 68.2° W)

• small collection-level geographic resolution

When: upper Member (Alisitos Formation), Late/Upper Aptian (122.5 - 113.0 Ma)

• Age: "Aptian to middle Albian." Squires and Saul (2004) confirming and following Allison (1974) place this collection in the Late Aptian.

• bed-level stratigraphic resolution

Environment/lithology: shallow subtidal; conglomerate

• "Poorly sorted dark volcanic breccia overlying A-8318."

Collection methods: mechanical,

Primary reference: E. C. Allison. 1955. Middle Cretaceous gastropoda from Punta China, Baja California, Mexico. Journal of Paleontology 29(3):400-432 [J. Alroy/M. Sommers/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 1878: authorized by John Alroy, entered by Mike Sommers on 10.06.1999, edited by Jonathan Marcot, Austin Hendy and Wolfgang Kiessling

Creative Commons license: CC BY (attribution)

Taxonomic list

• Abundances: A = 20+, C = 6-20, F = 3-5, R = 1-2. "A spectacular feature of the middle Albian deposits at Punta China is the fine preservation exhibited by many of the fossils. Despite the coarseness of some of the volcanic breccias, fragile tests of Forams, echinoids, and small molluscs are almost perfectly preserved. Pelecypods almost always occur with both valves intact. Some gastropods retain original pigmentation."

Show authors, comments, and common names

Foraminifera
Orbitolinacea - Orbitolinidae	Orbitolina texana Orbitolina texana
Nodosariata
Vaginulinida - Vaginulinidae	Lenticulina cf. subalta Lenticulina cf. subalta quest. ident. - originally entered as "Lenticulina cf. subalta"
Anthozoa
Scleractinia - Montlivaltiidae	Isastrea whitneyi Isastrea whitneyi Wells 1932 stony coral
Scleractinia - Eugyridae	"Myriophyllia cf. cuyleri" = Eugyra cuyleri "Myriophyllia cf. cuyleri" = Eugyra cuyleri Wells 1932 stony coral originally entered as "Myriophyllia cf. cuyleri"
Scleractinia - Astrocoeniidae	Astrocoenia sp. Astrocoenia sp. Milne-Edwards and Haime 1848 stony coral
Scleractinia - Montastraeidae	""Montastrea" sp." = Montastraea¹ ""Montastrea" sp." = Montastraea¹ Blainville 1830 stony coral
Demospongiae
Clavulina - Clionaidae	Cliona sp. Cliona sp. demosponge
Echinoidea
Echinoneoida - Conulidae	Pygopyrina sp. Pygopyrina sp. Pomel 1883 sea urchin
Gastropoda
-	"? Pyrazus harrissi n. sp." = Alamirifica harrissi "? Pyrazus harrissi n. sp." = Alamirifica harrissi Allison 1955 snail originally entered as "? Pyzarus harrissi"
Trochoidea - Colloniidae	Cirsochilus gilberti n. sp. Cirsochilus gilberti n. sp. Allison 1955 snail
Trochoidea - Trochidae	Tectus (Tectus) tomasensis n. sp. Tectus (Tectus) tomasensis n. sp. Allison 1955 top snail
Seguenzioidea - Chilodontaidae	Agnathodonta brooksi n. sp. Agnathodonta brooksi n. sp. Allison 1955 snail n. sp. - originally entered as "Agnathodonta brooksi"
Cerithioidea - Turritellidae	Omalaxis ? planorbis Omalaxis ? planorbis Blainville 1827 turret shell originally entered as "Omalaxis ? planorbis"
Cerithioidea - Potamididae	Pyrazus (Echinobathra) austinense, Pyrazus (Echinobathra) durhami n. sp. Pyrazus (Echinobathra) austinense Roemer 1888 horn snail Pyrazus (Echinobathra) durhami n. sp. Allison 1955 horn snail
Sorbeoconcha - Aporrhaidae	Anchura (Perissoptera) hannai Anchura (Perissoptera) hannai Allison 1955 snail quest. ident.
Sorbeoconcha - Naticidae	Natica importuna Natica importuna Nagao 1934 moon snail
Sorbeoconcha - Tylostomatidae	Tylostoma allisoni³ Tylostoma allisoni³ Squires and Saul 2004 snail
Sorbeoconcha - Procerithiidae	Cimolithium miyakoense, Cimolithium eleanorae, Uchauxia kirki, Uchauxia beali Cimolithium miyakoense Nagao 1934 snail var. tomasensis n. var. Cimolithium eleanorae Allison 1955 snail Uchauxia kirki Allison 1955 snail Uchauxia beali Allison 1955 snail
Heterostropha - Nerineidae	Nerinea (Plesioptygmatis) bosei, Nerinea (Plesioptygmatis) cf. pseudoconvexa, Nerinea (Plesioptygmatis) tomasensis Nerinea (Plesioptygmatis) bosei Allison 1955 snail Nerinea (Plesioptygmatis) cf. pseudoconvexa Stanton 1947 snail (Plesioptygmatis) - originally entered as "Nerinea cf. pseudoconvexa" Nerinea (Plesioptygmatis) tomasensis Allison 1955 snail
Heterostropha - Nerinellidae	Aptyxiella (Aptyxiella) cf. subula Aptyxiella (Aptyxiella) cf. subula Roemer 1888 snail (Aptyxiella) - originally entered as "Aptyxiella cf. subula"
Heterostropha - Acteonellidae	Actaeonella parvus Actaeonella parvus Stanton 1947 snail originally entered as "Acteonella parvus"
Heterostropha - Acteonidae	Liocarenus (Liocarenus) formosum Liocarenus (Liocarenus) formosum Cragin 1893 snail
Neritoidea - Neridomidae	Neritoma (Neridomus) delpeyae n. sp. Neritoma (Neridomus) delpeyae n. sp. Allison 1955 snail
Neritoidea - Neritidae	Corsania (Corsania) allisoni n. sp.², Semineritina apparata, Otostoma (Lyosoma) japonica Corsania (Corsania) allisoni n. sp.² Saul and Squires 1997 snail Semineritina apparata Cragin 1893 snail Otostoma (Lyosoma) japonica Nagao 1934 snail
Bivalvia
Carditida - Crassatellidae	Ptychomya ? densicostata Ptychomya ? densicostata Nagao 1934 clam originally entered as "Ptychomya ? densicostata"
Pholadida - Corbulidae	Corbula sp. Corbula sp. Bruguière 1789 clam
Hippuritida - Caprinuloideidae	Caprinuloidea sp. Caprinuloidea sp. Palmer 1928 rudist
Cardiida - Tellinidae	"Linearia sp." = Linearis "Linearia sp." = Linearis Conrad 1860 tellin clam
Ostreida - Gryphaeidae	Gryphaea wardi, Exogyra cf. quitmanensis Gryphaea wardi Hill and Vaughan 1898 oyster Exogyra cf. quitmanensis Cragin 1893 oyster originally entered as "Exogyra cf. quitmanensis"
Pectinida - Limidae	Lima (Mantellum) sp. Lima (Mantellum) sp. Röding 1798 file clam (Mantellum)
Pectinida - Neitheoidae	Neithea aff. occidentalis Neithea aff. occidentalis Conrad 1855 scallop originally entered as "Neithea aff. occidentalis"
Malacostraca
Decapoda -	Decapoda indet. Decapoda indet. Latreille 1802 decapod crab fragments

¹Kiessling 2008; ²Saul and Squires 1997; ³Squires and Saul 2004