USGS 18399 - Melajo Clay, Melago River area: Late/Upper Miocene, Trinidad and Tobago

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Gastropoda - Trochidae
Calliostoma olssoni (Maury 1925)
recombined as Calliostoma (Elmerlinia) olssoni
Gastropoda - Epitoniidae
Epitonium (Epitonium) aff. foliaceicostatum
Epitonium (Asperiscala) rohri
Gastropoda - Eulimidae
Niso grandis
Gastropoda - Neotaenioglossa - Calyptraeidae
Crepidula plana Say 1822
Calyptraea centralis (Conrad 1841)
Gastropoda - Cerithiidae
Cerithium harrisi
Gastropoda - Turritellidae
Turritella (Broderiptella) aff. mimetes (Brown and Pilsbry 1911)
Turritella (Broderiptella) planigyrata (Guppy 1867)
Turritella (Broderiptella) bifastigata (Nelson 1870)
Subspecies: T. (B.) bifastigata cartagenensis
Gastropoda - Pseudomelaniidae
Miraclathurella ralla
Carinodrillia meraca
Gastropoda - Neogastropoda - Olividae
Olivella (Minioliva) fundarugata
Gastropoda - Neogastropoda - Buccinidae
Strombinophos perdoctus
Gastropoda - Neogastropoda - Nassariidae
Nassarius (Uzita) trinitatensis Jung 1969
Calophos rohri (Rutsch 1942)
    = Gordanops baranoanus Anderson 1929
Landau and Marques da Silva 2010
Gastropoda - Neogastropoda - Columbellidae
Anachis (Costoanachis) obesa (Adams 1845)
recombined as Parvanachis obesa
Strombina (Sincola) crassilabrum (Guppy 1874)
Jung 1989 2 specimens
recombined as Sincola (Sincola) crassilabrum
Gastropoda - Neogastropoda - Mangeliidae
Ithycythara hilaris
Gastropoda - Neogastropoda - Turridae
Polystira informal sp. B Woodring 1928
Gastropoda - Neogastropoda - Muricidae
? Calotrophon hutchisoni
Eupleura lehneri Jung 1969
Gastropoda - Naticidae
Polinices stanislasmeunieri Maury 1917
Natica (Naticarius) aff. canrena (Linnaeus 1758)
recombined as Naticarius canrena
Gastropoda - Tornidae
Cochliolepis pluscula
Teinostoma (Aepystoma) caroniense
Teinostoma (Aepystoma) melajoensis
Teinostoma (Pseudorotella) nugax
Teinostoma (Pseudorotella) spretum
Gastropoda - Caecidae
Caecum informal sp. A Fleming 1813
Caecum informal sp. B Fleming 1813
Caecum informal sp. C Fleming 1813
Gastropoda - Vitrinellidae
Cyclostremiscus (Ponocyclus) pentagonus (Gabb 1873)
Gastropoda - Heterostropha - Acteonidae
Rictaxis sp. Dall 1871
Gastropoda - Opisthobranchia - Cylichnidae
Cylichnella altera
Acteocina canaliculata (Say 1826)
Bivalvia - Arcida - Noetiidae
Noetia (Eontia) centrota (Guppy 1867)
Noetia (Noetia) sheldoniana (Maury 1912)
Bivalvia - Arcida - Arcidae
Anadara (Scapharca) placata
original and current combination Scapharca
Anadara (Anadara) inaequilateralis (Maury 1917)
Bivalvia - Pectinida - Anomiidae
Anomia simplex d'Orbigny 1845
Bivalvia - Pectinida - Pectinidae
Aequipecten (Plagioctenium) cf. maturensis
synonym of Argopecten
Bivalvia - Lucinida - Lucinidae
Lucina (Lucinisca) roigi
Bivalvia - Pholadida - Corbulidae
Caryocorbula (Caryocorbula) helenae
Caryocorbula (Caryocorbula) sp. Gardner 1926
Notocorbula sp. Iredale 1930
spelled with current rank as Corbula (Notocorbula)
Bivalvia - Cardiida - Veneridae
Pitar (Lamelliconcha) circinatus
Pitar (Lamelliconcha) labreanus
Chione (Lirophora) caroniana
original and current combination Lirophora
Dosinia (Dosinia) grandis Nelson 1870
synonym of Dosinia ponderosa
Dosinia (Dosinia) sp. Scopoli 1777
Bivalvia - Cardiida - Cardiidae
Trigoniocardia (Trigoniocardia) maturensis
Trachycardium (Dallocardia) sanctidavidis
spelled with current rank as Dallocardia
Bivalvia - Cardiida - Tellinidae
Merisca trinidadensis
Temnoconcha aff. brasiliana
Tellidora sp. Morch 1856
Eurytellina melajoensis
spelled with current rank as Tellina (Eurytellina)
? Eurytellina oligoscissulata
spelled with current rank as Tellina (Eurytellina)
Moerella (Moerella) elinguis
spelled with current rank as Tellina (Moerella)
Bivalvia - Cardiida - Semelidae
Semele laevis (Sowerby 1833)
Subspecies: Semele laevis costaricensis
Semele aff. anteriocosta Vokes 1938
Bivalvia - Carditida - Crassatellidae
Crassinella guppyi (Dall 1896)
Bivalvia - Nuculanida - Nuculanidae
Calorhadia (Calorhadia) solivaga
Nuculana (Saccella) ludificans
original and current combination Saccella
Adrana perprotracta (Dall 1912)
synonym of Adrana newcombi
Scaphopoda - Dentaliida - Dentaliidae
Dentalium (Dentalium) divulgatum
see common names

Geography
Country:Trinidad and Tobago
Coordinates: 10.6° North, 61.1° West (view map)
Paleocoordinates:10.5° North, 59.6° West
Basis of coordinate:based on nearby landmark
Geographic resolution:outcrop
Time
Period:Neogene Epoch:Miocene
10 m.y. bin:Cenozoic 6
Key time interval:Late/Upper Miocene
Age range of interval:11.60800 - 5.33300 m.y. ago
Stratigraphy
Formation:Springvale Member:Melajo Clay
Regional section:Melajo River
Stratigraphic resolution:bed
Stratigraphy comments: The Melajo Clay Member of the Springvale Formation is correlated with the Savaneta Glaconitic Sandstone Member of the Springvale Formation, although part of it may be younger. The Melajo fauna is late Miocene in age. The Melajo Clay rests transgressively on the phyllites of the Northern Range with a basal conglomerate of about 1 m thickness. The conglomerate graes into a 1.5 m thick limestone, which is overlain by a bed of sand of about 1 m thickness. Above the sand is the Melajo Clay. The total thickness of the Melajo Clay is about 200 ft. It is unconformably overlain by Pleistocene sand and gravel deposits.
Lithology and environment
Primary lithology:yellow,blue unlithified silty claystone
Secondary lithology:coarse unlithified sandstone
Includes fossils?Y
Lithology description: Blue, yellowish weatheirng clay and silty clay with occasional sandy layers. Sand is probably coarse.
Environment:offshore
Geology comments: The Melajo fauna can be divided into two assemblages: one occurring the limestone and coarse sand near the base of the Melajo Clay, the other on in the overlying clay and silty clay. The difference of the two assemblages is facies controlled. The basal assemblage represents a typical, tropical, near-shore fauna, whereas the overlying assemblage points to a deeper environment. This collection is derived from the clay assemblage, a siliciclastic and deeper water environment and is hence assigned to a siliciclastic - offshore environment.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Preservation of anatomical detail:good
Collection methods and comments
Collection excludes:some macrofossils,some microfossils
Collection methods:selective quarrying,field collection
Reason for describing collection:taxonomic analysis
Museum repositories:PRI,USNM
Collection method comments: All material descibed in this report is reposited in the Naturhistorisches Mueum, Basel, or the USNM. Additional material collection from this unit is found at PRI.
Taxonomic list comments:Exhaustive for Mollusca, although author suggests that further collection would reveal additional forms. Corals, bryozoa and spines of echinoderms also exists in the unit, though are not listed. Van de Bold (1963) also lists ostracords from several localities. Foraminiferal assemblages are also listed in unpublished reports by Saunders.
Metadata
Database number:60399
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:A. Hendy Research group:marine invertebrate
Collections that are a subset of this one:60630, 60631, 60632, 60633, 60634, 60635
Created:2006-05-14 12:31:15 Last modified:2013-11-25 13:37:23
Access level:the public Released:2006-05-14 12:31:15
Creative Commons license:CC BY
Reference information

Primary reference:

17317. P. Jung. 1969. Miocene and Pliocene mollusks from Trinidad. Bulletins of American Paleontology 55(247):293-697 [A. Miller/A. Hendy]

Secondary references:

26828 P. Jung. 1989. Revision of the Strombina-group (Gastropoda; Columbellidae), fossil and living. Schweierische Paläontologische Abhandlungen 111:1-298 [A. Hendy/A. Hendy/A. Hendy]
36423 B. Landau and C. Marques da Silva. 2010. Early Pliocene gastropods of Cubagua, Venezuela: Taxonomy, palaeobiogeography and ecostratigraphy. Palaeontos 19:1-221 [A. Hendy/A. Hendy]