USGS 18634 - Melajo Clay, Melago River area: Late/Upper Miocene, Trinidad and Tobago

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Bivalvia - Arcida - Arcidae
Anadara (Scapharca) placata
original and current combination Scapharca
Anadara (Anadara) inaequilateralis (Maury 1917)
Bivalvia - Pectinida - Pectinidae
Pecten (Pecten) archon
Aequipecten (Plagioctenium) demiurgus Dall 1898
recombined as Argopecten demiurgus
Bivalvia - Pectinida - Anomiidae
Anomia simplex d'Orbigny 1845
Bivalvia - Carditida - Crassatellidae
Eucrassatella trinitaria (Maury 1925)
recombined as Eucrassatella (Hybolophus) trinitaria
Bivalvia - Pholadida - Corbulidae
Caryocorbula (Caryocorbula) helanae
Notocorbula islatrinitatis (Maury 1925)
recombined as Varicorbula islatrinitatis
Bivalvia - Cardiida - Veneridae
Chione (Lirophora) caroniana
original and current combination Lirophora
Dosinia (Dosinia) grandis Nelson 1870
synonym of Dosinia (Dosinia) ponderosa
Macrocallista maculata (Linnaeus 1758)
Pleiorytis caroniana (Maury 1925)
Bivalvia - Cardiida - Solecurtidae
Tagelus (? Mesopleura) mansfieldi
Bivalvia - Cardiida - Tellinidae
Apolymetis trinitaria (Dall 1900)
recombined as Florimetis trinitaria
Macoma (Psammacoma) informal sp. A (Dall 1900)
original and current combination Psammacoma
Eurytellina melajoensis
Bivalvia - Cardiida - Cardiidae
Trigoniocardia (Trigoniocardia) maturensis
Trigoniocardia (Trigoniocardia) melajoensis Jung 1969
recombined as Trigoniocardia (Goniacardia) melajoensis
Bivalvia - Protobranchia - Nuculanidae
Adrana perprotracta (Dall 1912)
synonym of Adrana newcombi
Gastropoda - Neogastropoda - Olividae
Oliva (Oliva) couvana Maury 1925
Gastropoda - Neogastropoda
Ancilla (Eburna) caroniana (Maury 1925)
recombined as Eburna caroniana
Gastropoda - Neogastropoda - Columbellidae
Parametaria prototyphus
Strombina melajoensis Jung 1969
recombined as Sincola (Dorsina) melajoensis
Gastropoda - Neogastropoda - Buccinidae
Cantharus sp. Röding 1798
Hanetia semiglobosa
Gastropoda - Neogastropoda - Nassariidae
Calophos rohri (Rutsch 1942)
    = Gordanops baranoanus Anderson 1929
Landau and Marques da Silva 2010
Nassarius (Uzita) informal sp. A (Adams and Adams 1853)
Gastropoda - Neogastropoda - Fasciolariidae
Fusinus sp. Rafinesque 1815
Latirus (Polygona) cf. infundibulum (Gmelin 1791)
Gastropoda - Neogastropoda - Cancellariidae
Cancellaria (Euclia) montserratensis (Maury 1925)
recombined as Euclia montserratensis
Cancellaria cf. sanctifrancisci
Trigonostoma (Emmonsella) sp. Olsson and Petit 1964
synonym of Ventrilia
Cancellaria (Charcolleria) sp. Olsson 1942
synonym of Massyla
Gastropoda - Neogastropoda - Cystiscidae
Persicula (Rabicea) couviana (Maury 1925)
synonym of Persicula propeobesa
Gastropoda - Neogastropoda - Marginellidae
Prunum (Egouena) calypsonis (Maury 1925)
Prunum (Egouena) springvalensis (Maury 1925)
Volvarina informal sp. A (Hinds 1844)
Gastropoda - Neogastropoda - Muricidae
Murex (Chicoreus) cf. brevifrons (Lamarck 1822)
    = Chicoreus (Triplex) cornurectus Guppy 1876
Landau and Marques da Silva 2010
Murex (Phyllonotus) cf. pomum (Gmelin 1791)
recombined as Chicoreus (Phyllonotus) pomum
Murex (Murex) chrysostoma Sowerby 1834
recombined as Vokesimurex chrysostoma
Thais (Stramonita) informal sp. A (Schumacher 1817)
original and current combination Stramonita
Gastropoda - Neogastropoda - Conidae
Conus springvalensis Mansfield 1925
recombined as Conus imitator springvalensis
Conus couvaensis Vokes 1938
Gastropoda - Neogastropoda - Terebridae
Strioterebrum cf. gatunense
Gastropoda - Eulimidae
Balcis egregia
Gastropoda - Naticidae
Natica (Naticarius) canrena (Linnaeus 1758)
recombined as Naticarius canrena
Natica (Naticarius) aff. canrena (Linnaeus 1758)
recombined as Naticarius canrena
Polinices stanislasmeunieri Maury 1917
Gastropoda - Vermetidae
Petaloconchus sculpturatus Lea 1846
Subspecies: P. sculpturatus alcimus
Gastropoda - Calyptraeidae
Crepidula plana Say 1822
Gastropoda - Ranellidae
Cymatium sp. Röding 1798
Gastropoda - Bursidae
Bursa (Bursa) aff. thomae (d'Orbigny 1841)
synonym of Bursa rhodostoma
Gastropoda - Sorbeoconcha - Turritellidae
Turritella (Broderiptella) plaigyrata
Springvaleia leroyi
Gastropoda - Architectonicidae
Architectonica (Architectonica) nobilis (Röding 1798)
original and current combination Architectonica nobilis
Subspecies: A. (A.) nobilis nobilis
Gastropoda - Trochidae
Calliostoma caronianum Maury 1925
recombined as Calliostoma (Calliostoma) caronianum
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. Collection is derived from the basal limestone
Lithology and environment
Primary lithology:shelly/skeletal poorly lithified conglomeratic "limestone"
Includes fossils?Y
Lithology description: Limestone with large mollusks, that graded out of a conglomerate.
Environment:shallow subtidal indet.
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 basal assemblage, a carbonate and shallow water environment and is hence assigned to a carbontae - shallow subtidal 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:60637
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:A. Hendy Research group:marine invertebrate
Subset of collection #:60408
Created:2006-05-19 08:23:10 Last modified:2013-11-25 13:37:23
Access level:the public Released:2006-05-19 08:23:10
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:

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]