Chengapara Fm - Zone IB (Miocene of India)

Where: India (25.2° N, 90.7° E: paleocoordinates 15.9° N, 88.6° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Chengapara Formation, Early/Lower Miocene (23.0 - 16.0 Ma)

• STRATIGRAPHIC RELATIONS: From Zone IB of Chengapara Formation, which regionally conformably overlies the Baghmara Fm (presumanly Early Miocene) and is unconformably overlain by the Dupitila Fm. THICKNESS: Zone is 16 m in thickness, within a ~30 m thick section. AGE: Burdigalian. STRATIGRAPHIC POSITION: From middle part of section, basal part of the Chengapara Fm.

• bed-level stratigraphic resolution

Environment/lithology: coastal; poorly lithified, calcareous sandstone

• ENVIRONMENT: Shallow siliciclastic marine environment.
• SPECIFIC LITHOLOGY: Calcareous sandstone and friable sandstone. LITHIFICATION: From both lithified and poorly-lithified facies, as stated in text.

Size class: macrofossils

Collection methods: surface (in situ),

• COLLECTORS: Presumably the authors, B. C. Lyngdoh, R. P. Tiwari, and R. P. Kachhara. REPOSITORY: Paleontology Museum of the Department of Geology, Pachunga University College, North-Eastern Hill University, Mizoram, India.

Primary reference: B. C. Lyngdoh, R. P. Tiwari, and R. P. Kachhara. 1999. Miocene Molluscan biosratigraphy of the Garo Hills, Meghalaya, India. Journal of the Paleontological Society of India 44:55-67 [A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 72084: authorized by Austin Hendy, entered by Austin Hendy on 24.05.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGES: Probably exhaustive for gastropoda and bivalvia. Some fishes also listed. NOMENCLATURE: Appears relatively modern nomenclature, with consistent use of subgeneric and species-level assignments.
 Arcida - Arcidae
Trisidos tortuosa Linnaeus 1758 clam
Bentharca "n. sp." Verrill and Bush 1898 clam
Scapharca "n. sp. 1" Gray 1847 clam
Scapharca "n. sp. 2" Gray 1847 clam
Anadara sp. Gray 1847 ark
Anadara "n. sp." Gray 1847 ark
Anadara garoensis Mukerjee 1939 ark
Anadara dichotoma Deshayes 1863 ark
"Anadara granosa" = Anadara (Tegillarca) granosa Linnaeus 1758 ark
Anadara craticulata Nyst 1848 ark
Anadara daviesi Mukerjee 1939 ark
Anadara (Lunarca) sp. Gray 1857 ark
 Arcida - Cucullaeidae
Cucullaea "n. sp." Lamarck 1801 clam
 Pectinida - Pectinoidae
"Chlamys (Aequipecten) prototransquebaricus" = Aequipecten
"Chlamys (Aequipecten) prototransquebaricus" = Aequipecten scallop
 Ostreida - Ostreidae
Ostrea "n. sp." Linnaeus 1758 oyster
 Pholadida - Corbulidae
"Corbula (Varicorbula) socialis" = Corbula (Anisocorbula) socialis Martin 1879 clam
 Cardiida - Arcticidae
Arctica sp. Schumacher 1817 clam
 Cardiida - Mactridae
Mactra (Allomactra) "n. sp." Linnaeus 1767 clam
Mactra (Eomactra) "n. sp." Linnaeus 1767 clam
"Mactra (Eomactra) protoreevesii" = Mactra (Mactra) protoreevesii Noetling 1901 clam
 Cardiida - Ungulinidae
 Cardiida - Veneridae
Paphia (Callistotapes) pseudoliratus Vredenburg 1928 venus clam
Pitar "n. sp." Römer 1857 venus clam
Pitar porrecta Koenen 1894 venus clam
Pitar aff. simonnei Dey 1961 venus clam
"Callista (Costacallista) "sp. 1"" = Costacallista Palmer 1926 venus clam
"Callista (Costacallista) sp." = Costacallista Palmer 1926 venus clam
"Callista (Costacallista) "n. sp. 2"" = Costacallista Palmer 1926 venus clam
Callista (Costacallista) splendida Mérian 1860 venus clam
Callista (Costacallista) florida Lamarck 1818 venus clam
Meretrix "n. sp." Lamarck 1799 venus clam
Meretrix persica Cox 1936 venus clam
Clementia protopapyracea Vredenburg 1928 venus clam
 Cardiida - Tellinidae
Apolymetis grimesi tellin clam
 Cardiida - Cardiidae
 Solenida - Pharidae
Ensis "n. sp." Schumacher 1817 clam
 Lucinida - Lucinidae
Lucina pagana Noetling 1901 clam
 Nuculida - Nuculidae
Nucula (Lamellinucula) "n. sp." Schenck 1944 nut clam
 Protobranchia - Nuculanidae
Nuculana virgo Martin 1879 pointed nut clam
 Neogastropoda - Olividae
"Oliva (Anazola) djocdjocarte" = Anazola, Ancilla djocdjocarte, "Ancilla (Sparella) indica" = Ancilla indica, Ancilla (Sparella) birmanica, Oliva indica2
"Oliva (Anazola) djocdjocarte" = Anazola olive snail
"Ancilla (Sparella) indica" = Ancilla indica Vredenburg 1925 olive snail
Ancilla (Sparella) birmanica Vredenburg 1921 olive snail
Oliva indica2 Vredenburg 1925 olive snail
SUBSPECIES: O. (S.) australis indica
 Neogastropoda - Columbellidae
 Neogastropoda - Buccinidae
Siphonalia (Kelletia) subspadicea Vredenburg 1921 true whelk
Cantharus sp. Röding 1798 true whelk
 Neogastropoda - Nassariidae
Nassaria birmanica Vredenburg 1921 snail
Nassarius ovum Martin 1879 snail
 Neogastropoda - Fasciolariidae
Latirus duplicatus Vredenburg 1925 snail
 Neogastropoda - Cancellariidae
"Cancellaria (Bivetopsia) dertonensis" = Bivetopsia
"Cancellaria (Bivetopsia) dertonensis" = Bivetopsia snail
 Neogastropoda - Mitridae
Mitra granatiformis, "Mitra (Chrysome) sowerbyi" = Chrysame sowerbyi
"Mitra (Chrysome) sowerbyi" = Chrysame sowerbyi d'Orbigny 1852 mitre shell
 Neogastropoda - Volutidae
Lyria "n. sp." Gray 1847 volute
 Neogastropoda - Muricidae
"Murex (Chicoreus) arrakensis" = Chicoreus, Murex sp., Murex (Tubicauda) cf. sondeiamus
"Murex (Chicoreus) arrakensis" = Chicoreus murex snail
Murex sp. Linnaeus 1758 murex snail
 Neogastropoda - Mangeliidae
"Mangelia sp." = Cythara (Mangelia)
"Mangelia sp." = Cythara (Mangelia) Loven 1846 snail
 Neogastropoda - Drilliidae
 Neogastropoda - Turridae
Turricula promensis Vredenburg 1921 turrid
Turris (Gemmula) sindiensis Vredenburg 1925 turrid
 Neogastropoda - Conidae
Conus (Leptoconus) bonneti Cossmann 1900 cone shell
Conus (Lithoconus) ineditus Michelotti 1861 cone shell
 Neogastropoda - Terebridae
Duplicaria woodwardiana Martin 1879 auger snail
SUBSPECIES: D. woodwardiana mindegyiensis
"Terebra samarangana" = Terebra (Noditerebra) samarangana Martin 1884 auger snail
"Terebra sp." = Terebra Bruguière 1789 auger snail
"Terebra aff. xoci" = Terebra auger snail
Terebra aff. coxi Dey 1961 auger snail
Terebra promensis Vredenburg 1921 auger snail
SUBSPECIES: T. promensis silistrensis
Terebra perturrita1 Sacco 1891 auger snail
SUBSPECIES: T. subtessellata oligocoenica
"Subula sp." = Terebra Bruguière 1789 auger snail
 Stromboidea - Rostellariidae
"Rimella (Dientomochilus) javana" = Varicospira javana
"Rimella (Dientomochilus) javana" = Varicospira javana Martin 1879 snail
 Ficoidea - Ficidae
Ficus conditus Brongniart 1823 fig shell
SUBSPECIES: F. conditus theoboldi
Ficus cf. conditus Brongniart 1823 fig shell
 Vanikoroidea - Hipponicidae
Hipponix sp. Defrance 1819 hoof shell
 Naticoidea - Naticidae
Natica coxi Mukerjee 1939 moon snail
 Vermetoidea - Vermetidae
Vermetus javanus Martin 1879 worm shell
 Tonnoidea - Ranellidae
Gyrineum bituberculatum, "Gyrineum tuberculatum" = Ranella tubercularis
"Gyrineum tuberculatum" = Ranella tubercularis Risso 1826 triton shell
 Tonnoidea - Bursidae
Bursa elegans frog shell
 Tonnoidea - Cassidae
Semicassis sp. Mörch 1852 snail
 Sorbeoconcha - Turritellidae
"Archimedella (Torculoidella) angulata" = Kapalmerella ranikoti Vredenburg 1928 turret shell
Turritella heberti d'Archiac and Haime 1854 turret shell
SUBSPECIES: T. heberti garoensis
Turritella pinfoldi Vredenburg 1921 turret shell
 Heterostropha - Acteonidae
 Architectonicoidea - Architectonicidae
Architectonica cyclostomum, "Architectonica perspectivum" = Architectonica perspectiva
"Architectonica perspectivum" = Architectonica perspectiva Linnaeus 1767 sundial
 Myliobatiformes - Myliobatidae
Myliobatis sp. Cuvier 1816 eagle ray
 Lamniformes - Lamnidae
Carcharodon sp. Smith 1838 white shark
 Carchariniformes - Carcharhinidae
Galeocerdo cuvieri Peron and LeSueur 1822 tiger shark