Yecua Formation | |
---|---|
Stratigraphic range: Late Langhian-Early Messinian (Colloncuran-Huayquerian) ~ | |
Underlies | Tariquia Formation |
Overlies | Petaca Formation |
Thickness | ~50–300 m (160–980 ft) |
Lithology | |
Primary | Mudstone, Sandstone[1] |
Other | Gypsum |
Location | |
Region | Chaco Basin |
Country | ![]() |
The Yecua Formation is a geological Formation in what is now Bolivia. Studies suggest that the Yecua Formation preserves a coastal setting with humid to semiarid floodplains, shorelines and tidal as well as shallow marine environments including marshes, streams, lakes and brackish bodies of water. There may have been a connection to the Amazon Basin or the Paranaense Sea.[2]
Name | Species | Member | Material | Notes |
---|---|---|---|---|
Tellina[1] | T. sp | |||
cf. Cyrena[1] | cf. C. sp | |||
cf. Astarte[1] | cf. A. sp | |||
cf. Lucina[1] | cf. L. sp | |||
Senis[1] | S. cf. elongatus | |||
cf. Corbula or Cymbophora sp.[1] | cf. C. sp | |||
cf. Nucula[1] | cf. N. sp |
Name | Species | Member | Material | Notes |
---|---|---|---|---|
cf. Gyrodes or Natica sp.[1] | ||||
cf. Turritella[1] | cf. T. sp |
Name | Species | Member | Material | Notes |
---|---|---|---|---|
Bythocypris[1] | B. sp | |||
Cyprideis[1] | C. sp | |||
cf. Balanus[1] | cf. B. sp | |||
indetermined crabs [1] |
Name | Species | Member | Material | Notes | Image |
---|---|---|---|---|---|
cf. Theosodon[1] | cf. T. sp | distal limb bone | a litoptern | ![]() | |
Rodentia indet.[1] | tooth | ||||
Mourasuchus[3] | M. sp. | skull fragments, partial vertebrae & ribs | |||
Pleurodira[3] | shell elements | ||||
Humboldtichthys[4] | Humboldtichthys kirschbaumi | incompletely preserved anterior portion of the body and posterior head | a Glass Knifefish | ||
Siluriformes indet.[1] | possibly Ariidae | ||||
Characiformes or Clupeiformes[1] | a scale |