Megatrigoniidae is an extinct family of fossil saltwater clams, marine

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

s in the subclass

Palaeoheterodonta Palaeoheterodonta is a subterclass of bivalve molluscs. It contains the extant orders Unionida (freshwater mussels) and Trigoniida. They are distinguished by having the two halves of the shell be of equal size and shape, but by having the hing ...

. This family of bivalves is known in the fossil record from the

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

period,

Tithonian In the geological timescale, the Tithonian is the latest age (geology), age of the Late Jurassic Epoch and the uppermost stage (stratigraphy), stage of the Upper Jurassic Series. It spans the time between 149.2 ±0.7 annum, Ma and 143.1 ±0.6 (mi ...

age, to the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

period,

Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...

age. Species in this family were facultatively mobile infaunal suspension feeders.

Subfamilies and genera

Subfamilies and genera within the family Megatrigoniidae: * Megatrigoniinae van Hoepen 1929 **'' Anditrigonia'' Levy, 1967 **'' Antutrigonia'' H.A. Leanza & Garate, 1987 **'' Apiotrigonia'' Cox 1952 **'' Bengtsonella'' Cooper & Leanza 2019 **'' Californigonia'' Cooper & Leanza 2019 **'' Columbitrigonia'' Poulton, 1977 **'' Craginella'' Cooper & Leanza 2019 **'' Damborenella'' Cooper & Leanza 2019 **'' Eoanditrigonia'' H.A. Leanza, 1993 **'' Megatrigonia'' van Hoepen, 1929 **'' Paranditrigonia'' Reyes & Pérez, 1983 * Pterotrigoniinae van Hoepen 1929 ** '' Paulckella'' Cooper et al. 1989 ** '' Pterotrigonia'' van Hoepen 1929

Distribution

Fossils of this family have been found in

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India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

and in

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Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...

Serbia , image_flag = Flag of Serbia.svg , national_motto = , image_coat = Coat of arms of Serbia.svg , national_anthem = () , image_map = , map_caption = Location of Serbia (gree ...

and

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and

Yemen Yemen, officially the Republic of Yemen, is a country in West Asia. Located in South Arabia, southern Arabia, it borders Saudi Arabia to Saudi Arabia–Yemen border, the north, Oman to Oman–Yemen border, the northeast, the south-eastern part ...

References

Paleobiology Database
Prehistoric bivalve families Jurassic first appearances Cretaceous extinctions Trigoniida Fossils of Serbia {{paleo-bivalve-stub