| Glycymeris Temporal range: | |
|---|---|
 | |
| Fossil shells of a Glycymeris species from the Upper Pliocene | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Order: | Arcida |
| Family: | Glycymerididae |
| Genus: | Glycymeris da Costa, 1778 |
| Type species | |
| Arca glycymerisLinnaeus, 1758 | |
| Synonyms | |
| |
Glycymeris, common name the bittersweet clams, is a genus of saltwater clams, marine bivalve molluscs in the family Glycymerididae. [1]
The genus name comes from the Ancient Greek word glykymaris (perhaps from Glykys (sweet) and Meris (part)), a word which is only recorded once in Greek literature.
These clams are very common as fossils, from the Cretaceous period in the Valanginian age (between 140.2 ± 3.0 mya and 136.4 ± 2.0 mya). Fossil shells of these molluscs can be found all over the world. Genus Glycymeris includes about 100 extinct species. [2] [3]
The shells are generally biconvex, with equal valves round in outline, and slightly longer than wide. Their size varies from medium to large. The external ligament lacks transverse striations. These clams are a facultatively mobile infaunal suspension feeders.
They are widespread on shallow seabeds that consist of heterogeneous-grained sediments.
Species within this genus include: [4]
Tulip snail or tulip shell is the common name for eight species of large, predatory, subtropical and tropical sea snails from the Western Atlantic. These species are in the genus Fasciolaria. They are marine gastropod mollusks in the family Fasciolariidae, the spindle shells, tulip shells and their allies.
Barbatia is a genus of "bearded" ark clams, marine bivalve mollusks in the family Arcidae, the ark clams.
Buccinum is a genus of medium-sized sea snails, marine gastropod molluscs in the family Buccinidae, the true whelks.
Trochus is a genus of medium-sized to large, top-shaped sea snails with an operculum and a pearly inside to their shells, marine gastropod molluscs in the family Trochidae, the top snails.
Cirsostrema is a genus of very small deepwater sea snails, marine gastropod mollusks in the family Epitoniidae, commonly known as the wentletraps.
Turbo is a genus of large sea snails with gills and an operculum, marine gastropod molluscs in the family Turbinidae, the turban snails.
Pinna is a genus of bivalve molluscs belonging to the family Pinnidae.
Spisula is a genus of medium-sized to large marine bivalve mollusks or clams in the subfazmily Mactrinae of the family Mactridae, commonly known as surf clams or trough shells.
Natica is a genus of small to medium-sized predatory sea snails, marine gastropods in the subfamily Naticinae of the family Naticidae, the moon snails. The genus was erected by Giovanni Antonio Scopoli in 1777.
Crepidula, commonly known as the slipper snails, slipper limpets, or slipper shells, is a genus of sea snails, marine gastropod mollusks in the family Calyptraeidae. This family includes the slipper snails (Crepidula), hat snails (Calyptraea), spiny slipper snails (Bostrycapulus), and cup-and-saucer snails (Crucibulum) as well as Crepipatella, Siphopatella, Grandicrepidula, and Maoricrypta.
Fusinus is a genus of small to large sea snails, marine gastropod mollusks in the family Fasciolariidae, the spindle snails and tulip snails.
Fissurella is a genus of small to medium-sized sea snails or limpets, marine gastropod mollusks in the subfamily Fissurellinae of the family Fissurellidae, the keyhole limpets.
Fusus is a genus of small to large sea snails, marine gastropod mollusks in the family Fasciolariidae, the spindle snails and tulip snails.
Sinum is a genus of predatory sea snails, marine gastropod mollusks in the subfamily Sininae of the family Naticidae, the moon snails.
Phalium, common name the bonnet shells, is a genus of large sea snails, marine gastropod molluscs in the subfamily Phaliinae of the family Cassidae, the helmet shells, bonnet shells and their allies.
Pitar is a genus of saltwater clams, marine bivalve molluscs in the subfamily Callocardiinae of the family Veneridae, the Venus clams. The genus contains over 60 species.
Brachidontes is a genus of mussels in the family Mytilidae.
Tucetona is a genus of saltwater clams, marine bivalve molluscs in the family Glycymerididae, the bittersweet clams. Unlike other genera in the family, Tucetona species have a ribbed shell.