Gastropods, commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda.
Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails that, over evolutionary time, have either entirely lost their shells or have seemingly lost their shells due to having a significantly reduced or internal shell. The name "sea slug" is often applied to nudibranchs and a paraphyletic set of other marine gastropods without apparent shells.
Heterobranchia, the heterobranchs, is a taxonomic clade of snails and slugs, which includes marine, aquatic and terrestrial gastropod mollusks.
The operculum is a corneous or calcareous anatomical structure like a trapdoor that exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc.
Lottia is a genus of sea snails, specifically true limpets, marine gastropod mollusks in the subfamily Lottiinae of the family Lottiidae, one of the families of true limpets.
Sea snails are slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible shell.
Turritellidae, with the common name "tower shells" or "tower snails", is a taxonomic family of small- to medium-sized sea snails, marine gastropod molluscs in the Sorbeoconcha clade.
Ptychodus is a genus of extinct large durophagous (shell-crushing) lamniform sharks from the Cretaceous period, spanning from the Albian to the Campanian. Fossils of Ptychodus teeth are found in many Late Cretaceous marine sediments worldwide.
Clithon is a genus of freshwater snails or brackish snails that have an operculum, aquatic gastropod molluscs in the family Neritidae, the nerites.
Freshwater snails are gastropod mollusks that live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs to major rivers. The great majority of freshwater gastropods have a shell, with very few exceptions. Some groups of snails that live in freshwater respire using gills, whereas other groups need to reach the surface to breathe air. In addition, some are amphibious and have both gills and a lung. Most feed on algae, but many are detritivores and some are filter feeders.
Oncis mortoni is a species of air-breathing sea slug, a shell-less marine pulmonate gastropod mollusk in the family Onchidiidae.
Eatoniella is a genus of minute sea snails, marine gastropod mollusks in the family Eatoniellidae, the eatoniellids.
Platevindex is a genus of air-breathing sea slugs, a shell-less marine pulmonate gastropod mollusks in the family Onchidiidae.
Pseudovermis is genus of minute sea slugs, specifically aolid nudibranchs, marine gastropod mollusks or micromollusks in the family Pseudovermidae.
Laevicardium, common name "egg cockles", is a genus of saltwater clams or cockles, marine bivalve molluscs in the family Cardiidae, the cockles. They are unusual among the cockles in that they have smooth, rounded, "egg-like" valves.
Paleontology in Delaware refers to paleontological research occurring within or conducted by people from the U.S. state of Delaware. There are no local rocks of Precambrian, Paleozoic, Triassic, or Jurassic age, so Delaware's fossil record does not begin until the Cretaceous period. As the Early Cretaceous gave way to the Late Cretaceous, Delaware was being gradually submerged by the sea. Local marine life included cephalopods like Belemnitella americana, and marine reptiles. The dwindling local terrestrial environments were home to a variety of plants, dinosaurs, and pterosaurs. Along with New Jersey, Delaware is one of the best sources of Late Cretaceous dinosaur fossils in the eastern United States. Delaware was still mostly covered by sea water through the Cenozoic era. Local marine life included manatees, porpoises, seals, and whales. Delaware was worked over by glaciers during the Ice Age. The Cretaceous belemnite Belemnitella americana is the Delaware state fossil.
Parvioris is a genus of small ectoparasitic sea snails, marine gastropod mollusks in the family Eulimidae.
Amusium is a genus of scallops, marine bivalve molluscs belonging to the family Pectinidae.
Eatoniella mortoni is a species of marine gastropod mollusc in the family Eatoniellidae. First described by Winston Ponder in 1965, it is endemic to the waters of New Zealand. The species has been used to study the effects of ocean acidification, as it is known to thrive in carbon dioxide-rich environments.
Ocypode mortoni is a small-sized species of Ocypode found in South China and southern Japan. It is closely related to O. stimpsoni which is also found in the same regions, but can be distinguished by the presence of styles on their eyestalks. They also share the same range with O. ceratophthalmus, but O. mortoni have 35 to 71 striae on their stridulating ridges and their smaller claws have broadly rounded to flattened tips.
