Gastropod shellThe gastropod shell is part of the body of many gastropods, including snails, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or in some cases the shell is reduced such that the body cannot be retracted within it (semi-slug).
Aperture (mollusc)The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where the head-foot part of the body of the animal emerges for locomotion, feeding, etc. The term aperture is used for the main opening in gastropod shells, scaphopod shells, and also for Nautilus and ammonite shells. The word is not used to describe bivalve shells, where a natural opening between the two shell valves in the closed position is usually called a gape.
Spire (mollusc)A spire is a part of the coiled shell of molluscs. The spire consists of all of the whorls except for the body whorl. Each spire whorl represents a rotation of 360°. A spire is part of the shell of a snail, a gastropod mollusc, a gastropod shell, and also the whorls of the shell in ammonites, which are fossil shelled cephalopods. In textbook illustrations of gastropod shells, the tradition (with a few exceptions) is to show most shells with the spire uppermost on the page.
SeagrassMarine flowering plantsSeagrasses are the only embryophytes (commonly referred to as "land plants") which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the order Alismatales (in the clade of monocotyledons). Seagrasses evolved from terrestrial plants which recolonised the ocean 70 to 100 million years ago.
Intertidal zoneThe intertidal zone, or foreshore, is the area above water level at low tide and underwater at high tide; in other words, it is the part of the littoral zone within the tidal range. This area can include several types of habitats with various species of life, such as sea stars, sea urchins, and many species of coral with regional differences in biodiversity. Sometimes it is referred to as the littoral zone or seashore, although those can be defined as a wider region.
CaenogastropodaCaenogastropoda is a taxonomicsubclass of molluscs in the class Gastropoda. It is a large diverse group which are mostly sea snails and other marinegastropodmollusks, but also includes some freshwater snails and some land snails. The subclass is the most diverse and ecologically successful of the gastropods.
Nervous systemIn biology, the nervous system is the highly complex part of an animal that coordinates its actions and sensoryinformation by transmitting signals to and from different parts of its body. The nervous system detects environmental changes that impact the body, then works in tandem with the endocrine system to respond to such events. Nervous tissue first arose in wormlike organisms about 550 to 600 million years ago.OvipositorThe ovipositor is a tube-like organ used by some animals, especially insects, for laying eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typically its form is adapted to functions such as preparing a place for the egg, transmitting the egg, and then placing it.
TropicsThe tropics are the region of Earth surrounding the equator, where the Sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. Because of Earth's axial tilt, the width of the tropics (in latitude) is twice the tilt. The tropics are also referred to as the tropical zone and the torrid zone (see geographical zone).
Taxonomic rankIn biological taxonomy, a taxonomic rank denotes the level that a group of organisms—either taxon or clade—occupies in a hierarchical system of classification, which is usually but not necessarily based on evolutionary relationships between those organisms.
GastropodGastropods (; previously known as Univalves; class Gastropoda) are a vast and diverse group of invertebrates within the phylum Mollusca, comprising the animals commonly known as snails and slugs. With an estimated 65,000 to 80,000 living species, they form the second-largest animal class after the insects. The fossil record of gastropods extends back to the Late Cambrian.Fresh waterFresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mineral-rich waters, such as chalybeate springs.
EstuaryAn estuary is a partially enclosed coastal body of brackish water where freshwater from rivers or streams meets and mixes with saltwater from the open sea. Estuaries form transition zones between riverine and marine environments and are classified as ecotones, areas where different ecosystems overlap. They are influenced by both marine processes (such as tides, waves, and saline water intrusion) and fluvial processes (including freshwater flow and sediment input).*As an Amazon Associate I earn from qualifying purchases.