Intermareal mediterráneo. Mediteranean Intertidal.

Nos referimos a la Subclase Vetigastropoda (Clase Gastropoda/Filum Mollusca) aceptada por WoRMS.
Vetigastropods are considered to be among the most primitive living gastropods,[2] and are widely distributed in all oceans of the world. Their habitats range from the deep sea to intertidal zones. Many have shells with slits or other secondary openings. One of their main characteristics is the presence of intersected crossed platy shell structure.[3] Most vetigastropods have some bilateral asymmetry of their organ systems.[4]
Vetigastropods range in size from approximately 0.08 in (2 mm) long in the case of Scissurelloidea or Skeneoidea, to more than 11.8 in (300 mm) in length, as with the Haliotoidea. External colours and patterns are typically drab, but such groups as the Tricolioidea and some Trochoidea and Pleurotomarioidea have bright colours and glossy shells. The clade is characterized by having an intersected crossed platy shell structure.[3]

Shells range from elongate turret-shaped structures, to near-spherical. Shell sculpture varies greatly from simple concentric growth lines, which may or may not be barely visible on the shell surface, to heavy radial and axial ribbing. The shell aperture is normally oval, and often tangential to the coiling axis. Most species have an operculum (a small lid-like organ). Within the shell, Vetigastropods have a single pair of cephalic tentacles, and a distinct snout containing the mouth. The lateral sides of the body typically have sensory epipodial tentacles.[5]
https://en.wikipedia.org/wiki/Vetigastropoda less ↑

Nos referimos a la Subclase Caenogastropoda (Clase Gastropoda/Filum Mollusca) aceptada por WoRMS.
Caenogastropoda (from Ancient Greek caeno- meaning "recent") is a taxonomic clade, a large diverse group which are mostly sea snails and other marine gastropod mollusks, but also includes some freshwater snails and some land snails.

Nos referimos a la Subclase Caenogastropoda (Clase Gastropoda/Filum Mollusca).

Caenogastropoda contains many families of shelled marine molluscs – including the periwinkles, cowries, wentletraps, moon snails, murexes, cone snails and turrids – and constitutes about 60% of all living gastropods.[3]

The Caenogastropoda exhibit torsion, and thus are included in what was previously been called the Streptoneura (meaning twisted nerves), also known as Prosobranchia (meaning gills forward). Specifically, they are characterized by having only a single auricle in the heart and a single pair of gill leaflets, and are equivalent to the Monotocardia or Pectinobranchia of older authors.
https://en.wikipedia.org/wiki/Caenogastropoda less ↑

Nos referimos a la Subclase Patellogastropoda (Clase Gastropoda/Filum Mollusca) aceptada por WoRMS. Patellogastropoda have flattened, cone-shaped shells, and the majority of species are commonly found adhering strongly to rocks or other hard substrates. Many limpet shells are covered in microscopic growths of green marine algae, which can make them even harder to see, as they can closely resemble the rock surface itself.

The substance making up the teeth in the radula of limpets is among the strongest biological materials known, with a tensile strength about five times stronger than that of spider silk. The teeth are composed of goethite, an iron-based mineral, woven in a particular way into grouped 1μ thick bundles.[8][9]

Many limpets create a home "scar" on the rock to which they always return between tides, the scar becoming a perfect fit even for the always growing cone-shaped shell and providing excellent protection from predators as well as helping to prevent dehydration, though dehydration remains one of the greatest risks to which these molluscs are exposed and may be why they only survive in temperate waters, not tropical ones where they simply become too hot during low tides. They adhere to the substratum via the adhesion/ suction of the stiffened foot against the rock surface to which it bonds each time with a layer of pedal mucus.[10]

The majority of limpet species have shells that are less than 3 in (8 cm) in maximum length and many are much smaller than that.

A west Mexican limpet species, the giant limpet, Patella mexicana, is known to grow as large as 8 in (20 cm). This species is now in serious danger of extinction, as it is slow to reach maturity, and has suffered from over collecting, both as a food item and by shell collectors and dealers. less ↑

Los gasterópodos, gastrópodos o univalvos (Gastropoda, del griego γαστήρ gaster, "estómago" y ποδη poda, "pie") constituyen la clase más extensa del filo de los Moluscos. Presentan área cefálica (cabeza), un pie musculoso ventral y una concha dorsal (que puede reducirse o hasta perderse en los gasterópodos más evolucionados); además, cuando son larvas, sufren el fenómeno de torsión, que es el giro de la masa visceral sobre el pie y la cabeza. Esto les per less ↑