''Solatisonax cabrali'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of deep-water

sea snail Sea snail is a common name for 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 ...

, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the family Architectonicidae, the staircase shells or sundials.

Taxonomy

The description of ''Solatisonax cabrali'' by Tenório and colleagues, in 2011, was initially based on four young and eroded juvenile shells. The subsequent discovery of two well-preserved empty shells from southeastern Brazil (a juvenile and an adult specimen) brought new information on the species' distribution,

ontogeny Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the egg to adult. The term can also be used to refer to the stu ...

and

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

, which culminated in a redescription by Cavallari and colleagues in 2013. A few mix-ups involving

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

figuration and measurements in the original description were also stressed and rectified in the redescription. ''S. cabrali'' was named after Brazilian government employee Enilson Cabral, an analyst of the Brazilian Institute of Environment and Renewable Natural Resources ( IBAMA) responsible for collecting the materials used in Tenório's study.

Description

''Solatisonax cabrali'' has a small, relatively thick-walled shell, with a maximum known diameter of and up to 5

whorls A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral d ...

. The outer surface of the shell is almost thoroughly ornamented by spiral and axial nodose cords and threads. Its outline changes along the ontogeny, from disk-shaped during the earliest stages of development to depressed cone-shaped in adult specimens. Similarly, the shell's basal region is more inflated than the upper side in younger specimens, but in adult individuals this relationship is inversed. The dome-shaped, inflated

protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called ...

is considered small for an architectonicid as defined by Bieler (1993), ranging from to at 1.5 whorl. It has a glossy surface and a strong terminal

varix A varix (pl. varices) is an abnormally dilated vessel with a tortuous course. Varices usually occur in the venous system, but may also occur in arterial or lymphatic vessels. Examples of varices include: * Varicose veins, large tortuous veins usua ...

marking the protoconch-

teleoconch The gastropod shell is part of the body of a gastropod or snail, 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 ...

transition. Shell color is variable from pale beige to white, with scattered beige spots. Since no living specimens of ''S. cabrali'' were collected to date, the operculum, as well as any details of the animal's soft parts are yet to be described.

Ecology

;Distribution and habitat ''Solatisonax cabrali'' is known only from Brazilian waters, ranging from

Pernambuco Pernambuco () is a state of Brazil, located in the Northeast region of the country. With an estimated population of 9.6 million people as of 2020, making it seventh-most populous state of Brazil and with around 98,148 km², being the 19 ...

and

Alagoas Alagoas (, ) is one of the 27 federative units of Brazil and is situated in the eastern part of the Northeast Region. It borders: Pernambuco (N and NW); Sergipe (S); Bahia (SW); and the Atlantic Ocean (E). Its capital is the city of Maceió. It ...

Rio de Janeiro Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a b ...

and

São Paulo São Paulo (, ; Portuguese for 'Saint Paul') is the most populous city in Brazil, and is the capital of the state of São Paulo, the most populous and wealthiest Brazilian state, located in the country's Southeast Region. Listed by the GaWC a ...

states. It can be found at depths of 230–720 m, usually on sandy and muddy bottoms. The species' range was greatly expanded in the redescription, and includes petroleum extraction sites such as the

Campos Basin The Campos Basin is one of 12 coastal sedimentary basins of Brazil. It spans both onshore and offshore parts of the South Atlantic with the onshore part located near Rio de Janeiro. The basin originated in Neocomian stage of the Cretaceous period ...

References

{{Taxonbar, from=Q14363250 Architectonicidae Gastropods described in 2011