''Thalassonerita'' is a monotypic

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

s, marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

s in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Neritidae Neritidae, common name the nerites, is a Taxonomy (biology), taxonomic Family (biology), family of small to medium-sized saltwater and freshwater snails which have a gill and a distinctive Operculum (gastropod), operculum. MolluscaBase eds. (202 ...

. Its sole species is ''Thalassonerita naticoidea''. ''T. naticoidea'' is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to underwater

cold seep A cold seep (sometimes called a cold vent) is an area of the ocean floor where seepage of fluids rich in hydrogen sulfide, methane, and other hydrocarbons occurs, often in the form of a brine pool. ''Cold'' does not mean that the temperature ...

s in the northern

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

and in the

Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America ...

.Van Gaest A. L. (2006). "Ecology and early life history of ''Bathynerita naticoidea'': evidence for long-distance larval dispersal of a cold seep gastropod". Thesis. Department of Biology and the Graduate School of the

University of Oregon The University of Oregon (UO, U of O or Oregon) is a Public university, public research university in Eugene, Oregon, United States. Founded in 1876, the university is organized into nine colleges and schools and offers 420 undergraduate and gra ...

. http://hdl.handle.net/1794/3717 Originally classified as ''Bathynerita'', the genus was reassessed in 2019 after ''Thalassonerita'' was found to be a senior synonym of ''Bathynerita.''

Distribution

Chemosynthetic_communities_in_the_Gulf_of_Mexico_2006

''T. naticoidea'' lives in cold seeps in the northern Gulf of Mexico and in the

accretionary wedge An accretionary wedge or accretionary prism forms from sediments accreted onto the non- subducting tectonic plate at a convergent plate boundary. Most of the material in the accretionary wedge consists of marine sediments scraped off from the ...

Barbados Barbados, officially the Republic of Barbados, is an island country in the Atlantic Ocean. It is part of the Lesser Antilles of the West Indies and the easternmost island of the Caribbean region. It lies on the boundary of the South American ...

in the

Van Gaest A. L., Young C. M., Young J. J., Helms A. R. & Arellano S. M. (). "Physiological and behavioral responses of ''Bathynerita naticoidea'' (Gastropoda: Neritidae) and ''Methanoaricia dendrobranchiata'' (Polychaeta: Orbiniidae) to hypersaline conditions at a brine pool cold seep. ''Marine Ecology'' 28(1): 199 - 207. . in the upper

continental slope A continental margin is the outer edge of continental crust abutting oceanic crust under coastal waters. It is one of the three major zones of the ocean floor, the other two being deep-ocean basins and mid-ocean ridges. The continental margi ...

, in depths from 400 to 2100 m. Minimum recorded depth is 541 m. Maximum recorded depth is 1135 m. Examples of localities include: * "Bush Hill" (27°46.9478 N; 91°30.5266 W) * methane seep "Brine Pool NR-1" in depth 650 m (27°43.415 N; 91°16.756 W) * GC 234 (27°44.7318 N; 91°13.4355 W) * MC 929

Description

''T. naticoidea'' has a

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses Science Biology * Seashell, a hard outer layer of a marine ani ...

that can be closed with a calcareous operculum. The round shell is low-spired and smoothly sculptured. Its

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

has roughly a semicircular shape. The maximum recorded

length is 16 mm.

Ecology

Habitat

''T. naticoidea'' lives at deep-sea

cold seeps A cold seep (sometimes called a cold vent) is an area of the ocean floor where seepage of fluids rich in hydrogen sulfide, methane, and other hydrocarbons occurs, often in the form of a brine pool. ''Cold'' does not mean that the temperature o ...

where hydrocarbons (oil and methane) are leaking out of the seafloor. ''T. naticoidea'' is the most numerous gastropod species in its area.Zande J. M. (1999). "An Ascomycete Commensal on the Gills of ''Bathynerita naticoidea'', the Dominant Gastropod at Gulf of Mexico Hydrocarbon Seeps". ''Invertebrate Biology'' 118(1): 57-62
JSTOR
/ref> They have also been found near a brine pool seep in the Gulf of Mexico. ''T. naticoidea'' cannot move over mud or on soft sediments, and usually lives on beds of ''

Bathymodiolus childressi ''Bathymodiolus childressi'' is a species of deepwater mussel, a marine bivalve mollusk species in the family Mytilidae, the mussels. Although this species has been known since 1985,Childress J.J., Fisher C.R., Brooks J.M., Kennicutt M.C., II, ...

'' mussels.Dattagupta S., Martin J., Liao S., Carney R. S. & Fisher C. R. (2007). "Deep-sea hydrocarbon seep gastropod ''Bathynerita naticoidea'' responds to cues from the habitat-providing mussel ''Bathymodiolus childressi''". ''Marine Ecology'' 28(1): 193-198. ''T. naticoidea'' can detect beds of ''B. childressi'', because it is attracted by a water altered by this species of mussel, although the nature of the attractant is unknown. As a

euryhaline Euryhaline organisms are able to adapt to a wide range of salinities. An example of a euryhaline fish is the short-finned molly, '' Poecilia sphenops'', which can live in fresh water, brackish water, or salt water. The green crab ('' Carcinus m ...

species, these snails normally live in

saline water Saline water (more commonly known as salt water) is water that contains a high concentration of dissolved salts (mainly sodium chloride). On the United States Geological Survey (USGS) salinity scale, saline water is saltier than brackish wat ...

. Their preferred

salinity Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensio ...

is 30-50 ‰, and although they can survive salinity as high as 85 ‰, they actively avoid

brine Brine (or briny water) is a high-concentration solution of salt (typically sodium chloride or calcium chloride) in water. In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawat ...

with salinity over 60 ‰. They usually move upward in natural conditions, where the concentration of salt is lower. ''T. naticoidea'' has no osmoregulatory ability when the salinity is too high, but it can survive high salinities, because it closes its operculum.

Feeding habits

''T. naticoidea'' feeds on

periphyton Periphyton is a complex mixture of algae, cyanobacteria, heterotrophic microbes, and detritus that is attached to submerged surfaces in most aquatic ecosystems. The related term Aufwuchs ( German "surface growth" or "overgrowth", ) refers to the ...

methanotrophic Methanotrophs (sometimes called methanophiles) are prokaryotes that metabolize methane as their source of carbon and chemical energy. They are bacteria or archaea, can grow aerobically or anaerobically, and require single-carbon compounds to ...

bacteria that grow on shells of mussels of ''B. childressi;'' the decomposing

periostracum The periostracum ( ) is a thin, organic coating (or "skin") that is the outermost layer of the shell of many shelled animals, including molluscs and brachiopods. Among molluscs, it is primarily seen in snails and clams, i.e. in gastropods an ...

of these mussels; their byssal fibers; and their

detritus In biology, detritus ( or ) is organic matter made up of the decomposition, decomposing remains of organisms and plants, and also of feces. Detritus usually hosts communities of microorganisms that colonize and decomposition, decompose (Reminera ...

Life cycle

Oogenesis Oogenesis () or ovogenesis is the differentiation of the ovum (egg cell) into a cell competent to further develop when fertilized. It is developed from the primary oocyte by maturation. Oogenesis is initiated before birth during embryonic devel ...

and formation of yolk (

vitellogenesis Vitellogenesis is the process of yolk protein formation in the oocytes during sexual maturation. The term ''vitellogenesis'' comes from the Latin language, Latin ''vitellus'' ("egg yolk"). Yolk proteins, such as lipovitellin and phosvitin, provid ...

) of ''T. naticoidea'' was described by Eckelbarger & Young (1997).Eckelbarger K. J. & Young C. M. (1997). "Ultrastructure of the ovary and oogenesis in the methane-seep mollusc, ''Bathynerita naticoidea'' (Gastropoda: Neritidae) from the Louisiana slope". ''Invertebrate Biology'' 116: 299-312
JSTOR
This was the first ultrastructural description of formation of yolk in today's clade

Neritimorpha Neritimorpha is a clade of gastropod molluscs that contains around 2,000 extant species of sea snails, limpets, freshwater snails, land snails and slugs. This clade used to be known as the superorder Neritopsina. Etymology The clade’s name, N ...

. This process is similar to other gastropods.

Spermatogenesis Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testicle. This process starts with the Mitosis, mitotic division of the stem cells located close to the basement membrane of ...

of ''T. naticoidea'' was described by Hodgson et al. (1998). ''T. naticoidea'' has

sperm Sperm (: sperm or sperms) is the male reproductive Cell (biology), cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm ...

( eusperm) of introsperm type (about 90 μm long and filiform), so it can be presumed, that the

fertilisation Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a zygote and initiate its development into a new individual organism or of ...

of ''T. naticoidea'' is

internal Internal may refer to: *Internality as a concept in behavioural economics *Neijia, internal styles of Chinese martial arts *Neigong or "internal skills", a type of exercise in meditation associated with Daoism * ''Internal'' (album) by Safia, 2016 ...

. Eggs are laid in round and white-rimmed egg capsules on various hard substrata: the dorsal part of the shells of the mussel ''Bathymodiolus childressi''.Gustafson R. G., Turner R. D., Lutz R. A. & Vrijenhoek R. C. (1998). "A new genus and five new species of mussels (Bivalvia, Mytilidae) from deep-sea sulfide/hydrocarbon seeps in the Gulf of Mexico". ''

Malacologia ''Malacologia'' is a peer-reviewed scientific journal in the field of malacology, the study of mollusks. The journal publishes articles in the fields of molluscan systematics, ecology, population ecology, genetics, molecular genetics, evolution, an ...

'' 40(1-2)
63
112
page 90
and page 96. They were found also on shells of mussel '' Tamu fisheri''. There are then scars from these egg capsules on these mussels. Highest number of eggs are laid from December to February. Eggs are 135-145 μm in diameter. There are 25-180 eggs in one eggs capsule. The length of the egg capsule ranges from 1.2 to 2.9 mm. During the development of the embryo, the egg capsule is changing color from creamy ivory color to dark purple color. The cleavage is holoblastic spiral cleavage as in other gastropods.

Veliger A veliger is the planktonic larva of many kinds of sea snails and freshwater snails, as well as most bivalve molluscs (clams) and tusk shells. Description The veliger is the characteristic larva of the gastropod, bivalve and scaphopod taxono ...

larvae are hatched from eggs after four months of development from May to early July. Veliger is about 170 μm long (120-278 μm). Veligers feed on

plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...

(planktotrophic) and they are probably obligate planktotrophs. They can swim with ciliated foot and they are swimming probably for at least eight months. Veliger have pigmented eyespots. Maybe the same

chemosensory A chemoreceptor, also known as chemosensor, is a specialized sensory receptor which transduces a chemical substance (endogenous or induced) to generate a biological signal. This signal may be in the form of an action potential, if the chemorecept ...

mechanisms for detecting mussel beds can be used by its larvae. Veliger in size 600-700 μm can undergo metamorphosis into a snail. Only two

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 " ...

s are known to be found ''

in situ is a Latin phrase meaning 'in place' or 'on site', derived from ' ('in') and ' ( ablative of ''situs'', ). The term typically refers to the examination or occurrence of a process within its original context, without relocation. The term is use ...

'' and they measured 630 μm and 615 μm in length.

Interspecific relationships

There lives a fungal filamentous

ascomycete Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The def ...

(phylum

Ascomycota Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The def ...

) species as a

commensal Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit f ...

on the

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

of ''T. naticoidea''. These fungi are externally attached to cells of gills. When this discovery was published in 1999, it was the first such association between fungus and gastropod from underwater seep community. The origin and function of this association is unknown. There are no known bacterial

symbiont Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biological interaction, between two organisms of different species. The two organisms, termed symbionts, can fo ...

s with ''T. naticoidea'' (1999). Other animals living in communities with ''T. naticoidea'' include: *

polychaete Polychaeta () is a paraphyletic class of generally marine Annelid, annelid worms, common name, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called c ...

'' Methanoaricia dendrobranchiata'' from family

Orbiniidae Orbiniidae is a family of polychaete worms. Orbiniids are mostly unselective deposit feeders on marine detritus. They can be found from the neritic zone to abyssal depths. The family was revised in 1957 by Olga Hartman and some further revisi ...

* mussels ''

'' from family

Mytilidae The Mytilidae are a family (biology), family of small to large Marine life, marine and Brackish water, brackish-water bivalve molluscs in the order (biology), order Mytilida. One of the genera, ''Limnoperna fortunei, Limnoperna'', even inhabits f ...

Genetics

Partial

genetic sequence Genetic may refer to: *Genetics, in biology, the science of genes, heredity, and the variation of organisms **Genetic, used as an adjective, refers to genes *** Genetic disorder, any disorder caused by a genetic mutation, whether inherited or de no ...

s of

mitochondrion A mitochondrion () is an organelle found in the cell (biology), cells of most eukaryotes, such as animals, plants and fungi. Mitochondria have a double lipid bilayer, membrane structure and use aerobic respiration to generate adenosine tri ...

of ''T. naticoidea'' were published in 1996McArthur A. G. (1996). "Molecular investigation of the evolutionary origins of hydrothermal vent gastropods". Thesis, University of Victoria, Canada. and in 2008:Frey M. A. & Vermeij G. J. (2008). "Molecular phylogenies and historical biogeography of a circumtropical group of gastropods (Genus: Nerita): implications for regional diversity patterns in the marine tropics". ''

Molecular Phylogenetics and Evolution ''Molecular Phylogenetics and Evolution'' is a peer-reviewed scientific journal of evolutionary biology and phylogenetics. The journal is edited by E.A. Zimmer. Indexing The journal is indexed in: * EMBiology *Journal Citation Reports *Scopus ...

'' 48(3): 1067-1086. *

28S ribosomal RNA 28S ribosomal RNA is the structural ribosomal RNA (rRNA) for the large subunit (LSU) of eukaryotic cytoplasmic ribosomes, and thus one of the basic components of all eukaryotic cells. It has a size of 25S in plants and 28S in mammals, hence th ...

* cytochrome-c oxidase I (COI) gene *

16S ribosomal RNA 16S ribosomal RNA (or 16 S rRNA) is the RNA component of the 30S subunit of a prokaryotic ribosome ( SSU rRNA). It binds to the Shine-Dalgarno sequence and provides most of the SSU structure. The genes coding for it are referred to as 16S ...

References

{{Taxonbar, from=Q4869196 Phenacolepadidae Monotypic gastropod genera