Thalassonerita

{{Short description|Genus of gastropods}} {{Speciesbox | fossil_range = {{fossil range|Early Miocene|Recent|Early Miocene<ref name="Kiel 2015">Kiel S. & Hansen B. T. (2015). "Cenozoic Methane-Seep Faunas of the Caribbean Region". ''PLoS ONE'' '''10'''(10): e0140788. {{doi|10.1371/journal.pone.0140788|doi-access=free}}.</ref>-Recent}} | image = | image_caption = | taxon = Thalassonerita naticoidea | parent_authority = Moroni, 1966 | authority = (A. H. Clarke, 1989) | synonyms_ref = <ref name="WoRMS">{{cite WoRMS |title=''Thalassonerita'' Moroni, 1966 |id=1052701 |accessdate=17 December 2023}}</ref> | synonyms = * ''Bathynerita'' {{small|A. H. Clarke, 1989}} * ''Nerita'' (''Thalassonerita'') {{small|Moroni, 1966}} }} '''''Thalassonerita''''' is a monotypic genus of sea snails, marine gastropod mollusks in the family Neritidae. Its sole species is '''''Thalassonerita naticoidea'''''.<ref name="WoRMS"/> ''T. naticoidea'' is endemic to underwater cold seeps in the northern Gulf of Mexico and in the Caribbean.<ref name="Van Gaest 2006">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. http://hdl.handle.net/1794/3717</ref> Originally classified as ''Bathynerita'', the genus was reassessed in 2019 after ''Thalassonerita'' was found to be a senior synonym of ''Bathynerita.''<ref>{{Cite journal |last1=Fukumori |first1=Hiroaki |last2=Yahagi |first2=Takuya |last3=Warén |first3=Anders |last4=Kano |first4=Yasunori |date=2019-01-24 |title=Amended generic classification of the marine gastropod family Phenacolepadidae: transitions from snails to limpets and shallow-water to deep-sea hydrothermal vents and cold seeps |journal=Zoological Journal of the Linnean Society |volume=185 |issue=3 |pages=636–655 |doi=10.1093/zoolinnean/zly078 |issn=0024-4082}}</ref>

== Distribution == [[File:Chemosynthetic_communities_in_the_Gulf_of_Mexico_2006.png|thumb|Chemosynthetic communities in the northern part of Gulf Of Mexico around cold seeps known in 2006 include more than 50 communities.]] ''T. naticoidea'' lives in cold seeps in the northern Gulf of Mexico and in the accretionary wedge of Barbados in the Caribbean<ref name="Van Gaest 20072">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. {{doi|10.1111/j.1439-0485.2006.00147.x}}.</ref> in the upper continental slope, in depths from 400 to 2100 m.<ref name="Van Gaest 20072"/> Minimum recorded depth is 541 m.<ref name="Welch 20102">{{Cite journal |last=Welch |first=John J. |date=2010-01-19 |editor-last=Joly |editor-first=Simon |title=The "Island Rule" and Deep-Sea Gastropods: Re-Examining the Evidence |journal=PLOS ONE |language=en |volume=5 |issue=1 |article-number=e8776 |doi=10.1371/journal.pone.0008776 |issn=1932-6203 |pmc=2808249 |pmid=20098740 |doi-access=free }}</ref> Maximum recorded depth is 1135 m.<ref name="Welch 20102"/>

Examples of localities include:

* "Bush Hill" (27°46.9478 N; 91°30.5266 W)<ref name="Van Gaest 20063">{{Cite thesis |title=Ecology and early life history of BATHYNERITA NATICOIDEA: evidence for long-distance larval dispersal of a cold seep gastropod |url=https://scholarsbank.uoregon.edu/xmlui/handle/1794/3717 |date=2006 |degree=Thesis |language=en-US |first=Van |last=Gaest}}</ref> * methane seep "Brine Pool NR-1" in depth 650 m (27°43.415 N; 91°16.756 W)<ref name="Van Gaest 20072"/> * GC 234 (27°44.7318 N; 91°13.4355 W)<ref name="Van Gaest 20063"/> * MC 929<ref name="Van Gaest 20063"/>

== Description == ''T. naticoidea'' has a shell that can be closed with a calcareous operculum. The round shell is low-spired and smoothly sculptured. Its aperture has roughly a semicircular shape. The maximum recorded shell length is 16&nbsp;mm.<ref name="Welch 20102"/>

== Ecology == [[File:Bathymodiolus_childressi.jpg|thumb|The mussel species ''Bathymodiolus childressi'', with which ''T. naticoidea'' is often associated]]

=== Habitat === ''T. naticoidea'' lives at deep-sea cold seeps where hydrocarbons (oil and methane) are leaking out of the seafloor. ''T. naticoidea'' is the most numerous gastropod species in its area.<ref name="Van Gaest 20072"/><ref name="Zande 1999">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. [https://www.jstor.org/stable/3226912 JSTOR]</ref><ref name="Hodgson 1998">{{Cite journal |last1=Hodgson |first1=Alan N. |last2=Eckelbarger |first2=Kevin J. |last3=Young |first3=Craig M. |date=1998 |title=Sperm Morphology and Spermiogenesis in the Methane-Seep Mollusc Bathynerita naticoidea (Gastropoda: Neritacea) from the Louisiana Slope |journal=Invertebrate Biology |volume=117 |issue=3 |pages=199–207 |doi=10.2307/3226986 |jstor=3226986 |issn=1077-8306}}</ref> They have also been found near a brine pool seep in the Gulf of Mexico.<ref name="Van Gaest 20072" /><ref name="Van Gaest 20063" /> ''T. naticoidea'' cannot move over mud or on soft sediments,<ref>Van Gaest A. L. "[http://www.ridge2000.org/SEAS/for_students/reference/scientist_spotlight/slideshow_avgaest.php?slide=3 Larval ecology of deep-sea snails.] {{Webarchive|url=https://web.archive.org/web/20101128102936/http://ridge2000.org/SEAS/for_students/reference/scientist_spotlight/slideshow_avgaest.php?slide=3|date=2010-11-28}} (slide 3)". accessed 1 May 2010.</ref> and usually lives on beds of ''Bathymodiolus childressi'' mussels.<ref name="Dattagupta 2007">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. {{doi|10.1111/j.1439-0485.2006.00130.x}}</ref> ''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.<ref name="Dattagupta 2007" />

As a euryhaline species, these snails normally live in saline water. Their preferred salinity is 30-50 ‰, and although they can survive salinity as high as 85 ‰, they actively avoid brine with salinity over 60 ‰.<ref name="Van Gaest 20072" /><ref name="Van Gaest 20063"/> They usually move upward in natural conditions, where the concentration of salt is lower.<ref name="Van Gaest 20072" /> ''T. naticoidea'' has no osmoregulatory ability when the salinity is too high,<ref name="Van Gaest 20072" /> but it can survive high salinities, because it closes its operculum.<ref name="Van Gaest 20072" />

=== Feeding habits === ''T. naticoidea'' feeds on periphyton of methanotrophic bacteria that grow on shells of mussels of ''B. childressi;'' the decomposing periostracum of these mussels; their byssal fibers; and their detritus.<ref name="Van Gaest 20072" /><ref name="Dattagupta 2007" />

=== Life cycle === Oogenesis and formation of yolk (vitellogenesis) of ''T. naticoidea'' was described by Eckelbarger & Young (1997).<ref name="Eckelbarger 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. [https://www.jstor.org/stable/3226862 JSTOR].</ref> This was the first ultrastructural description of formation of yolk in today's clade Neritimorpha.<ref name="Eckelbarger 1997" /> This process is similar to other gastropods.<ref name="Eckelbarger 1997" />

Spermatogenesis of ''T. naticoidea'' was described by Hodgson et al. (1998).<ref name="Hodgson 1998" /> ''T. naticoidea'' has sperm (eusperm) of introsperm type (about 90&nbsp;μm long and filiform),<ref name="Hodgson 1998" /> so it can be presumed, that the fertilisation of ''T. naticoidea'' is internal.<ref name="Hodgson 1998" />

Eggs are laid in round and white-rimmed egg capsules on various hard substrata:<ref name="Van Gaest 20063" /> the dorsal part of the shells of the mussel ''Bathymodiolus childressi''.<ref name="Gustafson 1998">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'' '''40'''(1-2): [https://archive.org/stream/malacologia401998inst#page/62/mode/1up 63]-112. [https://archive.org/stream/malacologia401998inst#page/90/mode/2up/ page 90] and page 96.</ref> They were found also on shells of mussel ''Tamu fisheri''.<ref name="Gustafson 1998" /> There are then scars from these egg capsules on these mussels.<ref name="Gustafson 1998" /> Highest number of eggs are laid from December to February.<ref name="Van Gaest 20063" /> Eggs are 135-145 μm in diameter.<ref name="Van Gaest 20063" /> There are 25-180 eggs in one eggs capsule.<ref name="Van Gaest 20063" /> The length of the egg capsule ranges from 1.2 to 2.9&nbsp;mm.<ref name="Van Gaest 20063" />

During the development of the embryo, the egg capsule is changing color from creamy ivory color to dark purple color.<ref name="Van Gaest 20063" /> The cleavage is holoblastic spiral cleavage as in other gastropods.<ref name="Van Gaest 20063" />

Veliger larvae are hatched from eggs after four months of development from May to early July.<ref name="Van Gaest 20063" /> Veliger is about 170 μm long (120-278 μm).<ref name="Van Gaest 20063" /> Veligers feed on plankton (planktotrophic)<ref name="Van Gaest 20063" /> and they are probably obligate planktotrophs. They can swim with ciliated foot and they are swimming probably for at least eight months.<ref name="Van Gaest 20063" /> Veliger have pigmented eyespots.<ref name="Van Gaest 20063" /> Maybe the same chemosensory mechanisms for detecting mussel beds can be used by its larvae.<ref name="Dattagupta 2007" /> Veliger in size 600-700 μm can undergo metamorphosis into a snail.<ref name="Dattagupta 2007" /> Only two protoconchs are known to be found ''in situ'' and they measured 630 μm and 615 μm in length.<ref name="Van Gaest 20063" />

=== Interspecific relationships === There lives a fungal filamentous ascomycete (phylum Ascomycota) species as a commensal on the gills of ''T. naticoidea''.<ref name="Zande 1999" /> These fungi are externally attached to cells of gills.<ref name="Zande 1999" /> When this discovery was published in 1999, it was the first such association between fungus and gastropod from underwater seep community.<ref name="Zande 1999" /> The origin and function of this association is unknown.<ref name="Zande 1999" />

There are no known bacterial symbionts with ''T. naticoidea'' (1999).<ref name="Zande 1999" />

Other animals living in communities with ''T. naticoidea'' include:

* polychaete ''Methanoaricia dendrobranchiata'' from family Orbiniidae<ref name="Van Gaest 20072" /> * mussels ''Bathymodiolus childressi'' from family Mytilidae<ref name="Van Gaest 20072" />

== Genetics == Partial genetic sequences of mitochondrion of ''T. naticoidea'' were published in 1996<ref name="McArthur 1996">McArthur A. G. (1996). "Molecular investigation of the evolutionary origins of hydrothermal vent gastropods". Thesis, University of Victoria, Canada.</ref> and in 2008:<ref name="Frey 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'' '''48'''(3): 1067-1086. {{doi|10.1016/j.ympev.2008.05.009}}</ref>

* 28S ribosomal RNA<ref name="McArthur 1996" /><ref>{{Cite journal |date=1996-12-21 |title=Bathynerita naticoides 28S ribosomal RNA gene, partial sequence |url=https://www.ncbi.nlm.nih.gov/nuccore/U75844.1 |language=en-US}}</ref><ref>{{Cite journal |date=1996-12-11 |title=Bathynerita naticoides 28S ribosomal RNA gene, partial sequence |url=https://www.ncbi.nlm.nih.gov/nuccore/U78647.1 |language=en-US}}</ref> * cytochrome-c oxidase I (COI) gene<ref name="Frey 2008" /><ref>{{Cite journal |date=2016-07-26 |title=Bathynerita naticoidea isolate GM.1 cytochrome oxidase subunit I (COI) gene, partial cds; mitochondrial |url=https://www.ncbi.nlm.nih.gov/nuccore/EU732361.1 |language=en-US}}</ref> * 16S ribosomal RNA<ref name="Frey 2008" /><ref>{{Cite journal |date=2008-09-04 |title=Bathynerita naticoidea isolate GM.1 16S large subunit ribosomal RNA gene, partial sequence; mitochondrial |url=https://www.ncbi.nlm.nih.gov/nuccore/EU732198.1 |language=en-US}}</ref>

== Further reading ==

* Carney R. S. (1993). caption 7: "Heterotrophic Megafauna of Chemosynthetic Seep Ecosystems". In: U.S. Dept. of the Interior, Minerals Management Service. (1993). ''Chemosynthetic Ecosystems Studies Interim Report''. Prepared by Geochemical and Environmental Research Group. U. S. Dept. of the Interior, Minerals Mgmt. Service, Gulf of Mexico OCS Regional Office, New Orleans, LA, 110 pp. [https://web.archive.org/web/20100528175120/http://www.gomr.mms.gov/PI/PDFImages/ESPIS/3/3620.pdf PDF] * Zande J. M. & Carney R. S. (2001). "Population size structure and feeding biology of ''Bathynerita naticoidea'' Clarke 1989 (Gastropoda: Neritacea) from Gulf of Mexico hydrocarbon seeps". ''Gulf of Mexico Science'' [https://web.archive.org/web/20110726000352/http://goms.disl.org/tocpages/december2001vol19no2.htm '''19'''(2)]: 107–118.

==References== {{reflist}}

{{Taxonbar|from=Q4869196}}

Category:Phenacolepadidae Category:Monotypic gastropod genera