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Lucinidae

Lucinidae
Temporal range: Silurian – Present
Divaricella huttoniana
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia
Order: Lucinida
Superfamily: Lucinoidea
Family: Lucinidae
Fleming, 1828
Genera

See text.

Lucinidae, common name hatchet shells, is a family of saltwater clams, marine bivalve molluscs.

These bivalves are remarkable for their endosymbiosis with sulphide-oxidizing bacteria.[1]

Characteristics

The members of this family have a worldwide distribution. They are found in muddy sand or gravel at or below low tide mark. But they can also be found at bathyal depths. They have characteristically rounded shells with forward-facing projections. The shell is predominantly white and buff and is often thin-shelled. The shells are equivalve with unequal sides. The umbones (the apical part of each valve) are just anterior to mid-line. The adductor scars are unequal: the anterior are narrower and somewhat longer than the posterior. They are partly or largely separated from the pallial line. The valves are flattened and etched with concentric or radial rings. Each valve bears two cardinal and two plate-like lateral teeth. These molluscs do not have siphons but the extremely long foot makes a channel which is then lined with slime and serves for the intake and expulsion of water. The ligament is external and is often deeply inset. The pallial line lacks a sinus.[2]

Fossil record

An Eocene species Superlucina megameris was the largest lucinid ever recorded, with shell size up to 31.1 centimetres (12.2 in) high, over 28 centimetres (11 in) wide and 8.6 centimetres (3.4 in) thick.[3]

Symbiosis

Lucinids host their sulfur-oxidizing symbionts in specialized gill cells called bacteriocytes.[4] Lucinids are burrowing bivalves that live in environments with sulfide-rich sediments.[5] The bivalve will pump sulfide-rich water over its gills from the inhalant siphon in order to provide symbionts with sulfur and oxygen.[5] The endosymbionts then use these substrates to fix carbon into organic compounds, which are then transferred to the host as nutrients.[6] During periods of starvation, lucinids may harvest and digest their symbionts as food.[6]

Symbionts are acquired via phagocytosis of bacteria by bacterioctyes.[7] Symbiont transmission occurs horizontally, where juvenile lucinids are aposymbiotic and acquire their symbionts from the environment in each generation.[8] Lucinids maintain their symbiont population by reacquiring sulfur-oxidizing bacteria throughout their lifetime.[9] Although process of symbiont acquisition is not entirely characterized, it likely involves the use of the binding protein, codakine, isolated from the lucinid bivalve, Codakia orbicularis.[10] It is also known that symbionts do not replicate within bacteriocytes because of inhibition by the host. However, this mechanism is not well understood.[9]

Lucinid bivalves originated in the Silurian; however, they did not diversify until the late Cretaceous, along with the evolution of seagrass meadows and mangrove swamps.[11] Lucinids were able to colonize these sulfide rich sediments because they already maintained a population of sulfide-oxidizing symbionts. In modern environments, seagrass, lucinid bivalves, and the sulfur-oxidizing symbionts constitute a three-way symbiosis. Because of the lack of oxygen in coastal marine sediments, dense seagrass meadows produce sulfide-rich sediments by trapping organic matter that is later decomposed by sulfate-reducing bacteria.[12] The lucinid-symbiont holobiont removes toxic sulfide from the sediment, and the seagrass roots provide oxygen to the bivalve-symbiont system.[12]

The symbionts from at least two species of lucinid clams, Codakia orbicularis and Loripes lucinalis, are able to fix nitrogen gas into organic nitrogen.[13][14]

Genera

The following genera are recognised in the family Lucinidae:[15]

Subfamily Codakiinae Iredale, 1937
Subfamily Fimbriinae Nicol, 1950
Subfamily Leucosphaerinae J. D. Taylor & Glover, 2011
Subfamily Lucininae J. Fleming, 1828
Subfamily Milthinae Chavan, 1969
Subfamily Monitilorinae J. D. Taylor & Glover, 2011
Subfamily Myrteinae Chavan, 1969
Subfamily Pegophyseminae J. D. Taylor & Glover, 2011
Incertae sedis (Subfamily not yet assigned )

References

  1. ^ Taylor, J. D.; Glover, E. A. (2006-11-24). "Lucinidae (Bivalvia) - the most diverse group of chemosymbiotic molluscs". Zoological Journal of the Linnean Society. 148 (3): 421–438. doi:10.1111/j.1096-3642.2006.00261.x. ISSN 0024-4082.
  2. ^ Barrett, J. H. and C. M. Yonge, 1958. Collins Pocket Guide to the Sea Shore. P. 161. Collins, London
  3. ^ George R. McGhee Jr. (2019). Convergent Evolution on Earth. Lessons for the Search for Extraterrestrial Life. MIT Press. pp. 67–68. ISBN 978-0-262-35418-9. Retrieved 2022-08-23.
  4. ^ Roeselers, Guus; Newton, Irene L. G. (2012-02-22). "On the evolutionary ecology of symbioses between chemosynthetic bacteria and bivalves". Applied Microbiology and Biotechnology. 94 (1): 1–10. doi:10.1007/s00253-011-3819-9. ISSN 0175-7598. PMC 3304057. PMID 22354364.
  5. ^ a b Seilacher, Adolf (1990-01-01). "Aberrations in bivalve evolution related to photo- and chemosymbiosis". Historical Biology. 3 (4): 289–311. Bibcode:1990HBio....3..289S. doi:10.1080/08912969009386528. ISSN 0891-2963.
  6. ^ a b König, Sten; Le Guyader, Hervé; Gros, Olivier (2015-02-01). "Thioautotrophic bacterial endosymbionts are degraded by enzymatic digestion during starvation: Case study of two lucinids Codakia orbicularis and C. orbiculata" (PDF). Microscopy Research and Technique. 78 (2): 173–179. doi:10.1002/jemt.22458. ISSN 1097-0029. PMID 25429862. S2CID 24772017.
  7. ^ Elisabeth, Nathalie H.; Gustave, Sylvie D.D.; Gros, Olivier (2012-08-01). "Cell proliferation and apoptosis in gill filaments of the lucinid Codakia orbiculata (Montagu, 1808) (Mollusca: Bivalvia) during bacterial decolonization and recolonization". Microscopy Research and Technique. 75 (8): 1136–1146. doi:10.1002/jemt.22041. ISSN 1097-0029. PMID 22438018. S2CID 7250847.
  8. ^ Bright, Monika; Bulgheresi, Silvia (2010-03-01). "A complex journey: transmission of microbial symbionts". Nature Reviews Microbiology. 8 (3): 218–230. doi:10.1038/nrmicro2262. ISSN 1740-1526. PMC 2967712. PMID 20157340.
  9. ^ a b Gros, Olivier; Elisabeth, Nathalie H.; Gustave, Sylvie D. D.; Caro, Audrey; Dubilier, Nicole (2012-06-01). "Plasticity of symbiont acquisition throughout the life cycle of the shallow-water tropical lucinid Codakia orbiculata (Mollusca: Bivalvia)". Environmental Microbiology. 14 (6): 1584–1595. Bibcode:2012EnvMi..14.1584G. doi:10.1111/j.1462-2920.2012.02748.x. ISSN 1462-2920. PMID 22672589.
  10. ^ Gourdine, Jean-Philippe; Smith-Ravin, Emilie Juliette (2007-05-01). "Analysis of a cDNA-derived sequence of a novel mannose-binding lectin, codakine, from the tropical clam Codakia orbicularis". Fish & Shellfish Immunology. 22 (5): 498–509. Bibcode:2007FSI....22..498G. doi:10.1016/j.fsi.2006.06.013. PMID 17169576.
  11. ^ Stanley, S. M. (2014). "Evolutionary radiation of shallow-water Lucinidae (Bivalvia with endosymbionts) as a result of the rise of seagrasses and mangroves". Geology. 42 (9): 803–806. Bibcode:2014Geo....42..803S. doi:10.1130/g35942.1.
  12. ^ a b Heide, Tjisse van der; Govers, Laura L.; Fouw, Jimmy de; Olff, Han; Geest, Matthijs van der; Katwijk, Marieke M. van; Piersma, Theunis; Koppel, Johan van de; Silliman, Brian R. (2012-06-15). "A Three-Stage Symbiosis Forms the Foundation of Seagrass Ecosystems". Science. 336 (6087): 1432–1434. Bibcode:2012Sci...336.1432V. doi:10.1126/science.1219973. hdl:11370/23625acb-7ec0-4480-98d7-fad737d7d4fe. ISSN 0036-8075. PMID 22700927. S2CID 27806510.
  13. ^ Petersen, Jillian M.; Kemper, Anna; Gruber-Vodicka, Harald; Cardini, Ulisse; Geest, Matthijs van der; Kleiner, Manuel; Bulgheresi, Silvia; Mußmann, Marc; Herbold, Craig (2016-10-24). "Chemosynthetic symbionts of marine invertebrate animals are capable of nitrogen fixation". Nature Microbiology. 2 (1): 16195. doi:10.1038/nmicrobiol.2016.195. ISSN 2058-5276. PMC 6872982. PMID 27775707.
  14. ^ König, Sten; Gros, Olivier; Heiden, Stefan E.; Hinzke, Tjorven; Thürmer, Andrea; Poehlein, Anja; Meyer, Susann; Vatin, Magalie; Mbéguié-A-Mbéguié, Didier (2016-10-24). "Nitrogen fixation in a chemoautotrophic lucinid symbiosis". Nature Microbiology. 2 (1): 16193. doi:10.1038/nmicrobiol.2016.193. ISSN 2058-5276. PMID 27775698.
  15. ^ "WoRMS - World Register of Marine Species - Lucinidae J. Fleming, 1828". www.marinespecies.org. Retrieved 2022-11-24.
  • Stewart, R. B. (1930). Gabb's California Cretaceous and Tertiary type lamellibranchs. Academy of Natural Sciences of Philadelphia, Special Publications. 3: 1-314, pls 1-17.
  • Taylor J. & Glover E. (2021). Biology, evolution and generic review of the chemosymbiotic bivalve family Lucinidae. London: The Ray Society [Publication 182]. 319 pp.
  • Powell A W B, New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1