Limacina helicina antarctica is a traditionally recognized subspecies of the shelled pteropod mollusk Limacina helicina, a key organism in polar pelagic ecosystems, where it can can account for 50% of total zooplankton abundance (number of individuals per unit volume). Pteropods are strictly pelagic mollusks that are highly adapted to life in the open ocean. They are commonly referred to as ‘‘sea butterflies’’ due to their wing-like parapodia, which are evolutionary modifications of the gastropod foot. Pteropods produce large mucus webs to filter-feed on phytoplankton as well as small zooplankton (including their own juveniles). Species of the Order Thecosomata, including L. helicina (the only thecosome pteropod in Arctic waters), produce a fragile external calcium carbonate (aragonite) shell. Shelled pteropods play a significant geochemical role in the oceans, as they contribute to the export of calcium carbonate and can represent a major component of the carbon transport to the deep ocean. The likely effects of ocean acidification (resulting from the absorption of increasing quantities of CO2 from the atmosphere) have been studied in a variety of shell-building marine organisms, including L. helicina, which may be especially vulnerable as a result of its aragonite shell and its distribution in polar oceans, which acidify especially quickly due to their particular chemical and physical characteristics. (Comeau et al. 2010 and references therein; Hunt et al. 2010)
Although L. helicina was formerly believed to have a bipolar distribution, further investigation has shown that the Arctic and Antarctic forms are genetically distinct species. Traditionally, northern and southern hemisphere forms were recognized as subspecies and referred to as L. h. helicina and L. h. antarctica, respectively. Three morphotypes, or "forma", of the subspecies L. h. helicina have often been recognized (acuta, helicina, and pacifica) along with two morphotypes of L. h. antarctica (antarctica and rangi). However, genetic studies have revealed that L. h. helicina and L. h. antarctica differ by around 34% in mitochondrial COI sequence, far more divergence than would be seen intraspecifically. Sequence data are not yet available to help clarify the taxonomic status of the various morphotypes, which may or may not actually be genetically distinct. (Hunt et al. 2010)
Molecular Biology and Genetics
Barcode data: Limacina helicina antarctica
There are 2 barcode sequences available from BOLD and GenBank. Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species. See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Limacina helicina antarctica
Public Records: 1
Specimens with Barcodes: 3
Species With Barcodes: 1
Until 2010 this taxon was known only as Limacina helicina antarctica or as Limacina helicina f. antarctica. Limacina antarctica is however now considered to be a separate species from Limacina helicina, based on cytochrome c oxidase subunit I (COI) gene sequences.
Limacina antarctica has a sinistral and very thin shell. Its thickness is approximately 2–9 μm. There are ribs on the surface of the shell. There are differences in the shell structure between Limacina antarctica and Limacina helicina.
The width of the shell is 0.5-6 mm.
Limacina antarctica is a holoplanktonic species. It is very abundant in the Southern Ocean, with up to 2681 individuals per m3. This species is abundant in the Ross Sea, Antarctica. It is sometimes even more abundant than krill.
This snail is a primary consumer and directly depends on phytoplankton. When the phytoplankton is reduced, the population of Limacina antarctica is also reduced, and it can even disappear as happened in McMurdo Sound in the summer of 2000-2001. It is considered an indicator species of the health of the ecosystem. Under different conditions in McMurdo Sound there can be over 300 individuals per m3, which is over 20% of the biomass of zooplankton.
Fecal pellets of Limacina antarctica and its quantity have been firstly described by Manno et al. (2010). Fecal pellets are oval, greenish brown and with peritrophic membrane. A size of a single pellet varies from 103 μm (286600 μm3) to 120 μm (440,610 μm3). A single Limacina antarctica produces about 6-11 pellets daily. Population of Limacina antarctica in the studied area in the Ross Sea produced from about 71,000 pellets per square meter per year to about 362,000 pellets per square meter per year. Fecal pellets of Limacina antarctica has contributed to about 19% of flux of organic carbon. Fecal pellets of Limacina antarctica together with dead Limacina antarctica can cover up to 72% (estimation) of organic carbon flux to the deep water.
- The gastropod Clione antarctica feeds only on Limacina antarctica. There is a coevolutionary relationship between this specilized predator and its prey; their life cycles are parallel.
- The medusae Solmundella bitentaculata and Diplulmaris antarctica
- Fish in the family Myctophidae heavily depend on Limacina antarctica. Limacina sp. is a food species for a number of myctophid fishes in the Southern Ocean: Electrona antarctica, Electrona paucirastra, Electrona subaspera, Metelectrona herwigi, Protomyctophum normani, Diaphus taaningi, Diaphus hudsoni, Gymnoscopelus nicholsi, Ceratoscopelus warmingii and Symbolophorus boops.
- Also notothenioid fish (family Nototheniidae) heavily depend on Limacina antarctica as food. For example fishes: Trematomus newnesi, Trematomus bernacchii, Trematomus hansoni, Trematomus centronotus and Pagothenia borchgrevink.
- Whales heavily depend on this species
- Woodward S. P. (1854). A manual of the Mollusca; or, A rudimentary treatise of recent and fossil shells. 2: 207. London. Plate 14, figure 41.
- WoRMS (2010). Limacina antarctica Woodward, 1854. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=509607 on 2011-01-29
- Sato-Okoshi, W.; Okoshi, K.; Sasaki, H.; Akiha, F. (2010). "Shell structure of two polar pelagic molluscs, Arctic Limacina helicina and Antarctic Limacina helicina antarctica forma antarctica". Polar Biology 33 (11): 1577. DOI:10.1007/s00300-010-0849-1.
- Hunt, B.; Strugnell, J.; Bednarsek, N.; Linse, K.; Nelson, R. J.; Pakhomov, E.; Seibel, B.; Steinke, D. et al. (2010). Finkel, Zoe. ed. "Poles Apart: The "Bipolar" Pteropod Species Limacina helicina is Genetically Distinct Between the Arctic and Antarctic Oceans". PLoS ONE 5 (3): e9835. DOI:10.1371/journal.pone.0009835. PMC 2847597. PMID 20360985. //www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2847597.
- "Limacina helicina antarctica antarctica". Marine Species Identification Portal, accessed 9 February 2011.
- Linse, K.; Brandt, A.; Hilbig, B.; Wegener, G. (2004). "Composition and distribution of suprabenthic fauna in the south-eastern Weddell Sea and off King George Island". Antarctic Science 14. DOI:10.1017/S0954102002000512.
- Accornero, A.; Manno, C.; Esposito, F.; Gambi, M. C. (2003). "The vertical flux of particulate matter in the polynya of Terra Nova Bay. Part II. Biological components". Antarctic Science 15 (2): 175. DOI:10.1017/S0954102003001214. PDF.
- Ward, P. (2004). "The distribution of zooplankton in an Antarctic fjord at South Georgia during summer and winter". Antarctic Science 1 (2). DOI:10.1017/S0954102089000210.
- Comeau, S.; Gorsky, G.; Jeffree, R.; Teyssié, J. -L.; Gattuso, J. -P. (2009). "Impact of ocean acidification on a key Arctic pelagic mollusc (Limacina helicina)". Biogeosciences 6: 1877. DOI:10.5194/bg-6-1877-2009.
- Seibel, B. A.; Dierssen, H. M. (2003). "Cascading trophic impacts of reduced biomass in the Ross Sea, Antarctica: Just the tip of the iceberg?". The Biological bulletin 205 (2): 93–97. PMID 14583506.
- Orr, J. C.; Fabry, V. J.; Aumont, O.; Bopp, L.; Doney, S. C.; Feely, R. A.; Gnanadesikan, A.; Gruber, N. et al. (2005). "Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms". Nature 437 (7059): 681–686. DOI:10.1038/nature04095. PMID 16193043. PDF. (author's draft).
- Manno, C.; Tirelli, V.; Accornero, A.; Fonda Umani, S. (2009). "Importance of the contribution of Limacina helicina faecal pellets to the carbon pump in Terra Nova Bay (Antarctica)". Journal of Plankton Research 32 (2): 145. DOI:10.1093/plankt/fbp108.
- k., W.; d., K.; j., H. (2001). "Mycosporine-like amino acids (MAAs) in phytoplankton, a herbivorous pteropod ( Limacina helicina ), and its pteropod predator ( Clione antarctica ) in McMurdo Bay, Antarctica". Marine Biology 139 (5): 1013. DOI:10.1007/s002270100654.
- Larson, R. J.; Harbison, G. R. (1990). "Medusae from Mcmurdo Sound, Ross Sea including the descriptions of two new species, Leuckartiara brownei and Benthocodon hyalinus". Polar Biology 11. DOI:10.1007/BF00236517.
- Pakhomov E. A., Perissinotto R. & McQuaid C. D. (1996). "Prey composition and daily rations of myctophid fishes in the Southern Ocean". Marine Ecology Progress Series 134: 1-14. PDF.
- Mesa, M. L.; Vacchi, M.; Zunini Sertorio, T. (2000). "Feeding plasticity of Trematomus newnesi (Pisces, Nototheniidae) in Terra Nova Bay, Ross Sea, in relation to environmental conditions". Polar Biology 23: 38. DOI:10.1007/s003000050006.
- Foster, B. A.; Montgomery, J. C. (1993). "Planktivory in benthic nototheniid fish in McMurdo Sound, Antarctica". Environmental Biology of Fishes 36 (3): 313. DOI:10.1007/BF00001727.