Notobranchaeidae

While they are not particularly strong swimmers, the foot of these organisms is modified into wing-like structures, called parapodia that they employ for locomotion.[5] Additionally, like other Pteropods of the order Gymnosomata,[6] Notobrachaeidae lack shells entirely as adults.[7][8] However, they do possess a shell earlier on in their lives.[8] They are also defined by how they possess a posterior gill, strong jaws, grasping tentacles that frequently possess suckers resembling those of cephalopods, and usually buccal cones as well.[9]

Like other members of the clade Gymnosomata, Notobrachaeidae are highly specialized holoplanktonic carnivores.[10] In other words, they spend their entire lives hunting in the water column and cannot swim against the column.[10] Also like other members of this clade, Notobrachaeidae feed are very specific prey, with a species in this clade usually specializing in hunting one specific genus of thecosomes, which are also known as "sea butterflies," and form a sister clade to Gymnosomata with the primary difference being how adults of that clade possess shells into adulthood while Gymnosomata do not.[8][10]

Members of this family are found globally throughout the upper reaches of the water column, in the pelagic zone, most commonly the epipelagic zone.[8] Following the trend of Pteropods in general, they tend to have the highest species diversity tropical and subtropical latitudes but are less abundant under these conditions.[8] Conversely, they are more abundant but possess less variety in terms of species closer to the north and south poles.[8] However, even in the tropics, they generally appear in high concentrations, resulting in their frequently playing important roles in planktonic food webs.[4][5][11]

Genera and species in the family Notobranchaeidae include:

Genus: Notobranchaea Pelseneer, 1886

• Notobranchaea bleekerae van der Spoel & Pafort-van Iersel, 1985
  • Distribution : Oceanic
• Notobranchaea grandis Pruvot-Fol, 1942
  • Distribution : Oceanic
  • Length : 15 mm
• Notobranchaea hjorti (Bonnevie, 1913)
• Notobranchaea inopinata Pelseneer, 1887
  • Distribution : Oceanic
  • Length : 5 mm
• Notobranchaea longicollis (Bonnevie, 1913)
• Notobranchaea macdonaldi Pelseneer, 1886
  • Distribution : Bermuda, Oceanic
  • Length : 5 mm
• Notobranchaea tetrabranchiata Bonnevie, 1913
  • Distribution : Oceanic
  • Length : 16 mm
• Notobranchaea valdiviae Meisenheimer, 1905

Genera brought into synonymy

• Microdonta Bonnevie, 1913: synonym of Notobranchaea Pelseneer, 1886 (invalid: junior homonym of Microdonta Dejean, 1835 [Coleoptera]; Schleschia is a replacement name)
• Prionoglossa Tesch, 1950: synonym of Notobranchaea Pelseneer, 1886
• Schleschia Strand, 1932: synonym of Notobranchaea Pelseneer, 1886

• Bouchet, P., Rocroi, J.-P. (2005). Classification and nomenclature of gastropod families. Malacologia. 47(1-2): 1-397 ISBN 3-925919-72-4.
• MolluscaBase (2019). MolluscaBase. Notobranchaeidae Pelseneer, 1886. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=23080 on 2019-04-16
• Gofas, S.; Le Renard, J.; Bouchet, P. (2001). Mollusca. in: Costello, M. J. et al. (eds), European Register of Marine Species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Patrimoines Naturels. 50: 180-213

• "Prionoglossa". Integrated Taxonomic Information System.
• Bonnevie K. (1913) Pteropoda from the "Michael Sars" North Atlantic Deep-Sea Expedition 1910. Report on the Scientific Results of the "Michael Sars" North Atlantic Deep Sea Expedition 1910 3(1) 1-85, pls. 1-9.