Delavalia palustris

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Delavalia palustris
Systematics
Subclass : Copepods (Copepoda)
Order : Harpacticoida
Family : Miraciidae
Subfamily : Stenheliinae
Genre : Delavalia
Type : Delavalia palustris
Scientific name
Delavalia palustris
Brady , 1869

Delavalia palustris ( synonym Stenhelia palustris ) is a species of copepods from the order Harpacticoida . The species is mainly found in the North Atlantic .

features

The species is very small and becomes a maximum of 0.6 millimeters long. The greatest width at the end of the first segment of the cephalothorax is 0.2 millimeters. The color is whitish and may appear yellowish on top. The cephalothorax consists of five segments. The abdomen is made up of six segments, the fourth of which is the shortest. An essential characteristic of Delavalia palustris is considered to be that the inner branch ( endopodite ) of the first swimming leg is only two-part. The first pair of swimming legs is the same for both sexes, the second is built differently. The latter is tripartite on both branches.

distribution

Delavalia palustris lives as a resident of the marine Benthals mainly on the coasts of the North Atlantic . The range of this copepod extends in the north to the White Sea . In the first description by George Stewardson Brady in 1869, the coasts of the British Isles are given as habitat, Georg Ossian Sars also proves their occurrence on the coasts of Norway . Shortly after Brady's publications, specimens from the Jade Bay near Wilhelmshaven were examined and identified by Albrecht Poppe as Delavalia palustris .

Way of life

Delavalia palustris who settled littoral (intertidal) of the coasts and the estuaries of rivers, such as the Scheldt in the Netherlands or the River Thames in England and is also in the salt marshes to find. Like many other representatives of the Harpacticoida, the cancer lives in this habitat as part of the meiofauna in the mud and in the sand gap system . In contrast to most other ground-dwelling copepods, Delavalia palustris actively builds living tubes that are lined with a mucous secretion. Like the other harpacticoiden copepods feeds Delavalia palustris of unicellular algae , cyanobacteria , flagellates , ciliates , fungi and heterotrophic bacteria . As a special feature, it was found that Delavalia palustris can synthesize polyunsaturated fatty acids from bacteria . Other copepods are dependent on phytoplankton or phytobenthos for food in order to obtain these unsaturated fatty acids for their metabolism.

Systematics and taxonomy

After a long period of stability, the copepods' system has started to move in the 21st century. Phylogenetic methods make great demands on the description of newly discovered species. In the course of this, many changes were made in the area of ​​the Harpacticoida, but these have not yet been based on molecular genetic studies.

External system

Delavalia palustris belongs to the subfamily Stenheliinae within the family Miraciidae . The subfamily was counted to the Diosaccidae family for a long time before it was united with the Miraciidae family. The Diosaccidae got their name from Georg Ossian Sars in 1906 because of the two ice sacs that attach to the genital segment of the female. The name Miraciidae had already been introduced by Dana in 1846 and was therefore given priority when the two groups were merged according to the priority rule.

Delavalia palustris is the type species of the genus Delavalia . GO Sars merged the genus Delavalia with Stenhelia in 1906 . A. Monard rebuilt Delavalia as a subgenus of Stenhelia . In 2002 the subgenus Delavalia and Stenhelia were separated from each other and Delavalia was re-established as a genus. However, the new genus is not viewed as monophyletic either .

Subspecies

There are currently two subspecies of Delavalia palustris . However, they are likely to be separate species. The large range of the species suggests that it could be a species complex that cannot be broken down by external characteristics .

  • Delavalia palustris bispinosa Bodin, 1970
  • Delavalia palustris palustris Brady, 1868

Individual evidence

  1. ↑ a b Fang-Hong Mu & Rony Huys: New species of Stenhelia (Copepoda, Harpacticoida, Diosaccidae) from the Bohai Sea (China) with notes on subgeneric division and phylogenetic relationships. Cahiers de Biologie Marine 43, 1, pp. 179-206, 2002
  2. ↑ a b Albrecht Poppe : The free-living copepods of the Jadebusen. I. Treatises published by the Natural Science Association in Bremen, 9, pp. 167–206, 1885, p. 198
  3. ↑ PN Kornev & EC Chertoprud: Copepod Crustaceans of the Order Harpacticoida of the White Sea: Morphology, Systematics, Ecology. Biology Faculty, Moscow State University, Tovarishchestvo Nauchnikh Izdanii KMK, Moscow 2008
  4. ↑ George Stewardson Brady: On the crustacean fauna of the salt-marshes of Northumberland and Durham. Natural History Transactions of Northumberland, Durham and Newcastle-upon-Tyne, 3, pp. 120-136, 1869
  5. ^ A b Georg Ossian Sars: An Account of the Crustacea of ​​Norway. Copepoda Harpacticoida. Parts XV & XVI. Diosaccidae (concluded), Canthocamptidae (part). Bergen Museum, Bergen 1906
  6. ↑ a b Clio Cnudde: Trophic ecology of intertidal harpacticoid copepods, with emphasis on their interactions with bacteria. Dissertation at Ghent University , 2013 ( abstract )
  7. ↑ Martin J. Attrill (Ed.): A Rehabilitated Estuarine Ecosystem: The environment and ecology of the Thames Estuary. Kluwer Academic Publishers, 1998 ISBN 0-412-49680-1
  8. ^ GT Chandler & JW Fleeger: Tube-building by a marine meiobenthic harpacticoid copepod. Marine Biology, 82, pp. 15-19, 1984
  9. ↑ Elke Willen: Notes on the systematic position of the Stenheliinae (Copepoda, Harpacticoida) within the Thalestridimorpha and description of two new species from Motupore Island, Papua New Guinea. Cahiers de Biologie Marine 43, 1, pp. 27-42, 2002
  10. ^ A. Monard: Les Harpacticoides marins de Banyuls. Archives de Zoologie Expérimentale et Générale, 67/4, pp. 259–443, 1928
  11. ↑ Tomislav Karanovic & Kichoon Kim: New insights into polyphyly of the harpacticoid genus Delavalia (Crustacea, Copepoda) through morphological and molecular study of an unprecedented diversity of sympatric species in a small South Korean bay. Zootaxa, 3783, 1, pp. 1-096

literature

  • Elke Willen: Phylogeny of the Thalestridimorpha Lang, 1944 (Crustacea, Copepoda). Cuvillier Verlag, Göttingen 2000 ISBN 3-89712-847-0
  • George Stewardson Brady: On the crustacean fauna of the salt-marshes of Northumberland and Durham. Natural History Transactions of Northumberland, Durham and Newcastle-upon-Tyne, 3, pp. 120-136, Newcastle-upon-Tyne 1869 (first description)
  • Georg Ossian Sars: An Account of the Crustacea of ​​Norway. Copepoda Harpacticoida. Parts XV & XVI. Diosaccidae (concluded), Canthocamptidae (part). Bergen Museum, Bergen 1906

Web links

  • G. Boxshall, T. Chad Walter: Delavalia palustris Brady, 1868. In: TC Walter & G. Boxshall: World of Copepods database , 2013, World Register of Marine Species , accessed March 25, 2014