Cave shrimp
| Cave shrimp | ||||||||||||
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Cave Shrimp ( Niphargus ictus ) |
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| Scientific name | ||||||||||||
| Niphargus | ||||||||||||
| Schiødte , 1847 |
The niphargus ( Niphargus ) form a genus of amphipods (amphipods), which in Europe in fresh water from caves or underground water is common. Niphargus is Cave Animal of the Year 2009.
features
The cave hives, like most cave animals, are blind. The large eyes that shape the appearance of the head of other amphipods have receded in this genus in the course of evolution. The crabs are colorless and appear transparent to white. They are up to 30 millimeters long.
The largest species belong to the troglobionts , the cave dwellers. In the case of the cave shrimp it can also be observed that the species living in caves are much larger than their close relatives in other habitats. These species have very long antenna 2. which make orientation easier.
Life in the gap system of the groundwater also results in an adjustment in size. These species are often less than 5 mm long, either with a slender and elongated body or with a stocky body and large contiguous or partially overlapping coxal plates. These adaptations are related to the locomotion of the amphipods in the inhabited biotopes.
distribution
The distribution area of the cave hives includes the Mediterranean areas of southern Europe , with the exception of the Iberian Peninsula , large parts of central and eastern Europe as far as the Ukraine and the Caucasus, and small areas in northern Europe . A particularly large number of species are known from the karst areas of Southeast Europe .
It was assumed that Niphargus could not survive in groundwater and cave systems of the areas of Europe covered by the Pleistocene ice sheets and only immigrated there later.
habitat
As well as in cave waters, cave shrimp also live in the water reservoirs of mines , in the gravel of river valleys, in wells and springs. The amphipods can also get into the pipes of the water supply companies via springs and groundwater. There are also permanent occurrences in the deep layers of the alpine lakes, but only around 5 percent of the Niphargus species live here .
The cave shrimp feed mostly predatory on the smaller inhabitants of the gap systems of the groundwater body and the caves like hoppers . But they can also live on detritus and graze on bacterial films.
The ecology and way of life of the cave shrimp have not yet been adequately researched. A symbiosis of Niphargus ictus with chemoautotrophic sulfur-oxidizing bacteria of the genus Thiothrix was recently discovered in the waters of the Frasassi cave system, which are rich in hydrogen sulfide . These bacteria cover the exoskeleton of the cave shrimp and are moved by them through the water. Other Thiothrix -Phylotypen the cave system live in slow-growing biofilms at the boundary layers of the waters. The function of bacteria within the symbiotic community is to detoxify the water and produce nutrients. Similar symbioses were previously only observed in marine habitats.
Saprobic index
The saprobic index for representatives of the genus Niphargus is 1.0.
Systematics
Since the genus was first described by Jørgen Matthias Christian Schiødte in 1847 , more and more species and subspecies of the cave shrimp have become known. The biologists at the University of Ljubljana in Slovenia list more than 300 species on a website specially set up to process the classification of these cave animals. The difficulty in creating a species list is to decide which morphological peculiarities from a plethora of variable characteristics are decisive for speciation. Due to the isolation of the animals in certain cave systems or groundwater bodies, the individual populations have diverged. Many sub-genera and subspecies have been described. Much of it is rare, restricted to a small area or cannot be collected regularly due to the inaccessibility of the caves. This also makes it difficult to revise the entire system through molecular biological and phylogenetic comparisons of the individual species.
Selected species
The selection of species includes those for which there is identification literature or images of systematically relevant characteristics.
Individual evidence
- ↑ Höhlentier 2009 ( Memento of the original from January 27, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Group Geomicrobiology and Biosignatures in the Deep Biosphere ( Memento of the original from December 1, 2010 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. at the Georg-August-Universität Göttingen
- ↑ Sharmishtha Dattagupta, Irene Schaperdoth, Alessandro Montanari, Sandro Mariani, Noriko Kita, John W. Valley and Jennifer L. Macalady: A novel symbiosis between chemoautotrophic bacteria and a freshwater cave amphipod . The ISME Journal advance online publication, Multidisciplinary Journal of Microbial Ecology, April 9, 2009 Abstract
- ↑ Meyer, Detlef .: Macroscopic biological field methods for assessing the water quality of rivers: with lists of species for beginning and experienced investigators and detailed descriptions and images of the indicator organisms . 4th, unchanged. BUND, Hannover 1990, ISBN 3-9800871-4-X .
- ^ List of species of the genus Niphargus from the University of Ljubljana
- ↑ Identification key for the species of the genus Niphargus ( Memento of the original from September 19, 2004 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Example: Niphargus balcanicus ; Photos in the Niphargus species list
Web links
- Niphargus website of the University of Ljubljana (accessed July 17, 2009)
- Niphargus working group (accessed July 18, 2009)
- Cave Animal of the Year 2009 (accessed July 18, 2009)
- The cave shrimp. In: Fauna Europaea Database. European Commission under the Fifth Framework Program, accessed on February 27, 2010 .
Cave shrimp (2009) | Ragged Owl (2010) | Great mouse-eared mouse (2011) | Great Cave Spider (2012) | Cave mushroom mosquito (2013) | Höhlenwasserassel (2014) | Cellar gloss snail (2015) | Cave Long Legs (2016) | Four-spotted cave parasitic wasp (2017) | Schwarzer Schnurfüßer (2018) | Common cave mosquito (2019) | Brick Wall (2020)