Striped dwarf crayfish

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Striped dwarf crayfish
Cambarellus patzcuarensis (in the aquarium)

Cambarellus patzcuarensis (in the aquarium)

Systematics
Partial order : Large crayfish (Astacidea)
Superfamily : Crayfish (Astacoidea)
Family : Cambaridae
Subfamily : Cambarellidae
Genre : Dwarf crayfish ( Cambarellus )
Type : Striped dwarf crayfish
Scientific name
Cambarellus patzcuarensis
Villalobos , 1943

The striped pygmy crayfish or Pátzcuaro crayfish ( Cambarellus patzcuarensis ) is an autochthonous crayfish of the genus pygmy crayfish ( Cambarellus ) native to Mexico . In its wild form, it is considered an endangered species. The Cambarellus patzcuarensis was long considered a subspecies of the Cambarellus montezumae . The “Aquarium Atlas” by the aquaristic experts Hans A. Baensch and Hans-Georg Evers from 2002 states that the German first introduction was “unknown, probably not until 2000 or even 2001”.

Its orange color variant, the orange pygmy crayfish , also Cambarellus patzcuarensis sp. orange , CPO for short , is very popular in the aquarium hobby and is often offered in pet shops. However, this is a cultivated form that cannot be observed in nature.

features

The cancer is both diurnal and nocturnal. According to Baensch and Evers, the fully grown females reach a full length of up to 3.50 centimeters and are slightly wider when viewed from the rear than the slightly smaller males, which measure around three centimeters. The claws of adult males are slightly narrower and up to 20 percent longer than those of females. As with most Cambarellus species, their shorter claws are thicker than those of the male animals. Overall, the physique of most males appears to be considerably slimmer, while the females appear to be more robust and significantly larger. The ichthyologist Ulrich Schliewen , section head of the Zoological State Collection in Munich , stated the maximum length of four centimeters in 2011. In older publications he also mentioned lengths of five centimeters. According to the invertebrate experts and non-fiction authors Reinhard Pekny and Chris Lukhaup, this size is actually possible for females in the aquarium with good care . The age information for the CPOs is usually given as around 18 months. Pekny and Lukhaup found that the females usually get older than the males. Under good conditions, a maximum life expectancy of two years is possible, while the males die after around one and a half years.

Like all species of the Cambaridae family, the sexes of this dwarf crayfish can be easily differentiated by the mating pens ( gonopods ) that can be seen on the underside of the body of the males , which can also be seen with the naked eye. In the wild, the striped dwarf crayfish often shows dark vertical stripes on the dark to light brown upper side. More rarely, specimens also have small dark or light spots. The intensity of the striations varies. Shortly after molting, it is darker and stronger than if it was a long time ago. Cambarellus patzcuarensis is similar in color to related species such as the Montezuma crayfish ( Cambarellus montezumae) and the Louisiana crayfish ( Cambarellus shufeldtii ).

Color variations

In the orange cultivated form, the crab became the international ambassador of Lago de Pátzcuaro

The color variant "Orange" ranges from light orange to bright orange and shows a slight marbling on the shell. The eponymous stripes of the pygmy crayfish sometimes appear in this color form. You cannot find this orange color variant in nature. This coloration would be an all too conspicuous signal for the crab's predators, although most animals, with the exception of birds, cannot perceive intense red and orange tones as a color. In the water there is a higher absorption of the red and orange components of the light spectrum , but this has hardly any effect on the visibility of the crabs, as their habitat is mostly in shallow water. Birds could therefore easily spot them by their coloring. In its natural environment, the original gray-brown base tone, which is sometimes provided with washed-out stripes or dots, is an ideal camouflage color. The appearance of the orange color variant was therefore observed for the first time in the aquarium. Since then this color form of the striped dwarf crayfish has been very well known in the aquarium hobby.

Another breed of color is the black or brown variant, which is commercially available under the names C. patzacuensis sp. black or C. patzacuensis sp. chocolate finds.

Distribution and ecology

A Cambarellus patzcuarensis in its natural form

The nominate form of the striped dwarf crayfish is endemic to the Lago de Pátzcuaro , a lake in the Mexican state of Michoacán . Experts assume that the species could still be found in streams and ponds in the vicinity. So far sources have been located in the villages of Tzurumútaro , Opopeo and Chapultepec . The populations discovered there usually exist in isolation. Due to the massive increase in the human population, the resulting damage to nature by civilization, together with increasing industrialization in all areas of life, the lake is now a heavily damaged habitat for the flora and fauna that live there.

There is speculation about the origin of Cambarellus patzcuarensis in Lago de Pátzcuaro. Studies suggest that there may have been a runoff from Lake Pátzcuaro into the Río Lerma system 38,000 to 25,000 years ago . During this time high lacustric deposits formed on the lake . Before and after the subsequent glacial period 25,000 to 13,000 years ago, cool freshwater conditions can be detected at Lago de Pátzcuaro. The lake must have been deeper then than it is today. Diatom species have been identified between 30,000 and 10,000 years ago that bloom in winter and spring. Before the Holocene, the pollen and plant spectrum documented cooler climatic conditions with a seasonally significantly higher humidity. About 10,000 years ago the lake became shallower and eutrophic . Today's climate developed. During the Middle Holocene 6,000 to 3,000 years ago, the lake water was now alkaline enough to deposit marl rich in ostracods.

The cancer colonizes the benthic , durchkrauteten and marshy edge areas of the lake that are largely covered with mud. The lake's flora comprises 48 species in 22 plant families and is therefore particularly rich in species compared to other Mexican water systems. The aquatic vegetation, which forms an important part of the natural habitat of this crab, includes, among many others, the small fat leaf ( Bacopa monnieri ), the narrow-leaved Merk ( Berula erecta ), the rough horn leaf ( Ceratophyllum demersum ), the marsh herb Cyperus niger , the giants -Nadelsimse ( Eleocharis montevidensis ), the Hahnenfußähnliche pennywort ( Hydrocotyle ranunculoides ), the South American frog bite ( Limnobium laevigatum ), the Lemna gibba ( Lemna gibba ) the Guadeloupe Nixkraut ( Najas guadalupensis ), the Mexican water lily ( Nymphaea mexicana ), which the Illinois pondweed ( Potamogeton illinoensis ), the pondweed ( Potamogeton pectinatus ), the Buttercup Ranunculus dichotomus , the variable arrowhead ( Sagittaria latifolia ), the Broad arrowhead ( Sagittaria platyphylla ), the Totora ( Scirpus californicus ), the salt-Teichbinse ( Scirpus validus ), the multi- rooted pond lens ( Spirodela polyrrhiz a ), the southern cattail (Typha domingensis) , the broad-leaved cattail ( Typha latifolia ), the bladder herb Utricularia macrorhiza , the duckweed family Wolffia brasiliensis and Wolffiella lingulata , the water hyacinths Eichhornia crassipes and the Mexican bald cypress Taxodium mucronatum .

Limnology and Climate

The species-rich Pátzcuaro Lake was created in a former volcanic crater and is over 2000 meters above sea level. It has an area of ​​around 9,000 hectares with an average water depth of 4.70 meters. At its deepest point, just 12 meters were measured. Due to its shallow depth, the lake has extensive wetlands at the edges , which are particularly concentrated in the shallow water zones.

The mean water temperature fluctuated between 1922 and 1979 between 15.80 and 16.70 ° C. In a study from 2014, low values ​​of 14.80 ° C (pH value: 7.20) and high values ​​of 26.80 ° C (pH value: 8.80) were measured in 2011. The mean value this year was 17.97 ° C (pH value: 8.48) in February, 22.77 ° C (pH value: 8.81) in May, and 21.18 ° C in July (pH value: 9.58) and in September at 18 ° C (pH value: 9.02). The oxygen content sank continuously from February to September from 6.39 to 4.40 mg / l. The increase in algae from July onwards was clearly noticeable. With the oxygen content, the salt content also fell in the same period from an average of 0.46 ‰ in February to 0.09 ‰ in September and the associated conductivity (February: 948.58 nS / cm; September: 130.40 nS / cm). The pH value in the lake moved from February to September in the range of 8.48 to 9.02 in 2011 and was therefore in the alkaline range . Similar pH measurement results had already been achieved between 2006 and 2007 with 7.56 to 9.91. When caring for the crab in aquariums, the water should also be more alkaline. The water hardness of the lake fluctuates strongly between 12.5 ° dGH and 18 ° dGH. A higher proportion of lime, as occurs in hard water, also plays a major role in the formation of the crustacean. The lake is mainly fed by precipitation and groundwater flows. The climate is subhumid , i.e. five to six humid months with a precipitation rate of 922 to 1060 millimeters measured between 1922 and 1979; the total evaporation rate between 1939 and 1985 was 1351 to 1810 millimeters. Average outside temperatures of 12 to 18 ° C are typical in the area of ​​influence of the lake.

The phosphate content in the lake is usually no more than 1 ppm, unless it has been contaminated by phosphorus fertilizers.

Habitat destruction

In a study from 2009, the sustainable and accelerated destruction of the ecological system at the Lago de Pátzcuaro was explained. One of the main evils lay in the failure of decades of government policy, with the authors emphasizing the fishery management that has been promoted so far, which has led to the domestic fish stocks being greatly reduced and, in some cases, being brought to the brink of extinction. In addition to this misguided concept, which promoted the introduction of various exotic species through fish plantations into the endorheic lake basin, there are countless wastewater discharges from urban and rural areas as well as from agrochemicals . All these causes have led to a negative change in all previously known parameters in the lake.

Cambarellus patzcuarensis as a basibiont

In the natural surroundings of Lago de Pátzcuaro, a series of scientific studies published in 2001 identified a total of eight types of epistylis as epibionts in different distributions on the exoskeletons of Cambarellus patzcuarensis. These were: Epistylis bimarginata , Epistylis branchiophila , Epistylis carinogammari , Epistylis gammari , Epistylis gammari , Epistylis niagarae , Epistylis stammeri and Epistylis variabilis . In addition to the ciliates mentioned , other ciliophora from the group of sucking infusories benefit from the presence of the cancer in the lake. These are Podophrya sandy , Acineta tuberosa, and Tokophrya quadripartita . As the host of these life forms, cancer shows its great importance in the aquatic ecosystem of the lake and the need to keep it pure.

Reproduction

A female with eggs

To ensure the persistence of their species under adverse conditions, the crabs have developed their own reproductive strategies. The cyclical dimorphism between two clearly separable life phases in the males and a shortened larval development in the females are most likely the most important key point for the success of the animals in colonizing the lake. The life of the Cambaridae is characterized by this dimorphism of the males and is linked by the seasonal reproductive cycle. The transition from the first, sexually inactive juvenal life form to the second adult form takes place approximately during the middle phase of life of the male crayfish during the half-yearly molt. From then on, the males appear as sexually potent partners. Their now more aggressive behavior becomes evident through their growth, the hardening and coloration of the first pleopods and the presence of the thorn-shaped ischium hooks on the third and fourth pereiopods , with which the females are held during mating . The fertilization does not have to happen immediately. The female can store the sperm for up to six months in the sperm store (annulus ventralis) , which has the shape of the upside-down letter "U". The eggs are fertilized in the female's body and expelled through a pair of fallopian tubes. There they are attached to the pleopods by the female. The female is solely responsible for the offspring. With a constant movement of the pleopods, it creates a jet of water that helps aerate the developing eggs and clears away the dead eggs. The brood is protected by the females by bending their tail fan down and folding it forward.

As a rule, the incubation time of the eggs in Cambarellus patzcuarensis is around 25 days, or two or three weeks. Constant temperature conditions between 20 and 25 ° C are decisive for this period of time. As the water temperature decreases, embryonic development slows down. In general, larger females carry more eggs, but that too depends on the time of year. Egg loss can have various causes, including lack of fertilization or restraint, abrasion on the ground, predation, strong currents, lack of food or an oversupply of female crabs. Around 55 days after mating, embryos have developed in the eggs, which hatch as larvae around 75 days after mating. Cambarellus patzcuarensis first moults around 87 days after mating. A total of ten successive moults could be observed within 208 days. The success of the Cambarellus patzcuarensis even under less favorable conditions is due to the fact that the females are capable of two to three successive spawns.

A direct dependency of reproduction and water temperature has been scientifically proven. Experiments with 18 ± 1 ° C, 22 ± 1 ° C and 26 ± 1 ° C showed that the life, population and spawning of Cambarellus patzcuarensis sometimes showed statistical differences with regard to temperature fluctuations. Variations in survival, viability and number of eggs in pregnant females have been demonstrated. The analyzes showed that the females spawned more often at 18 ° C and 22 ° C. The lowest number of eggs was counted at 26 ° C, the highest at 18 ° C, with most of the juveniles surviving in the eggs at 26 ° C. Both sexes also achieved the highest survival rate at 18 ° C. No difference was found during the growth phases of the animals at the different temperatures.

The results of the study published in 2014 allow the following conclusions with regard to the reproductive capacity of Cambarellus patzcuarensis. The checked temperature fluctuations only have an impact on the females. Depending on the situation in which these female crabs find themselves, different temperature parameters are important. At 18 ° C, the lifespan of adult females and the number of eggs improve significantly, but these eggs need temperatures of 26 ° C for better development, which also has a positive effect on their ability to develop.

Keeping in the aquarium

The German Animal Welfare Act (TierSchG) requires that all animals to be cared for must be fed, cared for and housed appropriately according to their species and needs. No one should inflict pain, suffering, or harm on an animal for no good reason. In addition, keepers must have the knowledge and skills required for adequate nutrition, care and behavioral accommodation of the animal. In a similar way, the Animal Welfare Act in Austria stipulates that no animal may be inflicted unjustifiably pain, suffering or harm, or that it may be terrified. There animals are to be kept in such a way that their bodily functions and behavior are not disturbed and their adaptability is not overwhelmed. In Switzerland, in addition to similar aspects, dignity, the intrinsic worth of the animal, comes into play. In all countries, however, the status of invertebrates, in this case crabs, remains problematic, as the legislators have still not ascribed any or only a reduced sense of pain to this class of animals, although aquarium experts and scientists have long since provided evidence that crabs are capable of suffering.

Before purchasing an aquarium, sufficient information on keeping it must be available, because the maintenance of the CPO also has its special difficulties. For a large part of the aquatic animals kept by humans, the smaller an aquarium is planned, the more complicated it is to keep them, since a stable balance of the complex biological-ecological structures and functions of the abiotic and biotic processes is more difficult to achieve. In community aquariums in particular, it quickly becomes clear how fragile and unstable an otherwise intact habitat can become in the event of human failure. Here beginners' mistakes can be avoided with appropriately acquired information.

The striped dwarf crayfish, which according to Baensch and Evers (2002) can be kept in species tanks from 50 liters, according to the ichthyologists Jakob Geck and Ulrich Schliewen (2008) from at least 25 liters, is an individualist and has different preferences depending on the animal. Schliewen recommends keeping a pair or a trio in small artificial tanks, for larger tanks he can imagine a small group and in 2016 stated five individuals for a 30-liter tank. Schliewen recommends six to ten animals for a 60 liter tank. In 2008, however, Pekny and Lukhaup already saw species aquariums from a size of 12 liters for three to four CPOs as feasible. Such small tanks should never be used to keep multiple species. In addition to the complex interactions between biological conditions, which are difficult to foresee, animal welfare should also be in the foreground, as an aquarium and its inhabitants should never be regarded as "beautiful furniture" or belong in children's hands as "toys" without constant supervision. Even with a small tank, no animal lover can avoid constant intensive preoccupation with the topic, because even small aquariums do at least as much work in the weekly sum as a cat or a dog. Geck and Schliewen (2017) emphasized keeping the crab in pairs and not filtering too much in order to get some sludge and plant residues as a food supplement.

The CPOs are very tolerant of the water values; According to Geck and Schliewen (2008), the temperature should be a minimum of 16 and a maximum of 26 degrees Celsius. Schliewen restricted this information in 2009, "because the animals do not tolerate more than 25 ° C" and repeated this requirement together with Geck in 2017. Pekny and Lukhaup (2008) also give values ​​of 15 to 25 degrees here. With this information, they refer to the water temperatures in Lago de Pátzcuaro and add that higher temperatures were also measured in the shallow bank regions when exposed to sunlight.

Some breeders use a heating rod in order to keep a constant 25 degrees, the willingness of the animals to reproduce is greater, but the lifespan is also shorter. Due to the natural range of fluctuation that is given in Lake Pátzcuaro, a heating element can be dispensed with at normal room temperatures in a species pool. In summer temperatures - depending on the location of the pool - cooling by commercially available fans is more important. These also bring slight surface movements into the water, which can contribute to the relining of the oxygen content, which drops in warm temperatures.

It is important that the pool of the CPOs is well structured, offers hiding places and has good or dense planting. In contrast to many other types of cancer, aquatic plants are hardly touched by the CPOs. Nothing stands in the way of beautiful planting of the aquarium. Opportunities for climbing walls or plants and ample hiding places for the time of the molt are also important, since the animals have little to do with their fellow crabs in their time as butter crabs and can fall victim to cannibalism. Some specimens love to sit on floating plants and take in oxygen from the air, even if the aquarium has well-saturated oxygen levels. A good ventilation of the pool is particularly important, whereby the inexpensive and currentless Hamburg mat filter has proven itself very well. When planning, it should be remembered that the filter does not become a death trap, especially for larvae and young animals. Many commercially available filters are not or only to a limited extent suitable for crab tanks.

Cancers prefer a cluttered aquarium rather than one that is too clean. Sufficient loose sediments , such as the sludge consisting of various decay substances and bacteria , should therefore not be avoided. A good crab aquarium also includes untreated bog wood, sea almond leaves with their germ-inhibiting substances and alder cones or the like, which release their valuable humic substances into the water. Sea almond leaves and cones should be changed in relatively short periods of time. In view of these facts, too, a crab tank filter and thus in particular also the bacteria in the filter have to do more cleaning work than a pure fish tank filter. Here, too, the Hamburg mat filter or related designs, some of which have electric pumps, offer enormous advantages. When equipped with fine-pored sponges, this bioreactor has sufficiently large areas for the creation of biologically active zones, which can then also be visited by the crabs. The actual operators of the filter, the bacteria, live in the sponges.

In the crab aquarium there should always be enough suitable macro and trace elements to ensure the survival of the CPOs. Cancers have an increased need for minerals in order to be able to build their exoskeleton , which essentially consists of calcium and magnesium . Especially in the run-up to the moults, which become less with age, enough minerals must be available in order to be able to form a new, healthy lower armor. Shedding problems, which can also lead to death, are often caused by an insufficient supply of minerals and an associated unsuitable alkaline pH value, which should range from seven to nine.

Weekly partial water changes are necessary for crabs in order to provide good ventilation and fresh water supply, as in the Lago de Pátzcuaro. With its moving surface, the lake constantly brings oxygen into the water. This constant process must also be guaranteed in the aquarium, there with artificial aids. Many aquarists use an oxidizer that continues to work even if the filter fails.

Lining

The omnivorous crabs eat a lot. They are usually fed with the commercially available crab and shrimp food in tubes and cans. But every common fish food is also taken. In addition to spirulina , mud tube worms ( Tubifex tubifex ), enchytra , grindal worms, mosquito larvae and daphnia are also very popular . These feeds can be purchased dried or frozen and are a popular treat for fish too. Often the crabs try to grab their favorite food with the scissors when they sink. Some aquarists breed worms, larvae and small crustaceans themselves and feed them fresh. The specialist trade offers plenty of material for this. In the case of wild catches, nature conservation laws must be observed. There is also the risk of fatal diseases entering the pool. Crustaceans need far more animal proteins than other species. Nevertheless, it recommends that you also offer organic, clean fallen leaves (beech, oak, walnut, hazelnut) in the aquarium. Here you can buy something similar in specialist shops. The leaves are a place to hide and offer young animals in particular a good starter feed. It should be kept in the aquarium, because the microorganisms that cause the decay process of the leaves also provide the adult animals with an important natural source of food. Feeding scalded nettle leaves or vegetables is also possible. A one-day diet does not harm Cancer, it is advisable to take a fasting day once a week. Anyone who keeps crabs and observes them will quickly notice what different preferences the individual animals have.

behavior

The behavior of the CPO is gender dependent. Basically, the animals are relatively peaceful, even if the males can often be much more active and sometimes become more aggressive in the adult stage as soon as competition comes into play. The females are usually a bit calmer and more reserved. However, this can change during the gestation period. Overall, despite this rough classification, it can be said that there are more restrained male crabs, as well as more energetic, very active female specimens. Many CPOs are curious and watch their environment closely. Some are also not afraid to take a close look at water changes and interventions. Some male and female animals threaten people who want to observe them, while others show fearful or waiting behaviors. Here the individual behavior of the Kebse becomes clear.

Socialization

In a community aquarium, care should always be taken to ensure that not too many crabs colonize the tank, as otherwise there may be discord between the crabs themselves and between the crabs and other species with fatal consequences. All animals must be given enough leeway to prevent aggression and competitive behavior. In addition, the animals must not be constantly disturbed in their natural behavior. Fewer animals or animal species is therefore always better to be too many. Stress, which can also be fatal, should be avoided. Since socialization is sometimes more difficult for these reasons, Geck and Schliewen advise to forego a community pool. They emphasize that the crabs may not be able to get to the food offered due to their reluctant nature. A targeted supply of feed to the crabs must therefore be taken into account when planning a community pool. Especially with young animals and butter crabs. Special crab feed can also be served with tweezers, for example.

shrimp

In well-planted tanks, dwarf shrimp can be kept together despite different experiences, although individual animals can obviously be injured and eaten by the crabs. Due to the rather peaceful attitude of the CPOs, the predator-prey ratio may play less of a role here than competitive behavior. Pekny and Lukhaup also state that small shrimp of the genus Caridina should not be socialized. They were also able to observe how crabs tried to mate with the shrimp in a tank densely populated with shrimp, whereby shrimp were often damaged, limbs lost or ultimately also eaten. Both aquarists advise against socialization with large-arm shrimp. Especially during the molting or during the time as vulnerable crayfish, it was already established that shrimp species of the genus Macrobrachium also killed adult Procambarus species, which are much larger than dwarf crayfish.

fishes

In 1998, the Federal Ministry of Food and Agriculture set up the current requirement profile for keeping freshwater ornamental fish. It was found that 54 liters are to be regarded as the absolute minimum for permanent keeping. Most fish that are on the bottom or sleep there should also not be kept with crabs. Even if the crabs usually do nothing to these fish, the armored animals are very curious and can cause damage if they are frightened. This does not apply to some ground-exploring catfish species, such as the ear grated catfish . The good-natured, albeit sometimes frightening, animals sometimes even allow it if a CPO eats next to them or crabs climb over them. Other fish, as long as they do not chase the crabs, are also suitable, especially those that prefer the middle water zones. In general, it can be said that fish usually remain undisturbed by the crabs. However, even larger sick or injured fish lying on the bottom are considered prey by some dwarf crayfish. In general, aquarists have to adapt the number of fish and fish species clearly to the crab tank to be stocked. Less is mostly more. The welfare of the animals always comes before the observer wants to be able to constantly observe interesting and varied things in the pool. The more species are kept in a tank, the more space the animals need and the more complicated keeping them. When planning, it should be taken into account that all fish species used, such as crabs, have a relatively high degree of adaptation to the water values.

Other cancers

Serious aquarists should not keep a second, different type of cancer next to the CPOs in the same tank, as this can create unnecessary competition with death consequences. It should be remembered that the CPOs did not know of any other types of cancer in their original homeland. It is important to target the individual animal species with the respective feed.

Crayfish that do not come from South and North America must never be socialized. Because the native crabs, which also include the orange pygmy crayfish, carry the cancer plague pathogen with them, against which they are immune. However, crabs from Asia, Europe and Australia have nothing to counter this disease. You must not come into direct or indirect contact with these crabs, for example by using the same landing net. Therefore, American crabs must never be released in domestic waters. Scientists in Hungary discovered a population of the orange Cambarellus patzcuarensis as early as 2017 . There the animals had apparently been released in the Lukács thermal baths in Budapest in an approximately 8 × 14 meter outdoor pool and had reproduced. The water temperature in the pool is between 31 and 37 degrees Celsius throughout the year. The scientists captured 26 juvenals and 15 adults. The adults had body lengths between 2.90 and 3.80 centimeters. When a 400 meter long section of the adjacent Danube bank was observed, two adult males were caught.

breed

Female carrying eggs

If the above requirements are met, mating will occur relatively soon. This happens after the female has molted. In this mating, the male "forcibly" turns the female on its back and holds it with the scissors. Pairing can take a few minutes to hours. Four to 30 days later, the female carries eggs to the pleopods. If the eggs are gray, greenish, or white, they are fertilized. Orange eggs are unfertilized and are shed by the female after a while. The young crabs hatch after about three to five weeks. If you don't want to raise them specifically, you can leave them in the pool. If there are enough narrow hiding spots and sludge there, some of them may survive. The parent animals chase after their offspring, but above all the young animals are cannibalistic to one another.

literature

  • Fernando Walter Bernal-Brooks: La Limnología del Lago de Pátzcuaro. Una visión alternativa a conceptos fundamentales. National Autonomous University of Mexico (2002), printed dissertation.
  • Roland Blankenhaus: CPO - Cambarellus patzcuarensis "Orange" . In: Amazonas 27 (2010); Pp. 28-35.
  • Fernando de Buen: El Lago de Patzcuaro. Recientes estudios limnológicos. In: Revista Geográfica , 1 (1941), pp. 20-44.
  • Rosaura Mayén-Estrada, Antonieta Aladro-Lubel: Epibiont Peritrichids (Ciliophora: Peritrichida: Epistylididae) on the Crayfish Cambarellus Patzcuarensis in Lake Pátzcuaro, Michoacán, Mexico. In: Journal of Crustacean Biology 2 (2001); Pp. 426-434.
  • Antonio Lot, Alejandro Novelo: Vegetacion y flora acuatica del lago de Patzcuaro, Michoacan, Mexico. In: The Southwestern Naturalist , 2 (1988), pp. 167-175.
  • Chris Lukhaup , Reinhard Pekny : Crabs in the aquarium. Keeping and care in fresh water. Dähne, Ettlingen 2008, ISBN 978-3-935175-31-9 , pp. 105-107.
  • Miguel Rodríguez Serna, Verónica Gallardo-Pineda, Claudia Carmona-Osalde, Guillermo Blancas-Arroyo: Efecto de la temperatura sobre el crecimiento, supervivencia y reproducción de juveniles de Cambarellus patzcuarensis . In: Revista AquaTIC , Revista científica de la Sociedad Española de Acuicultura, 42 (2015), pp. 17-27.
  • Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133.
  • Alejandro Villalobos: Estudios de los Cambarinos Mexicanos, I. Observaciones sobre Cambarellus montezumae (Saussure) and Algunas de sus Formas con Descripción de una Subspecie Nueva. Anales del Institute de Biologia, Universidad Nacional Autonoma de Mexico, 14 (2), pp. 587–611, 1943 (first description as Cambarellus montezumae patzcuarensis )

Web links

Commons : Striped Crayfish ( Cambarellus patzcuarensis )  - Collection of pictures, videos, and audio files

Remarks

  1. ^ Theodor CH Cole : Dictionary of invertebrates / Dictionary of Invertebrates. Latin - German - English. Springer, Berlin, Heidelberg 2017, ISBN 978-3-662-52868-6 , p. 228.
  2. ↑ IUCN: Cambarellus patzcuarensis
  3. ↑ a b c d e f g h Hans A. Baensch , Hans-Georg Evers : Aquarien-Atlas Volume 6, Mergus, Melle 2002, ISBN 3-88244-068-6 , p. 1154.
  4. ↑ a b Chris Lukhaup , Reinhard Pekny : Crayfish in the aquarium. Keeping and care in fresh water. Dähne, Ettlingen 2008, ISBN 978-3-935175-31-9 , pp. 105-108; here: p. 106.
  5. ↑ a b c Chris Lukhaup , Reinhard Pekny : Krebse im Aquarium. Keeping and care in fresh water. Dähne, Ettlingen 2008, ISBN 978-3-935175-31-9 , pp. 105-108; here: p. 105.
  6. ↑ a b c Ulrich Schliewen : Aquarium fish from A to Z (= The large GU compass ): Gräfe and Unzer, Munich 2011, ISBN 978-3-8338-2191-2 , p. 238.
  7. ↑ a b c d Ulrich Schliewen: Small aquariums - 60 liters. GU animal guide. Gräfe and Unzer, Munich 2009, ISBN 978-3-8338-1167-8 , p. 26.
  8. ↑ a b c d e Chris Lukhaup , Reinhard Pekny : Crabs in the aquarium. Keeping and care in fresh water. Dähne, Ettlingen 2008, ISBN 978-3-935175-31-9 , pp. 105-108; here: p. 107.
  9. ↑ The color vision of birds. Spectrum of Science 12, 2006
  10. ↑ Map of the distribution area on iucnredlist.org, accessed on January 21, 2014
  11. ↑ Fernando Alvarez, Marilú López-Mejía, Carlos Pedraza Lara (2010): Cambarellus patzcuarensis at www.iucnredlist.org
  12. ↑ Miguel Rodríguez Serna, Verónica Gallardo-Pineda, Claudia Carmona-Osalde, Guillermo Blancas-Arroyo: Efecto de la temperatura sobre el crecimiento, supervivencia y reproducción de juveniles de Cambarellus patzcuarensis . In: Revista AquaTIC , Revista científica de la Sociedad Española de Acuicultura, 42 (2015), pp. 17-27; here: p. 18.
  13. ^ J. Platt Bradbury: Limnologic history of Lago de Pátzcuaro, Michoacán, Mexico for the past 48,000 years. Impacts of climate and man . In: Palaeogeography, Palaeoclimatology, Palaeoecology 163 (2000), pp. 69-95; here: p. 69.
  14. ^ Antonio Lot, Alejandro Novelo: Vegetacion y flora acuatica del lago de Patzcuaro, Michoacan, Mexico. In: The Southwestern Naturalist , 2 (1988), pp. 167-175; here: p. 167.
  15. ↑ a b c Antonio Lot, Alejandro Novelo: Vegetacion y flora acuatica del lago de Patzcuaro, Michoacan, Mexico. In: The Southwestern Naturalist , 2 (1988), pp. 167-175; here: p. 171.
  16. ↑ a b c d Antonio Lot, Alejandro Novelo: Vegetacion y flora acuatica del lago de Patzcuaro, Michoacan, Mexico. In: The Southwestern Naturalist , 2 (1988), pp. 167-175; here: p. 170.
  17. ^ A b Antonio Lot, Alejandro Novelo: Vegetacion y flora acuatica del lago de Patzcuaro, Michoacan, Mexico. In: The Southwestern Naturalist , 2 (1988), pp. 167-175; here: p. 169.
  18. ↑ Fernando Walter Bernal-Brooks: La Limnología del Lago de Pátzcuaro. Una visión alternativa a conceptos fundamentales. National Autonomous University of Mexico (2002), Printed Dissertation, p. 27.
  19. ↑ Lenin E. Medina-Orozco, Norma E. García-Calderón, Felipe García-Oliva, Elena Ikkonen: Suelos de humedal del lago de Pátzcuaro, Michoacán, México. In: Tecnología y Ciencias del Agua 5 (2014), pp. 111-124; here: p. 111.
  20. ↑ Fernando Walter Bernal-Brooks: La Limnología del Lago de Pátzcuaro. Una visión alternativa a conceptos fundamentales. National Autonomous University of Mexico (2002), Printed Dissertation, p. 17.
  21. ↑ Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: p. 116.
  22. ↑ Javier Sánchez-Chávez, Luis Bravo-Inclán, Cecilia Tomasini-Ortiz, Fernando Bernal-Brooks: Calidad del agua del lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 27-46; here: p. 36.
  23. ↑ Fernando Walter Bernal-Brooks: La Limnología del Lago de Pátzcuaro. Una visión alternativa a conceptos fundamentales. National Autonomous University of Mexico (2002), Printed Dissertation, p. 17.
  24. ↑ Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: p. 119.
  25. ↑ Sergio Vargas, Nohora Beatriz Guzmán Ramírez: Deterioro de la cuenca del lago de Patzcuaro. Cambios en la identidad étnica p'urhépech. 27. Congreso de la Asociación Latinoamericana de Sociología. 8. Jornadas de Sociología de la Universidad de Buenos Aires. Asociación Latinoamericana de Sociología, Buenos Aires 2009, pp. 1–2.
  26. ↑ Rosaura Mayén-Estrada, Antonieta Aladro-Lubel: Epibiont Peritrichids (Ciliophora: Peritrichida: Epistylididae) on the Crayfish Cambarellus Patzcuarensis in Lake Pátzcuaro, Michoacán, Mexico. In: Journal of Crustacean Biology 2 (2001); Pp. 426-434; here: p. 427.
  27. ↑ Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: p. 99.
  28. ↑ Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: pp. 99–100.
  29. ↑ a b Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: p. 100.
  30. ↑ Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: p. 107.
  31. ↑ Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: pp. 108-109.
  32. ↑ a b Miguel Rodríguez Serna: Análisis ecológico y poblacional de la especie "Cambarellus patzcuarensis" del Lago de Pátzcuaro. In: Rubén I. Huerto Delgadillo, Sergio Vargas Velázquez (eds.): Estudio ecosistémico del lago de Pátzcuaro. Aportes en gestión ambiental para el fomento del desarrollo sustentable. 2, Instituto Mexicano de Tecnología del Agua, Progreso 2014, ISBN 978-607-7563-87-7 , pp. 95-133; here: p. 111.
  33. ↑ Miguel Rodríguez Serna, Verónica Gallardo-Pineda, Claudia Carmona-Osalde, Guillermo Blancas-Arroyo: Efecto de la temperatura sobre el crecimiento, supervivencia y reproducción de juveniles de Cambarellus patzcuarensis . In: Revista AquaTIC , Revista científica de la Sociedad Española de Acuicultura, 42 (2015), pp. 17-27; here: p. 17.
  34. ↑ Miguel Rodríguez Serna, Verónica Gallardo-Pineda, Claudia Carmona-Osalde, Guillermo Blancas-Arroyo: Efecto de la temperatura sobre el crecimiento, supervivencia y reproducción de juveniles de Cambarellus patzcuarensis . In: Revista AquaTIC , Revista científica de la Sociedad Española de Acuicultura, 42 (2015), pp. 17-27; here: p. 26.
  35. ^ Federal Ministry of Justice and Consumer Protection / Federal Office of Justice: Animal Protection Act.
  36. ↑ Federal Act on the Protection of Animals (Animal Protection Act - TSchG)
  37. ^ Animal Welfare Act of December 16, 2005 (TSchG)
  38. ↑ Cancers feel pain too. In: Scinexx. The knowledge magazine.
  39. ↑ a b c Jakob Geck, Ulrich Schliewen: Nano aquariums from 12 to 35 liters. (= GU Tierberater ), Gräfe and Unzer, Munich 2008, ISBN 978-3-8338-1269-9 , p. 39.
  40. ↑ Ulrich Schliewen : Fascinating Aquarium. This is how the fish feel good . Gräfe and Unzer, Munich 2016, ISBN 978-3-8338-4851-3 , p. 127.
  41. ↑ a b Jakob Geck, Ulrich Schliewen: Nano-Aquariums. Wonder world in mini format up to 35 liters. , Gräfe and Unzer, Munich 2017, ISBN 978-3-8338-5516-0 , p. 40.
  42. ↑ a b c Reinhard Pekny ; Chris Lukhaup : Freshwater Prawns (= GU Tierberater ), Gräfe and Unzer, Munich 2008, ISBN 978-3-8338-1196-8 , p. 46.
  43. ↑ Chris Lukhaup , Reinhard Pekny : Crabs in the aquarium. Keeping and care in fresh water. Dähne, Ettlingen 2008, ISBN 978-3-935175-31-9 , pp. 105-108; here: p. 108.
  44. ↑ Jakob Geck, Ulrich Schliewen: Nano aquariums. Wonderful world in mini format up to 35 liters. , Gräfe and Unzer, Munich 2017, ISBN 978-3-8338-5516-0 , p. 45.
  45. ↑ Federal Ministry of Food and Agriculture: Keeping ornamental fish (fresh water).
  46. ↑ András Weiperth, Blanka Gál, Pavlína Kuříková, Martin Bláha, Antonín Kouba, Jiří Patoka: "Cambarellus patzcuarensis" in Hungary: The first dwarf crayfish established outside of North America. In: Biologia 72/12 (2017), pp. 1529-1532.