Dates and Facts

Nomenclature

Triops (singular: Triops/Plural:Triops, greek: three-eyed) are said to be the oldest popular genus which is still unextinct. Primarily Franz Paula von Schrank entitled the Species, he called it Apus. The name Triops has been established in 1955 by A.R. Longhurst, because an avian genus had already been discribed as Apus.

Classification

Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Branchiopoda
Order:	Notostraca
Family:	Triopsidae
Genus:	Triops

Habitat

Triops can principally b e found in the arid areas on earth. Arid means that more water evaporates during the year than rain falls. A typical exam ple is North Africa. The most time in year it's not rainig at all in semi-deserts or steppe. Its raining only during a few months - but then that much that whole areas are afloat and build big pools. Here hatch and grow Triops. This pools exist usually only one or two months in steppe or semi-desert because they run dry when the rain abates.
Another example for this clime is the South of USA. Also here it's raining very rarely. But when it rains it rains that much that pools can be build.
Its very similar in Australia.
In Europe and Asia are Triops too but under different conditions. There is a colder clime and it's more rainy (humid) because of that the pools do longer exist. Though they also run dry or freeze so they're not ready for Triops all the time.
Only in Japan it's like in USA, North Africa or Australia. The paddies there are floated two times a year so the Triops can hatch.

Lifecycle

Triops and other primeval shrimps are one of the less water creatures which mainly live in arid areas on earth. The pools which appear up to two times a year do mostly run dry. So Triops have to create a strategy to "survive" the dehydration. The solution is called resting eggs.
When a Triops gets sexually mature it begins to "lay eggs". Those eggs don't hatch as long as the pool is filled with water. Also when the pool is dry they rest. It's possible that the pools which include the eggs are dry for years. But when the rain finally falls they hatch to hundreds within one day. Those Eggs are able to survive decades without light, food, O2, and Water. Some eggs survive millenia or even more.
The nauplii develop within one day to little Triops. Now the growth continues rapidly.Within the next week, the Triops will shed its skin several times, and grow to about 1.5 cm. This is possible because the Triops has a very fast metabolism and ca n eat all day. In this week the number of Triops will be drastic reduced. Weaker and smaller animals are eaten, so it depend s on the size of the pool how much animals survive. After about two weeks, the Triops is sexually mature. Some species have males and females in approximately equal numbers (gonochoric), and other species can fertilize itself and fertilize eggs without males.
The rest of its life a Triops spents time with laying as many eggs as possible. It is also growing steadily, in the end up to 10 cm. Some species ev en more.
After one tot two months the pools runs dry. Then all Triops die. But even if it didn't run dry they would die anyway because of their rapid metabolism and the fast growth. They would never survive.
The life cycle seems to be quite successful. In the puddle Triops have no natural enemies. Except of birds fo r which triops are a real treat. But that's just not really bad for Triops: Because the eggs are so resistant that birds excrete the eggs without harming them. So they reach the next pool.
With this strategy they survived over 200Mio. years almost without evolutionary changes.

Reproduction

Triops have to develop very fast because of their habitat, so the females have eggs in their brood pouches after ab out 14 days. In those the eggs will get fertilized. But there are two ways for fertilization: the female is able to fertilize the eggs by a hermaphroditic gland (autogamy), or it needs a male for fertilization (gonochorism). This varies from species to species, but the species you can mostly buy in shops is autogamous. So males are very rare. When they appear they are some kind of "DNA-Mixer " to av oid copies of the females in the next breed. The eggs are often colored in red-brown or they can be rose or almost white in some species. After the eggs matured one day, they are layed. For laying eggs the triops looks for a secluded place, preferably in corners or under rocks. So conspecifics can't find eggs to eat them.
Egg-Laying occurs in the following way: After the Triops was looking for a suitable place, it begins to dig. It often digs very deep holes in the sand, but it is faster and more powerful than you think its capable of. After about ten minutes, his work is completed. Now it squeezes the eggs out of its brood pouches and distrubutes them in a whole. An adul t Triops can lay about 100 eggs a day. After distributing all eggs the Triops "glues" the eggs with the sand. It uses a endogenous secretion which it puts on the eggs and glues them with the sand to little chunks. After all it fills up the whole so the eggs are ideal protected from natural enemies.
If thee pool ran dry the eggs will be protcted from sun and wind. And if its filled with water again, the eggs will hatch again.

Difference between male and female

The differences between male Triops and female Triops are small. Only the trained eye of a triopsbreeder is able to differentiate males and femals. First there is only one undoubted difference between males and females: The male has no brood pouches. This is the only feature that the two sexes differ from each other clearly. But when you look closer, there are also other differen ces. The male has a significantly smaller carapce compared to the female but a much longer tail. Because of the smaller carapace the legs can be seen better compared to the female. Another difference is the color. Males are generally

less c olored than females. In the American species Triops longicaudatus males are even mostly complete colored rose.

Mating

The mating is something that only a very few Triopsbreeder can see live. It occurs almost exclusively in the types who need a male for reproduction.( gonochoric species)
During pairing, the male swims to the female and bends around it. The female does the same. Both stay like this about five seconds, then the mating is over. During this time the male has fertilized the eggs of the female. Thereafter, the male is relatively quick able to fertilize more females.

Anatomy

The Triops has no skeleton made ​​of bone instead it has an exoskeleton made ​​of chitin like insects and crustaceans. This gives the Triops high stability, but it has a disadvantage: the chitin does not grow. Therefore, a Triops in young age shed its skin each day, a old er weekly and underneath can grow a new, larger one.
The Triops has not really a brain but it has some nerve cords which work sensory input and control its movements. It also has a simple heart and an open circulatory system. That means that all the blood circulates openly in its body. If a Triops bleeded, all blood would ru nd out of the Triops.

Behavior pattern

The Triops is a geobiont of tem porary waters. The most time in its life he spends with digging in sand and eating. He really swims rarely. Usually it crawls with its legs on the ground. Sometimes the Triops swims on his back on the water surface. It is believed that he is doing that for searching food (mosquitoes or flies), oror to get UV light. Both points are very possible. The Triops is perfectly adapted to digging in the sand and swimming, . It has very large claws, with w hich it can displace a lot of sand. It also uses the front part of its skull plate to shore while laying eggs in the sand.Its b ody is very hydrodynamic perfe ct t o swim. On the carapace are small bulges which divert the water from the body. The tail is used to naviagation: up, down, left and right. The furca stabilizes the swimming process. The Triops can actually live only in water. Neither it's possible to get out of water by itself, nor it's possible for it to live out of water.

Food

Triops are om nivores that means that they eat everything eatable. They eat anything they get their and anything which is not greater than thems elves. That may be leafs, it can be worms and other small animals and it may be conspecifics. But a Triops al ways needs proteins to shed. It's not enough to eat plants like other primeval shrimps do. He also needs meat.

Disease and dysfunction

Triops can get sick - just like any living being. They are prone to bacteria or fungi, or have physical dysfunct ion. Triops are also prone to different pa rameters in water. Substances, such as nitrite and ammonia are harmful for Triops in high doses . When a Triops is intoxicated with nitrite, it gets a red head. An intoxication with nitrite may cause death after a few hours. If the value of nitrite is to high you should change 50% of water. An ammonia poisoning is similar, except that this material is even more aggressive. The water composition is very important for Triops. Heavy metals and chlorine should not be in the aquarium water, also a constant water hardness is required.If these conditions do not agree 100% (which happens often), Triops react very badly and die (mostly they discolor before). Some people consider its better to keep Triops in distilled water, because there are really constant conditions and you know exactly what is in the wa ter and what is not. Another case is the temperature: it should be rather too low than too high. A too high temperature can cause fatal consequences: The water is not to able to save oxygen. It escapes - and the Triops suffocates. Oxygen can also disappear sudden ly when there's much waste such as food left in tank: the resulting bacteria consume all the oxygen in the tank. Mold is a risk in any aquarium. Triops die very quickly in case of fungi. Usually they turn green before. A daily risk is shedding its skin. A breeder cant help his Triops: Also healthy Triops can make a wrong move while shedding and the result is it quickly dies because of an blister filled with blood. Also it may happen that the Triops can't shed its old skin completely. Then he is stuck in it and dies very soon - either from exhaustion or suffocation. You're always confronted with death in breeding Triops. When someone has a problem with that should think about breeding Triops.

Sources

• some picture are from the movie: "Tod auf Zeit" by ORCA Naturfilmproduktion
• some pictures are from Bene
• some pictures are from Adri
• some pictures are from Bettina & Rabea
• some pictures are from Crash
• some pictures are from heroldini
• Some pictures are from KaDDy