Chinese Giant Salamander

Chinese Giant Salamander

Phylum : Chordata
Class : Amphibia
Order : Caudata
Family : Cryptobranchidae
Genus : Andrias
Species : davidianus

Length : 40in (1m)
Weight : 25lb (11kg)

IUCN Status : Critically Endangered

The Chinese Giant Salamander is the largest Salamander species in the entire world. Individuals measuring 6ft (1.8m) have been recorded, though most specemins today around only around 3ft (.9m).

Chinese Giant Salamanders are found in the mountain streams of China, but due to habitat loss, harvesting for food and the pet trade, and the introduction of pesticides, these gigantic amphibians are fragmented in their population and are near extinction. They have been bred in captivity, but very few are actually kept in zoos around the world.

Chinese Giant Salamanders are most active during the night time, when they come out to hunt and feed on fish, small vertebrates, and various types of invertebrate species. They hunt primarily by smell and touch.

During the fall breeding season dozens, if not hundreds of Salamanders congregate and fight over breeding cavities. Females enter these lairs and lay up to 500 eggs, which are then guarded by the male until they hatch about two months later. A newly hatched Chinese Giant Salamander is only 1.2in (3cm) long!

Chinese Giant Salamanders are a long-lived species, and captive individuals have lived over 50 years.

Olm

(Image Source)

Olms are absolutely fascinating creatures with some amazing adaptations for the environment that they live in. You see, they are the only cave dwelling vertebrates found exclusively in Europe, and are found in parts of Slovenia, Croatia, and Bosnia and Herzegovina. Olms are members of a very ancient line of amphibians that diverged from its nearest living relatives during the Jurassic period over 190 million years ago! There are currently six living species in this line, including Mudpuppies.

As mentioned, Olms live in caves, exclusively underwater. Because they live in light-less environments, they lack most pigmentation in their skin, and they have essentially lost their sense of sight (their eyes are actually covered with skin and serve only as basic light sensors). To make up for the darkness, Olms have developed their other senses to an amazing degree. They are able to sense other organisms in the water using a chemical receptor in their taste buds. They are also able to detect different vibrations and sound waves, and even have a sensory organ that lets them register weak electric fields.

Olms have a few more relatively unique characteristics. One is that they remain suspended in a larval state for their entire lives. They retain large gills and a tail fin. The Olm also has a remarkably long lifespan for an amphibian. They might not reach sexual maturity until the age of 15, and individuals have reached 70 or older. They also reproduce externally, and the mother guards her eggs until hatching. The eggs are extremely dependent on the water temperature, and there is one hypothesis that females will hatch their eggs internally if the water is too cold.

Olms are extremely vulnerable to climate change, as their watery underground habitats are directly affected by what is going on on the surface. They are listed by IUCN as endangered.

Mudpuppy

Mudpuppies are among the largest of all Salamanders, and can grow to about 14in in length. They can be found throughout the Eastern United States and Canada, and are completely aquatic. They prefer shallow lakes and streams, though specimens have been found at depths of 100 feet. Mudpuppies spend most of the day hiding under rocks and vegetation. They are carnivorous and feed at night off of insects, crustaceans, small fish, and snails.

Image Source

Necturus maculosus is identified by their brown spotted bodies and bright red gills. It is an interesting species of Amphibian because gills are their one and only method of breathing, unlike many other species of salamander which develop lungs during their metamorphosis. Another pretty unique trait is that Mudpuppies guard their eggs, rather than lay them an abandon them. It takes up to 5 week for eggs to hatch after being laid. Mudpuppies have a lifespan of around twenty years and don't even reach sexual maturity until about five or six.

Mudpuppies are not a threatened species, but habitat loss and pollution has affected some localized populations.

Marbled Salamander

I was given a suggestion to write an article about a salamander. Not a specific salamander, just one of the 500 different species. So I chose this guy! Marbled Salamanders (Ambystoma opacum) are found throughout the Eastern United States, though you won't spot them too often. They are part of the genus Ambystoma, which is commonly known as the mole salamanders. They are nocturnal and spend most of their time hiding underneath things, hence the name. Marbled Salamanders can be spotted during their breeding season, when they take part in some interesting activities.

Image from Reio

What are these activities? Well, the Marbled Salamander is pretty unique in that it doesn't actually lay its eggs underwater. After the males and females mate in the fall, the males disappear off into the wilderness while the females go and find a suitable location to lay her eggs. This area may be a tree, a ditch, anything... just as long as it will eventually be covered with water. She lays her eggs there and guards over them, also a bit unusual for a salamander. When the rain comes, her eggs become submerged and then hatch. If they don't come... then they remain dormant and hatch during the spring wet season. After hatching the young salamanders grow rapidly, sometimes reaching metamorphosis after only a few months.

The Marbled Salamander is named because of the silvery bands that form patterns on their otherwise black bodies. They have long tails that comprise up to 40% of their body length, and they grow to be about 4inches long as adults. They have big appetites and consume (among other things) insects, worms and snails. Marbled Salamander have quite a few predators of their own, and in some local areas their habitats are being threatened by humans. Overall though, they are listed as being of Least Concern due to their wide range and overall stable population trend.

Axolotl

Pronounced Axe-oh-lot-ul, this salamander is native to only one small are of Mexico, Lake Xochimilco. Axolotl's differentiate themselves from other salamanders in that they retain their tadpole-like characteristics throughout their entire lives, specifically the external gills and tail.

Axolotl's are almost extinct in the wild, because, like the previously featured Texas Blind Salamander, their habitat is being threatened. Due to their natural homes being right next to Mexico City, the 2nd most populated city in the world, their watery homes are being used up and polluted. Interestingly though, they are used extensively for scientific research, and are kept as pets in multiple countries, ensuring that the species won't ever become truly extinct for a very long time, if ever.

Image from Wikimedia Commons

Now, just why exactly are Axolotls being used for research? Because they can completely regrow their limbs! Unlike most creatures, who just have to deal with an arm being chomped off, the Axolotl can completely regrow it over time. They are also able to easily retrieve transplants from other specimens and receive full functionality from them. There is also documentation of them regrowing their vital organs, brain segments and spinal chord.

Also previously mentioned was their existence as household pets. I am no expert on their captivity requirements, so I'll just redirect to curious to Axolotl.org, which seems to know what they are talking about.

Texas Blind Salamander

The Texas Blind Salamander lives in only one location in the entire world. Guess where. Texas! Specifically the Edwards Plateau region, (#30 on the map) and more specifically then that, in an aquifer under San Marcos. They require a very clean supply of water, which is being threatened by city growth and pollution. As such, they are listed as vulnerable on the IUCN red list, and the number of specimens in the wild is unknown.

The Texas Blind Salamander lives underground in its aquifer, and as such has evolved to the point of not really needing eyes or skin pigmentation. Those evolved traits are found in many other cave dwelling creatures as well. They obviously live in water, and have large sets of red gills on the sides of their head in order to draw oxygen from it. They grow up to 5 inches in length. Overall they are considered to be the most advanced troglobitic (cave dwelling) species of salamander known. They do not have a set breeding season, as evidenced by observations of young year round, and they feed on tiny blind crustaceans, snails and insects that themselves live off the nutrients in bat droppings. Not much else is known about them because of their underwater, underground habitat, and they are only ever found on the surface when the water pushes them up there.


image from the us fish and wildlife service