You're asking about animals that are both aquatic and terrestrial (meaning they live both in water and on land) and don't have tails. This is a bit tricky, as many animals that live in both environments have tails for balance or swimming.

However, there are some animals that fit this description, but they don't necessarily belong to a single order:

* Amphibians: While many amphibians have tails in their larval stage, some adults, like toads, are tailless and live both in water and on land.

* Some Reptiles: Certain reptiles, like turtles, are aquatic and terrestrial and lack tails.

* Some Mammals: Sea Otters are excellent swimmers but also spend time on land, and they lack tails.

It's important to note that the lack of a tail is not a defining characteristic for any specific order. Many animals within an order may have tails, while others within the same order might not.

To be more precise, you need to specify the type of animal you are interested in (e.g., amphibians, reptiles, mammals).