Esocoidei

Some fish live in fresh water.

They like to hide in thick plants. These fish live in North America and Eurasia.

They have been around for a very long time. They first appeared many millions of years ago. Some of these fish are called pikes. Others are called mudminnows.

They are related to salmon fish. These fish are very old and special. It is fun to learn about them.

Esocoidei is a group of small freshwater fish.

They like to live in places with many weeds. You can find them in North America and Eurasia. This group has two main families. One family is Esocidae. This family includes pikes.

Another family is Umbridae. This family has mudminnows.

The mudminnow genus Umbra is the only one left in its family. These fish are very old. They first appeared during the Cretaceous period. This was a time long ago. They split from salmon fish about 110 million years ago. Some of these fish are now fossils.

One fossil fish is called Palaeoesox. Scientists study how these fish are related. They use genes to learn about them. They also look at old bones. This helps them see how the fish changed over time.

Esocoidei is a special group of small freshwater fish.

They are part of a larger group called Salmoniformes. This group includes two main families. One family is called Esocidae, which includes pikes.

The other family is Umbridae, which has mudminnows. These fish like to live in water filled with weeds. You can find them in North America and northern Eurasia today. They are important for understanding how fish changed over time.

These fish have a long history of changing. They first appeared during the late Cretaceous period. About 110 million years ago, they split from a group called Salmonoidei. This split created two different paths for these fish. The living species we see today came from a common ancestor. That ancestor lived about 90 million years ago.

This long timeline shows how they survived for ages.

Scientists have spent a long time studying these fish. In the past, they were called a suborder. During the early 21st century, experts called them a separate order. They did this because the fish looked very different from salmon.

However, new studies on their family trees changed this. These studies showed they are actually related to salmon. Now, most experts put them back into the Salmoniformes group.

Many fossils help us learn about their past. In North America, fossils like Estesesox and Oldmanesox were found. Scientists also found Archaeosiilik in the same area. These fossils show they lived before a big extinction event. The genus Umbra is the only living part of Umbridae.

It can be found in Europe and eastern North America. Genetic studies show these Umbra species split a long time ago.

We can see how these fish fit into our world. The three living groups are Esox, Novumbra, and Dallia. Together, they live in many parts of the north. This is called a holarctic distribution. They are closely related to the salmon you might know. By looking at genes and old bones, we see the link. This helps us understand the history of life in our waters.

Esocoidei is a small suborder of freshwater ray-finned fish.

This group is one of two suborders within the larger order Salmoniformes. It is highly significant for studying how fish species evolve and diverge over millions of years. The suborder is divided into two distinct families: Esocidae and Umbridae. The Esocidae family contains the pikes, which give the entire order their name.

These fish are typically found in freshwater habitats that are filled with weeds. Today, they live across North America and northern Eurasia.

The history of the esocoids is a long and complex journey. They first appeared during the late Cretaceous period. This was a time of great biological change known as the Euteleostei radiation. About 110 million years ago, they diverged from their sister group, the Salmonoidei. This divergence created two separate evolutionary paths. All living species in the suborder evolved from a common ancestor. This ancestor lived approximately 90 million years ago.

Taxonomy is the science of naming and classifying living things. The classification of Esocoidei has changed as scientists learned more. In the past, they were often placed as a suborder within Salmoniformes. During the early 21st century, researchers changed this. They treated them as their own separate order called Esociformes. This was because they looked morphologically different from salmon. However, modern phylogenetic studies have changed things again. These studies look at evolutionary relationships to build family trees. These studies affirmed the close link between Salmoniformes and Esociformes. Because of this, recent taxonomic authorities have revived the old classification. They now place the esocoids back into the Salmoniformes suborder.

The family Esocidae is quite diverse. It was established by Rafinesque in 1815. This family includes the subfamily Esocinae, which contains the pikes.

It also includes the subfamily Dalliinae. Recent genetic and paleontological research has clarified these relationships. Scientists used to think the family only included the genus Esox. Now, research shows that Novumbra and Dallia are also members of Esocidae. These two genera are more closely related to Esox than they are to Umbra.

The family Umbridae is much smaller in terms of living members. It was established by Bonaparte in 1845. Currently, the genus Umbra is the only living genus in this family.

These are known as mudminnows. They can be found in Europe and eastern North America. Genetic studies on Umbra have revealed a very old split. The North American and European species split during the late Cretaceous and early Paleogene. This means they have been separate for a very long time.

Fossils provide a window into the ancient world of these fish. In North America, several esocid genera are known from the Late Cretaceous. These include Estesesox, Oldmanesox, Archaeosiilik, and Nunikuluk.

These fossils are very important to scientists. They show that esocids were among the few North American freshwater teleost groups to diversify before the Cretaceous-Paleogene extinction event. In Europe, researchers have described three additional genera from Paleocene fossils. This tells us that these fish were successful across different continents and time periods.

Understanding Esocoidei helps us see the broader patterns of life on Earth. The three living genera, Esox, Novumbra, and Dallia, show a holarctic distribution. This means they are spread across the northern parts of the world. By studying the relationship between Esocidae and Umbridae, we learn about evolutionary splits. We see how a single ancestor can lead to many different types of fish. The study of these fish connects biology, geology, and history. It shows how life persists through massive changes in the planet's environment.