The Mastacembelidae are a family of fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

es, known as the spiny eels. The Mastacembelids are part of the Order Synbranchiformes

Synbranchiformes

Synbranchiformes, often called swamp eels, is an order of ray-finned fishes that are eel-like but have spiny rays, indicating that they belong to the superorder Acanthopterygii.-Taxonomy:...

, the swamp eels, which are part of the Actinopterygii

Actinopterygii

The Actinopterygii or ray-finned fishes constitute a class or sub-class of the bony fishes.The ray-finned fishes are so called because they possess lepidotrichia or "fin rays", their fins being webs of skin supported by bony or horny spines , as opposed to the fleshy, lobed fins that characterize...

 (ray-finned fishes).

In an evaluation of the family in 2004, the subfamilies of Mastacembelidae were found to not be well supported and were rejected. Also, the genera Caecomastacembelus and Aethiomastacembelus were placed in synonymy with Mastacembelus.

These fish originate from Africa

Africa

Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

, Southeast Asia

Southeast Asia

Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...

, and South Asia

South Asia

South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries to the west and the east...

. Spiny eels generally inhabit soft-bottomed habitats in fresh and brackish water. Some species burrow in the substrate during the day or for certain months and have been found buried in soil in drying periods.

These fish have an eel

Eel

Eels are an order of fish, which consists of four suborders, 20 families, 111 genera and approximately 800 species. Most eels are predators...

-like body. Some of these fish can reach a maximum length of about 1 metre (40 in). Very characteristic of this group is the long nose appendage with two tubulated nostrils. Mastacembelids have a series of well-separated dorsal spines on their back, hence the name of their family, spiny eels.

In some areas these fish are regarded as food fish. Several species of Mastacembelidae are aquarium

Aquarium

An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

 fish, such as the fire eel

Fire eel

The fire eel is a large freshwater fish found in Cambodia, Indonesia, Laos, Malaysia, Thailand, and Vietnam.-Description:...

.