Chaudhuriidae, is a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of small freshwater

eel Eels are ray-finned fish belonging to the order Anguilliformes (), which consists of eight suborders, 19 families, 111 genera, and about 800 species. Eels undergo considerable development from the early larval stage to the eventual adult stage ...

-like

fish Fish are aquatic, craniate, gill-bearing 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. Approximately 95% of ...

related to the

swamp eel The swamp eels (also written "swamp-eels") are a family (Synbranchidae) of freshwater eel-like fishes of the tropics and subtropics. Most species are able to breathe air and typically live in marshes, ponds and damp places, sometimes burying the ...

s and

spiny eel The name spiny eel is used to describe members of two different families of fish: the freshwater Mastacembelidae of Asia and Africa, and the marine (and generally deep sea) Notacanthidae. Both are so-named because of their eel-like shape and stur ...

s, commonly known as the earthworm eels. The known

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

are literally the size and shape of

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. T ...

s, thus the family name. While one species, ''Chaudhuria caudata'' was reported from the

Inle Lake Inle Lake (, ), a freshwater lake located in the Nyaungshwe Township of Shan State, part of Shan Hills in Myanmar (Burma). It is the second largest lake in Myanmar with an estimated surface area of , and one of the highest at an elevation of ...

Nelson Annandale Thomas Nelson Annandale CIE FRSE (15 June 1876, in Edinburgh – 10 April 1924, in Calcutta) was a British zoologist, entomologist, anthropologist, and herpetologist. He was the founding director of the Zoological Survey of India. Life The eld ...

in 1918, the others have been only recently reported (since the 1970s), all in the eastern

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

area, from

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

Korea Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...

Neither the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

nor anal fins have spines, and in ''Nagaichthys'' and ''Pillaia'' they have fused with the

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

; in the other genera, the caudal is small but separate. Their bodies have no scales. The few specimens found to date have been no longer than 8 cm, and ''Nagaichthys filipes'' is only known to reach 3.1 cm. The eyes are small, covered in thick skin.Britz, R. (2003): Descriptive Osteology of the Family Chaudhuriidae (Teleostei, Synbranchiformes, Mastacembeloidei), with a Discussion of Its Relationships. ''American Museum Novitates, 3418: 1-62.'' Almost nothing is known of the habits and biology of the earthworm eels. The family name "Chaudhuriidae" comes from a Burmese local name for a fish.

References

Chaudhuriidae {{Synbranchiformes-stub