Potamogalidae is the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

of "otter shrews", a group of

semiaquatic In biology, being semi-aquatic refers to various macroorganisms that live regularly in both aquatic and terrestrial environments. When referring to animals, the term describes those that actively spend part of their daily time in water (in ...

riverine afrotherian

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s indigenous to

sub-Saharan Africa Sub-Saharan Africa is the area and regions of the continent of Africa that lie south of the Sahara. These include Central Africa, East Africa, Southern Africa, and West Africa. Geopolitically, in addition to the list of sovereign states and ...

. They are most closely related to the tenrecs of

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

, from which they are thought to have split about 47–53 million years ago. They were formerly considered a subfamily of Tenrecidae. All otter shrews are carnivorous, preying on any aquatic animal they can find with their sensitive whiskers, particularly insects. As their common name suggests, they bear a strong, but superficial resemblance to true

otter Otters are carnivorous mammals in the subfamily Lutrinae. The 13 extant otter species are all semiaquatic, aquatic, or marine. Lutrinae is a branch of the Mustelidae family, which includes weasels, badgers, mink, and wolverines, among ...

s to which they are not closely related, nor are they closely related to true

shrew Shrews ( family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to dif ...

s. They move through the water by undulating their tail in a side-to-side motion similar to the motions made by a crocodile swimming.

Morphology

Otter shrews have small eyes and ears, consistent with the features of nearly all shrews. They have a broad, flat, muzzle that is substantially covered with sensitive whiskers and ends in a leathery pad. The margins of the hind feet have fringes of skin, and the second and third toes are fused. All species of otter shrews have dense, water repellent fur.

Extant species

Only three species of otter shrew are recognized. Of these, ''P. velox'' has a very broad geographic range, ''M. lamottei'' has a very restricted range, and ''M. ruwenzorii'' is intermediate. Family Potamogalidae * Genus '' Micropotamogale'' (dwarf otter shrews) **

Nimba otter shrew The Nimba otter shrew (''Micropotamogale lamottei'') is a dwarf otter shrew and belongs to the mammal family Potamogalidae. Otter shrews are shrew-like afrotherian mammals found in sub-Saharan Africa. They are most closely related to the tenrecs ...

(''M. lamottei'') ** Ruwenzori otter shrew (''M. ruwenzorii'') * Genus '' Potamogale'' **

Giant otter shrew The giant otter shrew (''Potamogale velox'') is a semiaquatic, carnivorous afrotherian mammal. It is found in the main rainforest block of central Africa from Nigeria to Zambia, with a few isolated populations in Kenya and Uganda. It lives in str ...

(''P. velox'')

Phylogeny

Relations between the various afrotherian orders are still being studied. On the basis of molecular studies, elephants and sirenians appear to be

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

s. Potamogalids are sisters to tenrecids, and next most closely related to chrysochlorids. These findings are compatible with the work of earlier anatomists.

References

Afrosoricida Aquatic mammals Mammal families {{afrosoricida-stub