''Chonopeltis'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of fish lice in the subclass

Branchiura The family Argulidae, whose members are commonly known as carp lice or fish lice, are parasitic crustaceans in the class Ichthyostraca. It is the only family in the monotypic subclass Branchiura and the order Arguloida, although a second family ...

. These

crustaceans Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of Arthropod, arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquat ...

are

ectoparasitic Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The en ...

freshwater fish

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County * Host Island, in the Wilhelm Archipelago, Antarctica People * ...

. Species of this

are exclusively found in rivers in Africa.

Description

Members of this

do not grow any larger than a few millimetres. They have flat bodies covered by a

carapace A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the unde ...

, and have two large suction cups, one on either side their heads. These suction cups are used to attach to their hosts. ''Chonopeltis'' feed on various tissues, including mucus, internal fluids, and sloughed-off scales. The genus ''Chonopeltis'' is distinguished from the genus '' Argulus'' due to its lack of a preoral spine and from ''Dolops'' by the presence of suckers rather than hooks.

Reproduction and life cycle

Mating and

larval A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

development of ''Chonopeltis'' occur on the host.

Gravid In biology and medicine, gravidity and parity are the number of times a female has been pregnant (gravidity) and carried the pregnancies to a viable gestational age (parity). These two terms are usually coupled, sometimes with additional terms, t ...

females do not leave the host to lay eggs, as they are poor swimmers. This is in contrast to other members of 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 ...

Argulidae The family Argulidae, whose members are commonly known as carp lice or fish lice, are parasitic crustaceans in the class Ichthyostraca. It is the only family in the monotypic subclass Branchiura and the order Arguloida, although a second famil ...

, who must leave their hosts to mate. Unlike many other crustaceans, female ''Chonopeltis'' do not carry the fertilised eggs in an egg sac, but they deposit their eggs on a

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (aquatic environment), the earthy material that exi ...

. To lay they eggs, the females do not leave the fish host, but lean off.

Species

As of December, 2022, there are 12 species recognised in the genus ''Chonopeltis'': *'' Chonopeltis australis'' *'' Chonopeltis brevis'' *'' Chonopeltis congicus'' *'' Chonopeltis elongatus'' *'' Chonopeltis flaccifrons'' *'' Chonopeltis fryeri'' *'' Chonopeltis inermis'' *'' Chonopeltis lisikili'' *'' Chonopeltis liversedgi'' *'' Chonopeltis meridionalis'' *'' Chonopeltis minutus'' *'' Chonopeltis schoutedeni'' The species ''Chonopeltis minutus'' may be

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

as it has not been observed since 1974.

References

{{Taxonbar, from=Q18583595 Crustacean genera