''Galactosomum'' 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
flukes in the family
Heterophyidae
Heterophyidae is a family of intestinal trematodes in the order Plagiorchiida.
Description: " Tegument covered by spines. Oral sucker not armed or armed by circumoral spines. Pharynx presented. Genital synus presented. Ventral and genital s ...
. There are currently 28 recognised
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
within the genus. They mainly infect
aquatic
Aquatic means relating to water; living in or near water or taking place in water; does not include groundwater, as "aquatic" implies an environment where plants and animals live.
Aquatic(s) may also refer to:
* Aquatic animal, either vertebrate ...
birds
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...
, but often infest
fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
as
larva
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 ...
e. Three species are known to use
marine mammals
Marine mammals are mammals that rely on marine ecosystems for their existence. They include animals such as cetaceans, pinnipeds, sirenians, sea otters and polar bears. They are an informal group, unified only by their reliance on marine env ...
as hosts.
Description
The excised spherical
metacercaria
Trematodes are parasitic flatworms of the class ''Trematoda'', specifically parasitic flukes with two suckers: one ventral and the other oral. Trematodes are covered by a tegument, that protects the organism from the environment by providing sec ...
is 2.7–4.9 mm long.
Generally, only one is found per fish.
Life cycle
Some species of ''Galactosomum'' cause infected fish to swim closer to the surface and colorfully flash their underbellies.
In fish, symptoms can be similar to those of
whirling disease caused by the unrelated parasite ''
Myxobolus cerebralis''.
Gastropods
Gastropods (), commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda ().
This class comprises snails and slugs from saltwater, freshwater, and from the land. Ther ...
hosting select species suffer from sensory impairment due to infestation. This makes these
prey animals more likely to be consumed by aquatic birds, providing a host for the parasite to reach the mature stage of its life cycle. ''Galactosomum'' cannot survive in human hosts.
Species
*''
Galactosomum baylisi''
(Gohar, 1930)
*''
Galactosomum bearupi''
Pearson, 1973
*''
Galactosomum cochlear''
(Diesing, 1850) Travassos, 1929
*''
Galactosomum cochleariforme''
(Rudolphi, 1819) Pratt, 1911
*''
Galactosomum darbyi''
Price, 1934
*''
Galactosomum dollfusi
''Galactosomum'' is a genus of Trematoda, flukes in the family Heterophyidae. There are currently 28 recognised species within the genus. They mainly infect Aquatic animal, aquatic birds, but often infest fish as larvae. Three species are known t ...
''
Pearson, 1973
*''
Galactosomum echinatum''
(Timon-David, 1955)
*''
Galactosomum erinaceum''
(Poirier, 1886)
*''
Galactosomum fregatae''
(Prudhoe, 1949)
*''
Galactosomum humbargari''
Park, 1936
*''
Galactosomum johnsoni''
(Price, 1934)
*''
Galactosomum lacteum''
(Jägerskiöld, 1896)
*''
Galactosomum linguiforme''
Anantaraman, 1974
*''
Galactosomum nicolai''
(Isaichikov, 1927)
*''
Galactosomum palawanense''
Fischthal & Kuntz, 1972
*''
Galactosomum phalacrocoracis''
Yamaguti, 1939
*''
Galactosomum puffini''
Yamaguti, 1941
*''
Galactosomum renincola''
Pearson, 1973
*''
Galactosomum sanaense''
Kobayashi, 1942
*''
Galactosomum semifuscum''
(Olsson, 1876)
*''
Galactosomum sinuilactis''
Pearson, 1973
*''
Galactosomum spinetum''
(Braun, 1901)
*''
Galactosomum stelleri''
Dailey, Demaree & Critchfield, 2002
*''
Galactosomum timondavidi''
Pearson & Prévot, 1971
*''
Galactosomum ubelakeri''
(Dailey, 1969) Pearson, 1977
*''
Galactosomum ussuriense''
Oshmarin, 1963
*''
Galactosomum witenbergi''
Anantaraman, 1974
*''
Galactosomum yehi''
(Dissanaike, 1961) Pearson, 1973
References
External links
Heterophyidae
Suicide-inducing parasitism
Plagiorchiida genera
{{Trematoda-stub