''Microcotyle visa'' is a

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 ...

monogenean Monogeneans are a group of ectoparasitic flatworms commonly found on the skin, gills, or fins of fish. They have a direct lifecycle and do not require an intermediate host. Adults are hermaphrodites, meaning they have both male and female reprod ...

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has c ...

on the

gills A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

of a marine

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 li ...

. It belongs to the family

Microcotylidae Microcotylidae is a family of polyopisthocotylean monogeneans.WoRMS (2018). Microcotylidae Taschenberg, 1879. Accessed at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=119247 on 2018-12-03 All the species in this family are parasitic on ...

Systematics

''Microcotyle visa'' was described and illustrated by Bouguerche ''et al''., based on and 31 specimens (including three with molecular information), from the gills of the bluespotted seabream ''

Pagrus caeruleostictus ''Pagrus'' is a genus of fish in the family Sparidae. It contains at least six described species: *''Pagrus africanus'', Southern common seabream (Akazaki, 1962) *'' Pagrus auratus'', Silver seabream or Australasian snapper (Forster, 1801) ...

'' (

Sparidae The Sparidae are a family of fish in the order Perciformes, commonly called sea breams and porgies. The sheepshead, scup, and red seabream are species in this family. Most sparids are deep-bodied compressed fish with a small mouth separated by a ...

) collected at Bouharoune off the Algerian coast. The analysis of the cytochrome oxydase 1 gene of ''Microcotyle visa'' revealed only minor intraspecific variation (1.4%), clearly lower than the distance between this species and other '' Microcotyle'' species (10–15 %). This monogenean is the fourth member of the genus known to parasitise a sparid host. In the same paper, a species of ''Paramicrocotyle'' sp. included in the molecular analysis was nested in a robust ''Microcotyle-Paramicrocotyle'' clade and ''Paramicrocotyle'' was considered a junior synonym of ''Microcotyle''. ''Paramicrocotyle danielcarrioni'' and ''Paramicrocotyle moyanoi'' were transferred to the genus '' Microcotyle''.

Description

''Microcotyle visa'' has the general morphology of all species of '' Microcotyle'', with a symmetrical elongate body and a narrow anterior end, comprising an anterior part which contains most organs and a posterior part called the

haptor The haptor is the attachment organ of the monogeneans, a group of parasitic Platyhelminthes. The haptor is sometimes called opisthaptor (from ''opistho-'': behind) to emphasize that it is located in the posterior part of the body, and to differe ...

. The haptor is subsymmetrical or symmetrical, and bears 59–126

clamps Clamp may refer to: Tools and devices *Brick clamp, an early method of baking bricks *Clamp (tool), a device or tool used to hold objects in a fixed relative position (many types listed) **C-clamp **C-clamp (stagecraft) **Riser clamp, a device u ...

, arranged in 2 equal or sub-equal lateral rows, one on each side. The clamps of the haptor attach the animal to the

gill A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

of the fish. There are also two septate oval buccal suckers at the anterior extremity. The digestive organs include an anterior, terminal mouth, a subspherical pharynx, a long thin

oesophagus The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the ...

without lateral diverticula and a posterior

intestine The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans ...

that bifurcates at level of genital atrium in two lateral branches apparently fused just anterior to the haptor; the left branch extends into haptor. Each adult contains male and female reproductive organs. The reproductive organs include an anterior genital atrium, comprising the anterior atrium proper and two posterior "pockets". The atrium proper is shaped as inverted heart, armed with numerous conical spines of similar sizes; the spines are more dense in the centre than in lateral parts, arranged as one main anterior group and two postero-lateral smaller groups called “pockets”, a

vagina In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...

with a middorsal pore visible in most specimens, posterior to genital atrium, a single complex

ovary The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. ...

and 14–29

testes A testicle or testis (plural testes) is the male reproductive gland or gonad in all bilaterians, including humans. It is homologous to the female ovary. The functions of the testes are to produce both sperm and androgens, primarily testoster ...

, post-ovarian, occurring in 2 rows generally intercaecal, in posterior half of body proper. The eggs are fusiform with long filaments at both ends, often coiled. Three sequences of the cox1 gene has been published.

Etymology

The species name, ''visa'', refers to the happiness of the first author when she obtained her visa, after a period of uncertainty.

Hosts and localities

The type-host is the bluespotted seabream ''Pagrus caeruleostictus'' (

). The identity of fish host was confirmed by barcoding. The type-locality is off

Algeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , relig ...

References

{{Taxonbar, from=Q61182938 Microcotylidae Animals described in 2019 Parasites of fish Fauna of Algeria