Microcotyle archosargi

Microcotyle archosargi is a species of monogenean, parasitic on the gills of a marine fish. It belongs to the family Microcotylidae. It was first described by MacCallum in 1913 based on  ten specimens. Hargis (1956) pointed out that the description and figures  given by MacCallum were poor in details.

Systematics
In 1971, Unnithan created the combination Microcotyle Scintillovulva archosargi,
but Unnithan's  assignment of ‘‘(MacCallum, 1913) comb. n.’’ as authorship of M. (S.) archosargi was considered incorrect according to the International Code of Zoological Nomenclature by Kritsky & Bakenhaster.
Microcotyle archosargi was transferred by Caballero & Bravo-Hollis to the genus Paramicrocotyle as Paramicrocotyle archosargi n. comb. Mamaev, in his revision of the family Microcotylidae, suppressed this combination, reassigned the species to the genus Microcotyle and considered Paramicrocotyle a junior subjective synonym of Microcotyle.

Morphology
Microcotyle archosargi has the general morphology of all species of Microcotyle, with a flat body, comprising an anterior part which contains most organs and a posterior part called the haptor. The haptor is symmetrical and bears a number of clamps, arranged as two rows, one on each side. The clamps of the haptor attach the animal to the gill of the fish. There are also two small buccal suckers at the anterior extremity. The digestive organs include an anterior, terminal mouth, a muscular pharynx, and a posterior intestine with two lateral blind-ending branches. Each adult contains male and female reproductive organs. The reproductive organs include an anterior genital atrium, with spines, a dorsal vagina, a single ovary, and a number of testes which are posterior to the ovary.

In 2011, Kritsky and Bakenhaster provided supplementary observations for M. archosargi based on examination of museum specimens and other specimens collected on Archosargus probatocephalus from Florida.
The species was also redescribed by Mendoza-Franco et al. in 2018, from Archosargus rhomboidalis, including a drawing of the genital atrium. These authors also provided the first molecular data (28S ribosomal RNA) for Microcotyle archosargi.

Etymology
The specific epithet Microcotyle archosargi is derived from the generic name of the host species Archosargus probatocephalus.

Hosts and localities

The sheep's head Archosargus probatocephalus (Sparidae) is the type-host of Microcotyle archosargi. The species has been first described from fish caught off New York fishmarket. Although MacCallum collected his fish at the fish market his host record is probably correct. It has also been recorded from the type-host from Florida  and Mexico and from another sparid host, the western Atlantic seabream Archosargus rhomboidalis.

References 

Category:Microcotylidae
Category:Animals described in 1913
Category:Parasites of fish
Category:Fauna of the United States
Category:Fauna of Mexico