The Corallovexiidae are a
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
of strictly marine
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 ...
copepods
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have p ...
associated with
corals
Corals are marine invertebrates within the class (biology), class Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important C ...
and, together with members of the family
Asterocheridae
Asterocheridae is a family of copepods
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ...
, dominate their
ecological niche
In ecology, a niche is the match of a species to a specific environmental condition.
Three variants of ecological niche are described by
It describes how an organism or population responds to the distribution of resources and competitors (for ...
in the
West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Greater A ...
; in the
Indo-Pacific
The Indo-Pacific is a vast biogeographic region of Earth.
In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...
, they are replaced by the families
Lichomolgidae and
Xarifiidae.
The family contains two genera and at least 10 species, all described by
Jan Hendrik Stock
Jan, JaN or JAN may refer to:
Acronyms
* Jackson, Mississippi (Amtrak station), US, Amtrak station code JAN
* Jackson-Evers International Airport, Mississippi, US, IATA code
* Jabhat al-Nusra (JaN), a Syrian militant group
* Japanese Article Numb ...
in 1975.
After the 10 known and described species, there were three unknown species found in the
Labrador Sea
The Labrador Sea (French: ''mer du Labrador'', Danish: ''Labradorhavet'') is an arm of the North Atlantic Ocean between the Labrador Peninsula and Greenland. The sea is flanked by continental shelf, continental shelves to the southwest, northwest, ...
and one more found in the Curaçao.
Description
Members of Corallovexiidae are typically semi-transparent or opaque with an off-white color. All members have a dark dot on its head visible through their exoskeleton. Adults are around 2-5mm in length, and exhibit
sexual dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
.
Corallovexiidae females are smaller than their male counterparts and have four pairs of long
pereionites, or lateral horns, as opposed to the males' two. Both males and females have well defined
labrum, but the females have two oral appendages.
Regarding
antennae, the anterior antennae across both sexes are almost identical, but the posterior antennae differ by segmentation; the males' antennae segments are clearly articulated, as opposed to the females', whose segments are less distinct. They only have one pair of
thoracic
The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...
appendages, which are level with the first and second pereionites.
The females' ovaries are on the left and right sides of their
metasome, but the explicit egg sacs have never been found.
Classification
Corallovexiidae contains two genera, Corallonoxia and Corallovexia.
Three unknown species of Corallovexiidae
are not listed here. The Corallovexiidae family's main shared homology is the presence of
pereionite.
Phylogenically, their closest relatives are the
Antheacheridae, which also have large lateral horns, but Coravexiidae lacks the pygmy males present in Antheacheridae. Members of Antheacheridae also do not have as well defined pereionites as Coravexiidae. Another key difference is Antheacheridae's lack of a
caudal ramus
The caudal ramus (plural: ''caudal rami'') is a characteristic feature of primitive crustaceans. Located on the anal somite (telson segment), the caudal ramus is a pair of appendage-like or spine-like protrusions. Specific structures which are ro ...
.
Below is a list of named species:
;''Corallonoxia''
Stock, 1975
;*''
Corallonoxia baki
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallonoxia longicauda
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;''Corallovexia''
Stock, 1975
;*''
Corallovexia brevibrachium
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallovexia dorsospinosa
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallovexia kristenseni
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallovexia longibrachium
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallovexia mediobrachium
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallovexia mixtibrachium
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallovexia similis
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
;*''
Corallovexia ventrospinosa
The Corallovexiidae are a family of strictly marine parasitic copepods associated with corals and, together with members of the family Asterocheridae, dominate their ecological niche in the West Indies; in the Indo-Pacific, they are replaced by ...
''
Stock, 1975
Ecology
The Corallovexiidae described above only infect one polyp and reside there for life.
The number of copepods infecting a single polyp differs among latitude; for example, one study found a
Diploria clivosa polyp from Curaçao containing over 200 copepods (all
C. mediobrachium), while the maximum number found in
Halipteris finmarchica was 3.
Members of Corallovexiidae are endoparasitic, and are usually found in its hosts'
mesoglea
Mesoglea refers to the extracellular matrix found in cnidarians like coral or jellyfish that functions as a hydrostatic skeleton. It is related to but distinct from mesohyl, which generally refers to extracellular material found in sponges.
Descr ...
or
mesentery
The mesentery is an organ that attaches the intestines to the posterior abdominal wall in humans and is formed by the double fold of peritoneum. It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intestines ...
, but the unknown species from the
Labrador Sea
The Labrador Sea (French: ''mer du Labrador'', Danish: ''Labradorhavet'') is an arm of the North Atlantic Ocean between the Labrador Peninsula and Greenland. The sea is flanked by continental shelf, continental shelves to the southwest, northwest, ...
were found in the reproductive organs of their respective corals.
The undescribed Corallovexiidae limited yolk deposition in
H. finmarchica, and when abundant in a colony, lowers its fecundity.
Within
H. finmarchica polyps, males were always found with females, but females were also found living alone.
The sex ratio is highly in favor of the females.
Regarding life history, an intensive study into
Corallovexia longicauda discovered that, during its larval stages it has a very short pelagic span, quickly settling on floating coral larvae after hatching. Due to the small chance that C. longicauda larvae "hits" the floating coral larvae, very few survive. However, if it happens, C. longicauda will populate the growing polyp and create a colony. The colony will end up sustaining itself through self-infestation. Overall, the parasite has minimal effects on its host.
This may or may not apply to other members of the family.
Distribution
Members of Corallovexiidae are found primarily in the waters near
Curaçao
Curaçao ( ; ; pap, Kòrsou, ), officially the Country of Curaçao ( nl, Land Curaçao; pap, Pais Kòrsou), is a Lesser Antilles island country in the southern Caribbean Sea and the Dutch Caribbean region, about north of the Venezuela coast ...
, but unknown species have been found near the coasts of the
Labrador Sea
The Labrador Sea (French: ''mer du Labrador'', Danish: ''Labradorhavet'') is an arm of the North Atlantic Ocean between the Labrador Peninsula and Greenland. The sea is flanked by continental shelf, continental shelves to the southwest, northwest, ...
.
Depending on the species of Corallovexiidae and the species of the host, they can be found anywhere from 0.5 - 40m deep, usually on the ocean floor. The most abundant species of Corallovexiidae is Corallovexia brevibrachium.
The following is a table of preferred depths and common hosts for members of the ''Corallovexiidae'' family:
References
Cyclopoida
Crustacean families
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