Haplophryne mollis
Encyclopedia
Leftvent
Leftvents are small, deep-sea lophiiform fish comprising the family Linophrynidae. Twenty-seven species in five genera are represented, distributed throughout tropical to subtropical waters of all oceans....
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Reproduction
Some anglerfishes of the superfamily Ceratioidei employ an unusual mating method. Because individuals are presumably locally rare and encounters doubly so, finding a mate is problematic. When scientists first started capturing ceratioid anglerfish, they noticed that all of the specimens were females. These individuals were a few inches in size and almost all of them had what appeared to be parasites attached to them. It turned out that these "parasites" were the remains of male ceratioids.At birth, male ceratioids are already equipped with extremely well developed olfactory organs
Olfactory system
The olfactory system is the sensory system used for olfaction, or the sense of smell. Most mammals and reptiles have two distinct parts to their olfactory system: a main olfactory system and an accessory olfactory system. The main olfactory system detects volatile, airborne substances, while the...
that detect scents in the water. When it is mature, the male's digestive
Digestive
Digestive may refer to:*Digestion, biological process of metabolism*Digestive biscuit, a British semi-sweet biscuit*Digestif, small beverage at the end of a meal...
system degenerates, making him incapable of feeding independently, which necessitates his quickly finding a female anglerfish to prevent his death. The sensitive olfactory organs help the male to detect the pheromone
Pheromone
A pheromone is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting outside the body of the secreting individual to impact the behavior of the receiving individual...
s that signal the proximity of a female anglerfish. When he finds a female, he bites into her skin, and releases an enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that digests the skin of his mouth and her body, fusing the pair down to the blood-vessel level. The male then atrophies into nothing more than a pair of gonads, which releases sperm
Spermatozoon
A spermatozoon is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote...
in response to hormones in the female's bloodstream indicating egg
Ovum
An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization...
release. This extreme sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
ensures that, when the female is ready to spawn, she has a mate immediately available.
The spawn of the anglerfish of the genus Lophius
Lophius
Members of the genus Lophius, also sometimes called monkfish, goosefish, fishing-frogs, frog-fish, and sea-devils, are well known off the coasts of Europe generally, the grotesque shape of its body and its singular habits having attracted the attention of naturalists of all ages...
consists of a thin sheet of transparent gelatinous material 2 to- wide and 25 to- long. The eggs in this sheet are in a single layer, each in its own little cavity. The spawn is free in the sea. The larvae are free-swimming and have the pelvic fins elongated into filaments. Such an egg sheet is rare in fish.