Male Parasitism in Ceratioid Anglerfish

To be driven by impelling odor headlong upon a mate so gigantic, in such immense and forbidding dark- ness, and willfully to eat a hole in her soft side, to feel the gradually increasing transfusion of her blood through one’s veins, to lose everything that marked one as other than a worm, to become a brainless, senseless thing that was a fish—this is sheer fiction, beyond all belief unless we have seen the proof of it.
-William Beebe, 1938

Ceretioid anglerfish represent one of the most remarkable of all animals on this planet. They are found all over the world at depths below 300m. The 160 species represented in the taxon are characterized by alure wielded by the female, called an esca; which houses a community of symbiotic, biolumiscent bacteria; and an amazing mode of reproduction. They exhibit extreme sexual dimorphism, with the females being many times larger than the size of the males. In order to reproduce, the male will bite the side of the female and fuse into her, becoming a parasite. He will be attached to her for as long as she lives, being nourished by her bloodstream. In exchange he will provide sperm to the female upon demand. The female will continue to grow and hunt, in a sense becoming a self-fertilizing hermaphrodite. On this website, we provide an overview of known information regarding these amazing creatures from the perspective of Tinbergen's “4 questions”.

Tinbergen's 4 questions attempt to describe an animal's behavior in its' entirety. They examine the behavior's history (phylogony), development (ontogeny), mode of action (mechanism), and benifit to the organism (adaptation). We will attempt to describe Ceratioid Male Parasitism in this light. Pun intended.


Angler FishAngler Fish 2

Miya (2010)


Neon Angler