Week Eleven: Hagfish

Common Name: Hagfish, Myxini

Scientific Name: Family Myxinidae

Domain: Eukaryota

Kingdom: Animalia

Phylum: Chordata

Class: Myxini

Order: Myxiniformes

Family: Myxinidae (this post covers all species; a primary genus of this family is genus Myxine.)

Description: I chose to put hagfish on this blog not because they are especially dangerous but because they are some of the most horrendous-looking creatures on this planet. Their bodies are long, fleshy, and whip-like, colored a dark pinkish-brown. Their mouths are jawless leeching suckers ringed by rasps that are similar but differ from teeth. This orifice is ringed by a set of sensory tentacles

Environment: Hagfish live on the seabed and in the twilit depths of the ocean. Here they encounter their already-decomposing food. The habitats they prefer are occur in very cold water, and are usually very dark, though still with some rays of sunlight. Hagfish crowd these environments, as they have a very high population. It is postulated that this is due to a low mortality rate as opposed to a high birth rate, because hagfish do not lay many eggs at a time.

Reproduction & Development: Hagfish hatch from one-inch-long eggs that occur in small numbers. At birth, they are hermaphroditic and for the most part miniature adults. As they develop they will only grow and form a definite sex, which may change over different breeding seasons. This process of foregoing a larval or nymph stage is known as “direct development”.

Nutrition: The main food source of the hagfish is polychaete worms and undersea carrion, especially the corpses of large marine animals which fall from higher levels of the ocean. Swarms of the creatures will latch onto gargantuan cadavers and rend strips of flesh using their tooth-like rasping suckers. Smaller swarms or singular hagfish eat decaying fish in the same way, and the animal is also known to capture and devour small marine invertebrates.