Loligo gigas [now Dosidas gigas] - Humboldt Squid/Jumbo Squid
The Humboldt squid is among the largest of the squid, despite their lifespan of just under one year. Other giant squids have a lifespan estimated to be around five years at a minimum, and don’t reach their maximum size until near the end of their life. One of the major sources of food for Humboldt squid is other Humboldt squids, which is believed to contribute significantly to their fast growth.
All of the suckers of the Humboldt are ringed with sharp, flesh-tearing teeth, and when squid are feeding, they’ve been known to be very aggressive towards scuba divers. Outside of feeding time (generally dusk to dawn), the squid are generally non-aggressive creatures.
Like many squid, the Humboldt has chromatophores in its skin, allowing for rapid color changes. When they feed or are in distress (such as when they’re caught by fishers), they flash bright red. This led to one of their first colloquial names - El diablo rojo - the Red Devil.
Voyage dans l’Amerique Meridionale: Tome Neuvieme. Alcide d’Orbigny, 1847.
A sample of the diversity of life living around hydrothermal vents in the Pacific
Starting from the top and going down:
- A forest of of Giant Tube Worms (Riftia pachyptila)
- bordered by a thicket of their smaller cousins, the Jericho Worms (Tevnia Jerichonana).
- In the right top is an enlarged view of a Pompeii Worm (Alvinella pompejana), one of the most heat-tolerant multicellular animals. Pompeii worms, which live in thin-walled tubular dwellings along the sides of hydrothermal vents, can tolerate temperatures up to 176 degrees Fahrenheit.
- To the left is a Pacific Grenadier (Coryphaenoides acrolepis) a common deep-sea fish often found hunting and scavenging near vents.
- To the right is an Eelpout (Thermarces cerberus), the top predator of the vent ecosystem.
- Below the Jericho Worms is a field of Vent Mussels (Bathymodiolus thermophilus) interspersed with several giant, ivory-white Vesticomid Clams (Calyptogena magnifica)
- At the bottom of the picture is a Blue Mat, a field of tiny tubular dwellings— called lorica— secreted by folliculinid ciliates (Folliculinopsis sp.).
- In the middle of the mat is a magnified view of several of these ciliates with their arm-like peristomal feeding lobes extended.
- Crawling around the field of mussels and worms are several Vent Crabs (Bythograea thermydron) along with a Vent Octopus (Vulcanoctopus hydrothermalis), and a Yeti Crab (Kiwa hirsuta).
- In the lower left corner are several Deep-Sea Stauromedusae (Lucernaria janetae). Stauromedusae are jellyfish that permanently attach themselves to a hard substrate using a short stalk.
- Lastly on the bottom right is a Vent Dandelion (Thermopalia taraxaca), a colonial scavenger related to Portuguese Man-o-wars and other siphonophores.