A Web of Tentacles

Residents of the East African Mangrove Forest often have mysterious ancestries. This is not only because the forest houses organisms originally from all around the Indian Ocean, but also because of its unique inflow from the Dual Mangrove Forest. For example, take these diminutive squids: Idiosepius, the pygmy squids. Among the tiniest squids in the world at only 21 mm (.83 in) in body length, they once lived in mangrove roots and seagrass throughout much of the Indo-Pacific. Besides their adorable appearance, with their small size and stubby tentacles, these animals had two unique features granted them from their distant ancestors. For one, they have a special organ on their undersides that houses a symbiotic bacterium species. This organ, fittingly called the light organ, feeds and shelters the bacteria in return for a constant glow. The organ reflects this light downward, resembling sunlight or moonlight, and thus masking the squid's silhouette against the light filtering down. While the light organ is used by its relatives which swim near coastlines, this feature is overshadowed by a more recent innovation unique to pygmy squids. On the squid's back, there is a very loose patch of skin filled with glands. These glands produce a glue, allowing the loose skin to conform to a surface and adhere the squid there. This organ is imaginatively known as the adhesive organ. Thanks to these, pygmy squids can attach themselves safely to a substrate such as a mangrove root, holding them tight as they hold all their arms out, ready to ambush a small creature.

In the isolation of the East African Mangrove Forest, pygmy squids have produced the gangly squids. Once chubby, they have grown freakishly long and lanky.

Gangly squids glue themselves down in a tangle of mangrove roots to ambush prey, usually small fish or shrimp seeking shelter, just as their pudgy ancestors did. However, gangly squids adopt a tactic completely unique to them. Squids generally hold their arms and tentacles close to their face until about to strike, ambushing the prey with a quick grab that leads to a deadly bite. However, because of how small their prey are compared to them, using all the tentacles like this is simply inefficient. Early gangly squid found that extending the arms and tentacles out in preparation to strike was beneficial even if the target prey animal was far away, for this increased the chance it would get within grabbing range. A natural progression began as the squids started to unfurl earlier, eventually even if no prey was detected. As time passed, these squids splayed their arms wide, stretching the capture behavior to hours long. The modern gangly squid, once having found a hunting spot, unfurls its arms completely and rarely moves, its capture sequence effectively extended to potentially days.

To support their arms instead of holding them tense, gangly squid rest them lightly on nearby roots, spreading them evenly around the mouth. With their arms so positioned, and thanks to their color-changing abilities, gangly squid are nigh invisible in the tangle. Even the slight bulge of their body against the substrate can be obscured with clever use of their light organs. Sitting undetectably in this way, prey items will very often bumble near an arm or tentacle, and upon doing so, they will quickly be snatched up and carried to the mouth to be eaten. This is a stark difference from most squid, which initially nab prey with their two extendible tentacles before wrapping it in arms and bringing it toward the mouth. Gangly squid may still do this if necessary, but their tentacles largely act like their arms, hanging loosely beneath their bodies like leaves stuck to the roots. Thus, all their limbs are used like traps, forming a web: A web of tentacles.

Despite their greatly increased size, at 10 cm (4 in) long in total, they are still small for squids and thus have many predators of their own. Any predator that somehow locates them in the tangle will find that they are very difficult to remove. Their adhesive organ holds them fast against an object, and if a predator grabs one of its tentacles, it will likely break away, allowing the squid to escape. They are most vulnerable when they are out in the open. Early in the year when they emerge to mate, with only tiny fins to propel them and poor vision for a squid, predators will be welcomed to a feast of calamari lasting several days.