Written by Strange Species | 29 August 2010

Happy Face Spider

The Happy Face Spider is only found in Hawaii. In fact it is only found on the islands of Oahu, Molokai, Maui, and Hawaii.

This tiny spider grows to be approximately 5mm. This tiny spider is also unique because it guards it's eggs, and also feeds it's offspring. Scientists are not really sure if the face-like markings serve any type of purpose.

Marking vary from spider to spider, but this one is definitely smiling at us!

The spider is about 5mm long overall.

Certain morphs have a pattern uncannily resembling a smiley face or a grinning clown face on their yellow body. Each spider has a unique pattern, and the patterns differ from island to island. Some lack markings altogether.

On the island of Maui, the happy types seem to follow simple Mendelian inheritance rules, while on other Hawaiian islands the body inheritance patterns seem to be sex-limited. The variation is possibly a kind of camouflage against birds, their only natural enemies of significance, to counteract pattern recognition by predators. As the pattern may change according to what food the spider has eaten (Gillespie, 1989) and as T. grallator is very small, hides during the day, and is thus not a significant prey item for any species of predator, it is more likely that the bizarre variety of patterns serves no significant adaptive purpose at all.

They live beneath the leaves of plants, where they also spin their much reduced webs. The females guard their eggs until they hatch, and catch prey for their young. T. grallator hunts mainly during the evening.