The Malta National Aquarium has recently posted on its social media pages to introduce us to the fascinating world of upside-down jellyfish!

Despite their name, these intriguing creatures spend most of their time resting on the seafloor, but occasionally, lucky observers may catch them gracefully swimming.

In fact, according to our research, in 2018 there was a bloom of several hundreds of these upside-down jellyfish, also known as Cassiopea Andromeda, in Maltese waters. Up until that year, they had not been seen for nine whole years.

Their unique upside-down posture serves a vital purpose; it facilitates a symbiotic relationship with algae living in their oral arms. These algae rely on sunlight for photosynthesis, so by positioning themselves upside down, the jellyfish expose them to ample sunlight. In return, the jellyfish receive nutrients primarily from the photosynthesis process, supplementing their diet of small prey.

It's a remarkable example of nature's interconnectedness, where even the simplest organisms work together to thrive in their underwater habitat.

If you're fortunate enough to spot one, take a moment to marvel at the beauty of these upside-down jellyfish. But be careful, because even though this species is not dangerous to humans, they will still inflict a very mild sting.

Have you ever spotted an upside-down jellyfish before?