This week in Lembongan… We were able to find a tiny flatworm drifting in the soft current at the Mangrove dive site. Now normally it is the dive guides with the amazing eyes to spot the tiny little creatures but on this dive, instructor Bryce was lucky to spot this flatworm that was drifting with the current, all curled up in a ball before settling on a bit of coral to open up and hang on. Flatworms are not overly common in Lembongan and when they are spotted it is normally the bigger ones, Around 10cm, but this one that Bryce spotted was around 1 cm long. To protect itself as it drifted in the current, this tiny flatworm curled up into a ball, this also helped disguise itself from hungry passing fish. After a few seconds the flatworm was pushed into some coral and it was able to secure itself long enough that it was able to open up to show the divers it’s true colours.
Over half of all known flatworm species are parasitic, and some do enormous harm to humans and their livestock. Schistosomiasis, caused by one genus of trematodes, is the second-most devastating of all human diseases caused by parasites, surpassed only by malaria. Neurocysticercosis, which arises when larvae of the pork tapeworm Taenia solium penetrate the central nervous system, is the major cause of acquired epilepsy worldwide. The threat of platyhelminth parasites to humans in developed countries is rising because of the popularity of raw or lightly cooked foods, and imports of food from high-risk areas. In less developed countries, people often cannot afford the fuel required to cook food thoroughly, and poorly designed water-supply and irrigation projects increase the dangers presented by poor sanitation and unhygienic farming.
The space between the skin and gut is filled with mesenchyme, a connective tissue made of cells and reinforced by collagen fibers that act as a type of skeleton, providing attachment points for muscles. The mesenchyme contains all the internal organs and allows the passage of oxygen, nutrients and waste products. It consists of two main types of cell: fixed cells, some of which have fluid-filled vacuoles; and stem cells, which can transform into any other type of cell, and are used in regenerating tissues after injury or asexual reproduction.
It was not just small creatures that we have been spotting this week. Our guests have also been lucky to spot some manta rays around at manta bay as well as some friendly turtles coming to say hi as they swim on by.