Scientists have discovered 10 new species of semi-aquatic freshwater earthworms in river systems in Thailand.
According to a report published in the journal "ZooKeys",
the earthworms in the genus Glyphidrilus occur in a wide range of
natural freshwater habitats which include rice fields, where they might
play an important role in the development of organic farming.
The newly-discovered worms have a rounded body tip, while the end is
square shaped. When twisted, the posterior end, which is normally above
the soil surface, forms U-shaped channels. These are used to allow water
circulation down the burrow.
This is probably an evolutionary adjustment that ensures oxygen
transport to the deeper surface of the worms, while their bodies remain
in the burrows.
Another peculiar feature are the so-called “wings”, or the expanded part
of epidermis near the body tip. The function of the wings is still
unknown to scientists, but it has been suggested that they evolved to
assist breathing in such aquatic habitats.
