New Worm Species Found in Poland's Reclaimed Lands

Two new species of Achaeta, a type of small, soil-dwelling worm, have been discovered in southern Poland. These worms are unique because they don't have chaetae, which are tiny bristles found in other annelids. Scientists found these worms in areas that were once mined or burned. They studied both living and preserved specimens and even looked at their DNA to understand them better. The first species, Achaeta florens, was found in a former mining site. It has special glands and a unique clitellum, which is like a collar around the worm. This species is hard to tell apart from another called Achaeta nurmineni, because not much is known about it. The second species, Achaeta gemmata, was found in large numbers at a site that had been burned. It has special, gem-like bumps on its sides. These bumps are actually enlarged gland cells. This species doesn't have an oesophageal appendage and its clitellum is closed on top. It looks similar to another worm found at the same site, but scientists can tell them apart using both sexual and non-sexual features. When scientists compared the DNA of these new species to others, they found that Achaeta florens is similar to a worm from Sweden that was wrongly identified. The two new species are quite different from other Achaeta species, with a DNA difference of 20% between them and 16-26% with other species.