Scientists discover a new species of leeches in Antarctica: photo

Ukrainian zoologists Andriy and Serhiy Utevsky discovered a new species of Antarctic leech, and also found that millions of years ago its ancestors migrated first from the Antarctic to the Arctic and then back to the Antarctic.

They did this work in collaboration with foreign colleagues Aleksander Belecki and Joanna Cichocka from Poland, Mario Santoro from Italy, and Peter Trontel from Slovenia, according to a Facebook post by the National Antarctic Science Center. SSPDaily learned more about it.

Together, the scientists studied the spread of fish parasites - piscicolid leeches. Having discovered a new species, the zoologists carefully studied its external and internal structure, as well as nuclear and mitochondrial genes.

"It turned out that the new leech belongs to a group called platybdelinae. They are common in the Arctic and adjacent waters of the Atlantic and Pacific. It's the same as finding a polar bear in the Antarctic!" said Serhiy Utevsky.

Next, the scientists began to study how such an extraordinary geographical distribution could have occurred, since most animals live exclusively in either the Northern or Southern Hemisphere. After conducting a series of studies, the scientists established incredible facts.

"Phylogenetic analysis and reconstruction of the ancestral habitats showed that fish leeches originated in the seas around the Antarctic, then they spread across the world oceans, reached the Arctic and penetrated the freshwater bodies of the Northern Hemisphere. However, later the ancestor of our species returned from the north to the homeland of the ancestors of the entire family of fish leeches in the Antarctic," the scientists explained.

The molecular clock showed that the new species separated from its northern relatives about 1.76 million years ago during the Pleistocene, when the Earth's surface underwent significant cooling. It was during this era that it was able to cross the tropics.

"We have assigned the new species to a new genus called Austroplatybdellina, which means 'southern platybdellina' in Latin, because this Antarctic leech belongs to the predominantly northern group of platybdellines. The evolutionary history of the new species reminds us of the parable of the prodigal son who left his father and wandered in distant lands, just like the platybdelina leeches in the northern seas. Eventually, one of them returned to his southern ancestral home. The Latin word for "prodigal" is "prodiga". Thus, the full official name of the new species described by us is Austroplatybdellina prodiga," said Serhiy Utevsky.

We remind you that the Utevsky brothers are well-known researchers of polar regions from Kharkiv (V. N. Karazin Kharkiv National University). They have been studying leeches from different regions for many years: Serhii - Arctic, and Andrii - Antarctic (he was a winterer of the 8th UAE and a member of numerous seasonal expeditions to the Akademik Vernadsky station). To date, they have discovered 19 species of animals new to science.