A brooding marine worm found in Antarctica

Nemerteans are a group of invertebrates mainly found in marine waters. The research group led by Professor Àvila, who coordinates the project Actiquim developed in Antarctica, discovered a new species of nemerteans, Antarctonemertes riesgoae, which has a reproductive strategy unique in this group: it broods like hens.

In marine Antarctic waters, UB experts found some 2-3 cm long cocoons brooded by female nemerteans. During reproduction, females secrete a very dense mucous through the body wall; it solidifies when getting in touch with marine water until creating then an elastic layer. Once the cocoon is created, females lay eggs on it. Unexpectedly, they act in a non-passive way: when cocoons are disturbed, females show a defensive behavior and go out through cocoons' openings.

Egg brooding increases reproductive success

Generally, nemerteans, like other living beings, lay eggs but later they do not brood them. To date, only two nemertean species were known to brood eggs. According to the research group, this exceptional behavior is due to extreme Antarctic weather conditions. The strategy may result in an increase of reproductive success for many Antarctic species which can only reproduce themselves during the polar summer.

Actiquim project

It is important to remember that the group led by Professor Conxita Àvila participated in the discovery of a new species of Osedax, a bone-eating marine invertebrate, named Osedax deceptionensis. This species, together with the so-called Osedax antarcticus, are the two first species of this type of marine worm found in Antarctica. Professor Conxita Àvila has coordinated the project Actiquim (I and II) since its setting up in 2007. The project is funded by the former Spanish Ministry of Science and Innovation. Its main objective is to analyze chemical ecology in marine invertebrates which inhabit Antarctic waters.