A team of international researchers led by the Complutense University of Madrid (UCM) has discovered a new species of kinorhynch, or mud dragon, in the South Orkney Trench, located in the Antarctic Ocean at a depth of 6,000 meters.
This historic discovery significantly expands knowledge about the biodiversity of these animals in hadal environments, which are areas deeper than 6,000 meters. The newly identified species, named Echionderes australis sp. nov., adds to a very limited group of species known to inhabit such depths.
Kinorhynchs are small animals, measuring between 100 micrometers and 1 millimeter, and are part of the meiofauna, a crucial community for the proper functioning of marine ecosystems.
The study, published in Zoologischer Anzeiger, describes the new species found in a poorly explored environment due to the technical challenges involved. Prior to this discovery, only two kinorhynch species were known from hadal zones, making this new find a 33% increase in the total knowledge of this group in such unique habitats.
Sampling took place in December 2019, where sediment was divided into layers one centimeter thick to a depth of five centimeters, with animals extracted using a flotation method.
The samples were stained with a pigment for animals, and kinorhynchs were separated by hand under a binocular microscope at the University of Southern Denmark. Optical microscopy (LM) and scanning electron microscopy (SEM) were used for identification and analysis, employing interactive keys and specialized literature to describe the new species.
The results of this study have significant implications for the taxonomy of these small invertebrates, as well as for the understanding and conservation of deep marine ecosystems.