Not too long ago discovered accordion worm Pararosa vigarae, a brand new genus and species of ribbon worms and a relatively less-known group of invertebrates, has amazed the researchers due to its distinctive means to squash up like an accordion to a staggering one-fifth of its regular physique size. It was found from Ría de Arosa within the Northwest coast of Spain, the place it lurks below rocks within the subtidal zone at a depth of 30 metres (98 ft). Combining morphological knowledge with DNA analysis methods, researchers had been capable of overcome the taxonomical problem of figuring out this worm.

Classification challenges

Based on the research printed in Royal Society Open Science, accordion worms belong to the phylum Nemertea, a bunch of predatory worms that use venom to immobilize their prey. They pose severe challenges for taxonomical research as a result of shortage of exterior morphological options.

Taxonomy is the research of the classification and identification of the dwelling world. Historically, exterior morphological options are thought-about the standards of this research. Nonetheless, Nemerteans have only a few distinctive seen options to depend on. To beat this, scientists tried to think about the inner anatomy as a possible marker, however this course of turned out to be very advanced and inconvenient. Ultimately, this course of grew to become out of date, leading to Nemerteans remaining a lesser-known phylum with at present described 1,350 species.

Genetic Evaluation

The study describes that molecular phylogenetic analyses had been carried out based mostly on partial sequences of 16S rRNA, 18S rRNA, 28S rRNA, cytochrome c oxidase subunit I (COI), and histone H3 gene markers that indicated the newly recognized specimens symbolize a brand new genus and species of heteronemertean within the household Lineidae.

Imaging experiments revealed that the accordion worm contracts its physique to kind common rings which are annular epidermal constrictions that stay seen even when the animal is totally stretched. The variety of rings varies with the scale of the worm—for example, the biggest specimen collected had 60 rings when totally stretched.