Pararosa vigarae, a newly discovered marine tapeworm species found off the coast of Galicia, Spain, adds vital insight into marine biodiversity and highlights the importance of genetic analysis in species identification.

Unveiling Pararosa vigarae: A Breakthrough in Marine Biodiversity


In a landmark discovery, marine scientists have identified a previously unknown species of tapeworm—Pararosa vigarae—living in the coastal waters of Galicia, Spain. Dubbed the “accordion worm” due to its ability to contract into ring-shaped folds resembling an accordion, this new species was confirmed through a meticulous combination of physical observation and molecular genetic analysis. The finding, published in the Royal Society Open Science journal on May 7, 2025, underscores the transformative role of DNA sequencing in modern taxonomy and the continued importance of exploring under-studied marine habitats.

Pararosa vigarae: The Accordion Worm of Galicia


Named Pararosa vigarae, the new tapeworm species inhabits the estuarine waters of the Ría de Arosa in Galicia. Its most remarkable feature—its body’s accordion-like folding structure—sets it apart from previously known species. These ring-shaped contractions not only lend it its nickname but also signal a unique adaptation among the Nemertea group, a phylum known for its ribbon-like marine worms.

Through advanced genetic analysis paired with detailed morphological examination, researchers confirmed that Pararosa vigarae is a distinct species. Its discovery expands the global inventory of tapeworm biodiversity and reveals the untapped potential of Spain’s northern coastal waters as a haven for undocumented marine life.

Redefining Species Discovery Through Genetics


The identification of Pararosa vigarae highlights the limitations of traditional classification methods, which relied heavily on external anatomy. Tapeworms, with their simple and often indistinct outer features, have long been difficult to categorize with certainty. By integrating molecular genetic techniques, scientists can now analyze DNA sequences to uncover subtle but definitive differences between species.

This approach, now a standard in parasitology and marine taxonomy, has revolutionized how new species like Pararosa vigarae are identified. Genetic markers provide accuracy and efficiency, making the discovery of hidden marine biodiversity far more attainable.

Galicia’s Underexplored Waters Yield Scientific Gold


The sub-tidal zones of Galicia, particularly the Ría de Arosa, have seen limited scientific attention in terms of stripworm diversity. Most marine biological research in Europe has traditionally focused on other coastal regions, leaving parts of Spain’s northwestern seaboard largely unexplored. This gap makes discoveries like Pararosa vigarae particularly valuable, not just as new entries in scientific catalogues, but as indicators of the ecological richness and resilience of these ecosystems.

Marine scientists used SCUBA diving to collect live specimens from this under-investigated habitat. High-resolution imaging combined with DNA analysis provided robust evidence for the worm's uniqueness. This successful model of fieldwork exemplifies how collaboration between marine biologists and local diving communities can unlock scientific insights in difficult-to-access marine zones.

Beyond Discovery: The Urgency of Biodiversity Protection

Understanding What Lies Beneath

The discovery of Pararosa vigarae comes at a time when marine ecosystems face mounting threats from pollution, overfishing, and climate change. With only 1,350 species of tapeworms currently identified and an estimated 1,400 more yet to be discovered, the findings underscore an urgent need to accelerate exploration and conservation efforts.

This study demonstrates how combining classical taxonomic skills with cutting-edge science not only enriches biological records but also sharpens our understanding of fragile ecosystems. The presence of such an unusual species in Galicia further emphasizes the importance of preserving biodiversity hotspots that remain hidden beneath the waves.

 A New Chapter in Marine Exploration

Pararosa vigarae Sheds Light on Oceanic Mysteries

The unveiling of Pararosa vigarae represents more than the discovery of a new species; it marks a triumph in modern marine science. It showcases the power of innovation, the value of collaboration, and the enduring mystery of our oceans. As scientists continue to explore the depths, each new species found—like the accordion-shaped Pararosa vigarae—brings us closer to understanding and safeguarding the rich, complex tapestry of life that lies beneath the sea’s surface.