New freshwater parasite species Paradiplozoon jordaanae named after CapeNature ecologist Dr Martine Jordaan

In a rare glimpse into the largely hidden world of freshwater parasites, researchers have described a new species of fish ectoparasitic flatworm and named it Paradiplozoon jordaanae in honour of CapeNature Fauna Ecologist Dr Martine Jordaan.

The naming recognises Dr Jordaan’s deep knowledge of the aquatic life of the Cape Fold Ecoregion—an area known for its remarkable freshwater endemism and sensitive river ecosystems. CapeNature says her continuous commitment to studying local fish and their parasitofauna has made a lasting impact on freshwater biodiversity research and conservation in the Western Cape.

A new species tied to threatened local fish

Paradiplozoon jordaanae was identified through studies of parasites taken from the gills of two near-threatened freshwater fish species endemic to the region: the Clanwilliam sawfin (Cheilobarbus serra) and the Clanwilliam redfin (Sedercypris calidus). Specimens were collected from the Matjies River and the Rondegat River within the Cape Fold Ecoregion.

These fish are not only important conservation subjects in their own right; they also serve as ecological “hosts” that support specialised parasite communities. In this case, the newly described parasite was first detected in the Rondegat River in the Cederberg—highlighting the value of careful fieldwork in remote catchments where biodiversity can remain scientifically underexplored.

CapeNature CEO links the discovery to collaboration

CapeNature CEO Dr Ashley Naidoo said the species’ formal naming underlines how collaboration can accelerate conservation science in the Western Cape.

“Having a species named after Dr Jordaan is significant recognition,” CapeNature notes, adding that the achievement reflects both her personal contribution and the wider freshwater biodiversity work underway in the Cape Fold Ecoregion. The organisation also points to the practical reality that effective conservation outcomes often depend on partnerships—sometimes formal, sometimes built through long-term informal cooperation—between conservation practitioners and academic researchers.

How an unusual parasite led to a long research pathway

The discovery did not happen overnight. It emerged from a collaboration that began nearly six years ago when Dr Jordaan encountered an unusual fish parasite during fieldwork on redfin fish.

In this instance, the parasite was identified as a fish ectoparasitic flatworm. Researchers say this parasite type had not been observed in rivers of the Cape ecoregion for many years, making the finding especially noteworthy. What followed was deeper cooperation between Dr Jordaan and scientists at North-West University (NWU), particularly researchers affiliated with the Water Research Group.

The partnership combined two essential elements. On the one hand, Dr Jordaan brought field-based conservation expertise—supporting access to freshwater systems and assisting with extensive fish surveys. On the other, NWU researchers conducted specialist parasite identification and genetic analysis in laboratory settings. Together, these approaches allowed the team to confirm the parasite as a new species rather than a previously known form.

From river sampling to microscope-based discovery

CapeNature describes how Dr Jordaan supported broader sampling across Western Cape river systems, contributing to investigations into parasite biodiversity, fish health, and species conservation. This kind of work is labour-intensive: it requires repeated field visits, careful handling of fish and parasites, and collaboration across disciplines to interpret what the findings mean for ecosystem health.

Dr Jordaan reflected on the broader lesson behind the discovery: “For me, the specialness of it is seeing how your little bit feeds into something bigger. It really shows the value of collaboration and what can be achieved when people with different expertise work towards the same goal.”

She also stressed that conservation science often needs time-consuming specialist work that may not fit neatly into every applied conservation schedule. In describing fish parasites, she pointed out that much of the relevant evidence only becomes visible under magnification.

“In fish parasites, there is this whole undiscovered world that you can basically only access under a microscope. And as conservation is such an applied and practical field, we do not always have time to investigate these specialist disciplines,” Dr Jordaan said.

Why parasites deserve conservation attention

Although the word “parasite” can sound alarming, CapeNature highlights an important conservation nuance: not all parasites are harmful. Non-pathogenic parasites that do not pose risks to humans or their animals can still be a legitimate part of biodiversity—particularly in freshwater systems where ecological relationships are often tightly connected and highly local.

The team’s work is also described as contributing to wider discussions on parasites’ ecological roles, including how they can be part of a balanced biodiversity system. Rather than treating all parasites as threats, the discovery supports a more science-based view: understanding which parasites exist, where they occur, and how they relate to host species and environmental conditions can strengthen overall ecosystem understanding.

In practical terms, a better grasp of parasitofauna can inform fish health monitoring and improve conservation planning for endemic species already under pressure. Near-threatened endemics like the Clanwilliam sawfin and Clanwilliam redfin depend on intact river habitats—and parasite biodiversity can be another indicator of ecological stability.

Dr Martine Jordaan: a career built on aquatic conservation science

CapeNature profiles Dr Martine Jordaan as an aquatic biologist with a background in environmental toxicology and conservation science. She has worked for CapeNature since 2010, focusing on indigenous freshwater fish and aquatic ecosystem conservation through integrated catchment management in the Cape Fold Ecoregion.

Beyond CapeNature, Dr Jordaan serves as an honorary research associate at the South African Institute for Aquatic Biodiversity (SAIAB) and the Centre for Invasion Biology (CIB). She has authored and co-authored more than 20 peer-reviewed papers and book chapters, including research touching on invasion biology and how invasive species interact with environmental variables and pollutants.

A constructive takeaway for conservation in the Western Cape

This discovery offers a timely reminder that conserving ecosystems requires more than protecting visible wildlife. It also means funding and valuing the scientific capacity to study less obvious biodiversity layers—such as parasites—and connecting that knowledge to freshwater conservation goals.

By naming Paradiplozoon jordaanae after Dr Jordaan, the scientific community is effectively recognising that fieldwork and lab analysis are inseparable in modern biodiversity science. The discovery also strengthens the case for continued investment in long-term monitoring, particularly in river systems like the Rondegat and Matjies—where unique life cycles still depend on healthy habitats.