Benghazi – A scientific report published by the British website “Bio Engineering” announced the rediscovery of a rare blind cave shrimp, Typhlocaris lethaea, in the groundwater beneath Benghazi, Libya. This marks the species’ first documented sighting in nearly a century and highlights the hidden biodiversity under the city.
Scientists have confirmed the continued existence of this pale, eyeless shrimp, which was last seen in Leth Cave in 1920. The shrimp was recently found in unexpected locations, despite earlier fears it had gone extinct. Field surveys conducted in 2023 and 2024 recorded the species in two caves in the Kuwayfiya area, expanding its known range by 9 kilometers. This suggests Benghazi’s underground water network is more interconnected and biologically rich than previously believed.
The story of Typhlocaris lethaea began in 1920 when Vito Zanan first observed a decapod crustacean in the cave known locally as “the Large Jakh.” Zanan sent samples to Italian zoologist Bruno Parisi, who initially assigned them to another species. Further study by Scottish zoologist William Thomas Calman at the British Museum revealed, through detailed comparison, that the Libyan specimen was distinct. Parisi formally described Typhlocaris lethaea in 1920, but it virtually disappeared from the scientific record afterward. A modern molecular review failed to find any samples, and the International Union for Conservation of Nature (IUCN) classified the Libyan species as “data deficient,” leaving open the possibility of extinction.
According to the report, all known species in this genus are adapted to total darkness, lacking eyes or body pigmentation, and can be identified by a longitudinal suture behind their antennae. Only four valid Typhlocaris species are known—all exclusive to the Mediterranean basin, with none found in open seas. Typhlocaris lethaea is the only representative from the southern Mediterranean coast, making it endemic to the caves of Benghazi. Its rediscovery is largely credited to cave explorations by Italian researchers in 2007 and 2009.
Researchers from Benghazi University’s Department of Earth Sciences joined the Italian team. They found that the cave is part of a collapse-pit series stretching from northeast to southwest, with two main branches. During an initial exploration in January 2007, several crustaceans—likely Typhlocaris lethaea—were observed. These crustaceans were seen resting on the silty-sandy floor, feeding from saline groundwater, a few meters from a descent platform. The clarity of the water allowed the team to photograph one specimen, providing the first visual evidence in decades.
In 2023, researchers turned their attention to the semi-urban Kuwayfiya area northeast of Benghazi, covering around 835 square kilometers and characterized by karst features. In July 2023, a research team discovered Typhlocaris lethaea on a silty rock surface in Al-Khadim Cave, approximately 15 kilometers northeast of Benghazi. This marked its first recorded sighting in a completely new cave system in over 100 years. Researchers also observed a small, pure white isopod, hinting at an undiscovered community of unpigmented subterranean organisms. Another Typhlocaris lethaea specimen was recorded in a muddy cave floor in Kuwayfiya in October 2023.
On December 7, 2024, researchers from Benghazi University’s zoology and earth science departments confirmed these discoveries. They collected two female shrimp, each measuring 5 centimeters, using a dip net and preserved them in ethanol for further study. The team measured water conditions: an average temperature of 22°C, air temperature of 21°C, pH of 7.67, and salinity of 4.72 parts per thousand. All shrimp sightings occurred in pitch-dark parts of the caves, resembling conditions from Parisi’s original discovery.
The consistency across sites separated by 9 kilometers and nearly a century indicates a real expansion of the species’ known range, from the Bouatni area to Kuwayfiya, just 4 kilometers from the Mediterranean coast. The discovery shows that Typhlocaris lethaea is not restricted to one fragile pool, but may be more common in the Kuwayfiya cave system than previously thought. Researchers say the broader distribution decreases the apparent risk of extinction and underscores hydrological connections. The presence of the same shrimp species in distant caves suggests the underground waterways are interconnected, as the shrimp cannot cross land. The team recommends using cave biology methods, including DNA analysis and hydrogeological techniques, to map and study these hidden channels and their inhabitants.
The report emphasizes that Typhlocaris lethaea is a living indicator of the aquifer’s health. While these shrimp are classified as endangered and listed on the IUCN Red List, the caves where they live remain legally unprotected. Some caves already face threats from human activities, groundwater pumping, and pollution—pressures that could cause rapid habitat loss for this rare species.
Researchers stress the urgent need to involve local stakeholders in protecting these unique cave ecosystems and their biological communities. The greatest threat to a species that survived a century hidden beneath Benghazi may not be disappearance, but the increasing human impact above. Typhlocaris lethaea offers both a warning and a rare second chance to protect Libya’s hidden subterranean heritage.