Guyana’s biodiversity extends with discovery of 33 new fish species in remote region

Beneath the mirror-like surface of Guyana’s untamed waters, life teems with newfound wonders, as 33 previously undocumented fish species have been discovered. Among the newly discovered fish are the Potamotrygon boesemani, Microglanis sp., Bryconops sp., Eigenmannia macuxi, Myleus pacu, Cichla ocellaris, Leporinus cf. fasciatus, Metaloricaria nijsseni, Pseudoplatystoma cf. reticulatum, Phractocephalus hemioliopterus, Pseudacanthicus fordii, and Sternopygus astrabes. These findings were highlighted by Senior Conservation Ecologist at the Chicago Field Museum (CFM), Dr Lesley de Souza, during a panel discussion at the Global Biodiversity Alliance Summit on Thursday.
The discoveries came out of a month-long scientific expedition in 2024 to one of the world’s most remote rainforests, located in southeastern Guyana. The mission, carried out by a team of more than 50 experts, including Dr de Souza, was part of a rapid biodiversity inventory aimed at documenting and protecting the region’s biological and cultural heritage.
Dr de Souza, a seasoned conservation biologist and explorer, is known for combining rigorous scientific research with deep respect for cultural traditions and indigenous communities.
“Fishes, which is my love and my area of study on the expedition – we documented 33 new species to science. I’ll say it again: 33 new species to science,” she emphasised. “Most of them are already known locally, and we added 40 new records for Guyana. Because this area had been poorly explored and was new to scientific research, we were able to expand the national fish list significantly. This stingray might even be a new species, so we may be looking at 34.”
Shifting from fins to fur, Dr de Souza also shared findings on Guyana’s rich mammalian life, especially the jaguar.
“This area is incredibly rich in biodiversity. The fish are enormous – I’ve never seen fish this big in my life. Eight of Guyana’s primate species were found in this single corridor. We estimate that about 400 jaguars roam this area. It’s an extremely important place for mammals, and these jaguars are thriving.”
The findings bolster the Government’s ongoing efforts to sustain ecosystem services, strengthen climate resilience and establish replicable models of conservation. Speaking at the same summit, Scientist Engineer at the Indian Space Research Organisation (ISRO), Dr Sudhakar Chintala and Head of Partnerships at the Yale Centre for Biodiversity and Global Change, Dr Claire Hoffmann, explained how data-driven approaches are transforming biodiversity tracking into practical tools for policymakers and practitioners – helping countries meet the global “30 by 30” conservation goal.
Dr de Souza also reported on the comprehensive and collaborative nature of the expedition. “We were able to traverse from the New River to the Essequibo River, learning from the local communities about ecological processes and biodiversity from their perspective. Our team set nets and caught fish for 21 days. We collected plants, compiled bird lists, searched for reptiles and amphibians, reviewed footage from camera traps, and used mist nets for bats. Just as importantly, we learned from local experts who shared their deep knowledge about this landscape.”
She added that the team uncovered evidence of rich human history in the region, including petroglyphs that had never been documented before.
“We found a history of extensive movement across this corridor by Indigenous peoples. These findings provide critical cultural context to our environmental work.” The rapid inventory yielded astounding data in just three weeks, including the identification of an estimated 10 million emergent trees – giant trees towering across the landscape.