Meet the new chief of the South African reefs: The Sodwana Pygmy Pipehorse

Scientists from the Australian Museum and Iziko South African Museum have identified a new species of pygmy pipehorse from subtropical South Africa, Cylix nkosi. The name nkosi is derived from the Nguni or Zulu term for chief due to the crown-like nature of the of the bony protuberance on its head.

This remarkable seahorse new species, found in the subtropical waters off Sodwana Bay, represents the first record of the genus Cylix on the African continent. It is only the second species within the genus, previously known exclusively from New Zealand. This discovery contributes significantly to our understanding of marine biodiversity, particularly within the largely unexplored coral reef systems of South Africa.

Syngnathidae, the family that includes seahorses, pipefish, seadragons, and pygmy pipehorses, now welcomes Cylix nkosi as a key representative. Similar to the closely-related Cylix tupareomanaia, the newly described species has a unique diamond-shaped bony protuberance on its head, along with other distinctive morphological traits. These features allow Cylix nkosi to thrive in coral-rich environments, camouflaging among coral, bryozoans, and algae at depths of 14 to 50 meters.

The discovery of Cylix nkosi was made possible through a combination of advanced fieldwork, micro-CT scanning technology, and genetic analysis. These methods enabled researchers at the Australian Museum to identify the species' unique skeletal features and confirm its evolutionary divergence from related species. Genetic analysis revealed that Cylix nkosi has been genetically isolated for millions of years, providing further insight into the speciation and evolution of cryptic marine species.

Micro computed tomography (μCT) scan of Cylix nkosi, (A) SAMC F041935, female, holotype, 55.5 mm Standard Length, (B) SAIAB 39737, male, paratype, 46.6 mm Standard Length. Image: Graham Short © Graham Short

This finding is noteworthy for its contribution to understanding hidden marine biodiversity in the Western Indian Ocean, particularly South Africa, a region known for its ecological richness. Coral reefs, which provide critical habitats for numerous marine species, are underexplored in terms of smaller, cryptic species like pygmy pipehorses. The identification of Cylix nkosi underscores the importance of continued research and exploration in these fragile ecosystems, where many species remain undiscovered.