New research finds three populations of one Cypriot fish species to each be unique!

Newly published work first initiated in 2018 has revealed something very special about the Cyprus killifish, Aphanius fasciatus. The Freshwater Life Project team collaborated with researchers based at The Universita di Pisa, in Italy to analyse specimens of the Cyprus killifish with the aim of determining how closely related they are to their conspecifics from other Mediterranean localities. Additionally, their aim was to also determine how closely related the three known extant Cypriot populations are since the vast distance between each population renders them effectively isolated from each other, an issue that aroused interest from FLP founder Chris Englezou when approaching the Italian team to investigate further.

The completed academic research, authored by Joachim Langeneck, Matteo Di Maggio, Alberto Castelli & Ferruccio Maltagliati of Universita di Pisa, and Chris Englezou, of Freshwater Life Project, was finally published this month in Springer’s Hydrobiologia journal. The genetic analyses produced some interesting results that confirmed suspicions that the Cypriot fish represents a unique line.

The results concluded that the Cyprus killifish does indeed represent a distinctly unique lineage on its phylogenetic tree, but not only that, each of the three Cypriot populations was found to be significantly genetically distinct from each other, and a striking relationship between the level of human impact on habitats and the subsequent reduced level of genetic diversity was identified as the major probably cause, meaning that each population needs to be treated as an independent case of priority for conservation. This conclusion is based not only on the different impacts each population endures at the hands of people, and the different level of protection each habitat receives, but this research has proven these aforementioned factors to directly impact the genetic calibre of the species at a population level; the authors call, in the paper, for immediate recognition of the species as endangered at the local Cypriot level, and for appropriate protection measures to be implemented.

A few pockets of intact habitat remain free of interference, destruction, or degradation by people in all three localities, but with this new research demonstrating a clear relationship between human impacts and low gene diversity, is it time to put some clear measures in place?

So, what does this mean, and what should be done? Well, the results from the research can be broken down and interpreted in the following way:

  1. The uniqueness of the Cypriot variant of Aphanius fasciatus indicates that it requires greater protection measures. Although it is not a separate species, it is unique to Cyprus and not abundant throughout the entire Mediterranean as previously thought.
  2. The genetic uniqueness of each individual population, coupled with the different human impacts they endure, suggests that the habitats of each population should be evaluated for allocation as, or inclusion in protected zones.
  3. The Cypriot variant should be classified as endangered at the national level.
  4. Individuals from the three Cypriot killifish populations should be included in in-situ and ex-situ breeding programs under strict protocols, such as the FLP – R.A.R.E Species program, each population should not be mixed.


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