It is threatened by habitat loss and considered critically endangered in the International Red List of IUCN, Bern Convention (Appendix III).

Numerous small sharp teeth confined to upper and lower jaws, absent on roof of mouth.

[2] This species is confined to three localities in the Spercheios valley in central Greece: the Aghia Paraskevi Spring, 5 km east of Lamia, and an associated system of drainage channels extending over the areas Diplosoudi and Bourdara, a large system of connected drainage and irrigation channels and natural wells extending over the areas Lykochoria and Kaikia near the village of Moschochori, and a small number of natural wells near the village of Kompotades.

[2] The typical habitat consists of relatively cool spring or slow-running waters (maximum temperature rarely exceeding 20 °C in summer) with rich vegetation.

Specimens inhabit small water bodies and, with its camouflage coloration, exhibit cryptic behavior, remaining among aquatic vegetation during most of the day, and rarely seen in the open areas.

In most areas, this species occurs in sympatry with Pelasgus marathonicus, Alburnoides bipunctatus, Gambusia holbrooki, and Gasterosteus aculeatus.

Stomach content analysis of sympatric species has failed to identify predation on P. hellenicus, but some cases of cannibalism are known.

[2] The type locality (a spring in Kombotades village) is destroyed but small populations remain in nearby wells.

Although individual wells are filled in with earth to increase the cultivation area and the channels are occasionally disturbed for maintenance purposes (excavations, plant cleaning, etc.

[2] Much basic ecological information is needed for this species, including habitat requirements, life history and reproduction behavior, and surveys of existing populations.