Molecular analyses have demonstrated that all shads endemic to the Aegean, Black and Caspian Sea basins, including Alosa vistonica, share close phylogenetic relationships (Geiger et al. 2014). Their taxonomy may therefore be revised in the future.

The Thracian Shad inhabited a single coastal lake system in northeastern Greece, where it has not been observed since the 1990s despite the existence of a commercial fishery on the lake. No ex situ subpopulations exist. Therefore, it is assessed as Extinct.

This species was endemic to Lake Vistonida (el. Βιστωνίδα) in northeastern Greece.

This species has not been observed in Lake Vistonida since the 1990s.

Lake Vistonida is shallow (mean depth c. two metres) and hypertrophic. It retains an open connection to the sea, but conditions are less saline in the northern portion due to inflowing freshwater rivers. Salinity increases during the summer, when the rivers' discharge is reduced.

The Thracian Shad was pelagic and mainly occupied the upper water column where it probably fed on zooplankton. It is thought to have been non-migratory, with spawning taking place in spring.

Lake Vistonida and the lower reaches of the affluent Kosynthos and Kompsatos rivers suffer from severe hydrological degradation, salinity fluctuations and pollution, driven by the construction of dams and other barriers, excessive water abstraction, agricultural runoff and pumping of raw sewage directly into the water. The reduced discharge of freshwater into the lake and the resultant increase in salinity are considered to be the most important factors which drove the extinction of the Thracian Shad.

Lake Vistonida supports a commercial fishery, the focus of which has shifted from Eurasian Carp (Cyprinus carpio) to mullets (Mugil and Chelon spp.) as the lake has become progressively more brackish.

The Thracian Shad was formerly targeted, but overfishing is not thought to have contributed to its extinction.

This species was included in Annexes II and V of the European Union Habitats Directive (as Alosa spp.) and Revised Annex I of Resolution 6 of the Bern Convention.

Lake Vistonida is located entirely within the boundaries of a National Park which is included in the European Union's Natura 2000 network of protected areas (site GR1130009).