The Evrotas Minnow has a restricted range (extent of occurrence (EOO) 4,252 km², area of occupancy (AOO) c. 260 km²), which meets the thresholds for the Endangered category under Criterion B1 (EOO < 5,000 km²) and Criterion B2 (AOO < 500 km²). It is present at three locations, and the extent and quality of habitat are estimated to be declining.

This species is therefore assessed as Endangered under Criterion B (B1ab(iii)+2ab(iii)).

This species is endemic to the Evrotas (el. Ευρώτας) River system on the Peloponnese Peninsula in southern Greece, including the Vassilopotamos River at its delta, plus the Megalopolis Plain in the upper reaches of the adjacent Alpheios (el. Αλφειός) River.

This species' current population size and trend have not been quantified.

The Evrotas River subpopulation is believed to be relatively stable based on recent studies and conservation actions (see 'Conservation'), but the ecological status of the Alpheios River is understood to be problematic (see 'Threats').

The Evrotas River exhibits a typical Mediterranean flow regime, with hot, dry summers and cool, wet winters leading to temporal dewatering of some reaches during periods of low flow. The extent and longevity of this seasonal drying varies interannually, but in general around 20% of the river's main stem and most of its tributaries are reduced to isolated pools or dry out completely for 5-6 months per year. The highest flows typically occur between February and April, with minimum flows from June to November, but periods of low discharge can be significantly longer in the event of a dry winter.

The river is fed by intermittent streams and permanent karstic springs, of which the latter represent natural refuges for fishes during dry periods.

In the upper and middle sections of the system, the Evrotas Minnow is most abundant in these perennial stretches, which are characterised by relatively cool, flowing water. It inhabits deeper pools and runs with lower water velocities, exhibiting a preference for shallow (< 35 cm depth), marginal areas with submerged vegetation. During periods of water stress it has been observed to move into riffles when the flow rate decreases.

It demonstrates a relatively high level of tolerance to drought conditions, being able to survive in lentic residual pools with low oxygen levels and recolonise desiccated stretches after rewetting.

The Vasilopotamos River is a small, perennial, spring-fed system that was formerly connected to the Evrotas and now runs through the river's delta plain before discharging to the sea.

The upper Alpheios River flows through a wide plain bounded by mountains, and has been heavily-modified to guide its course around the boundaries of a large mining operation (see 'Threats').

The Evrotas Minnow is likely to attain sexual maturity within the first year of life. The annual reproductive period takes place during spring, when the river's discharge and linear connectivity are at their annual peaks.

This species' diet is likely to comprise small aquatic invertebrates, diatoms and algae.

This species' decline has been driven primarily by habitat modification and increased water abstraction during the latter half of the 20^th century.

From the 1950s to the 1990s, river engineering and drainage projects were implemented throughout most of the Evrotas River system in order to control seasonal flooding, irrigate agricultural land and limit human disease transmission. The main river stem has in places been widened and straightened, with riparian vegetation removed in order to control flash floods, and the lower portion runs entirely between dykes. The Vassilopotamos and upper Alpheios rivers have been almost entirely canalised.

More recently, cultivated land has started to encroach on riparian zones, resulting in a loss of natural vegetation, while the irrigation network has been enlarged to include olive and orange groves. Both surface and groundwater are extracted by a number of methods, including irrigation canals, permanent and temporary weirs, pumping stations and private or municipal boreholes (of which there are an estimated 3,500).

Historical records suggest that the Evrotas main stem once flowed perennially, but some stretches of the river and most of its tributaries now dry out on an annual basis. The Evrotas has therefore been referred to as an "artificially intermittent" river, since its naturally variable flow regime has been amplified by human activities.

The intensive exploitation of water has rendered the river susceptible to the increasing frequency and longevity of droughts driven by climate change. Major droughts which extended from 1989-1993 and 2007-2008 led to extensive desiccation throughout the Evrotas catchment, and in 2008 a series of fish kills were reported.

The effects of pollution are also exacerbated during dry periods. A wastewater treatment plant located at the city of Sparta discharges effluents directly into the river, which can cause localised hypoxia during periods of drought. Elsewhere, domestic cesspool waste infiltrates into groundwater or is illegally released into the river itself.

Additional sources of pollution include agro-industrial wastes and diffuse agrochemicals. In particular, the production of orange juice and seasonal activity of olive mills results in large volumes of unprocessed, acidic, nitrogen and phosphorous-rich wastewater being released into the river. Studies and field observations have confirmed that downstream fish and macroinvertebrate communities are largely eliminated during periods of discharge, while extensive eutrophication is apparent in the lower portion of the system.

In 2013, 72% of the Evrotas River system failed to meet the standards of the European Water Framework Directive when native fish communities were included in its ecological assessment.

The non-native Rainbow Trout (Oncorhynchus mykiss) has been observed in the upper Evrotas, and may represent a threat to native fishes through predation. However, reports suggest that it does not successfully reproduce and was either intentionally stocked on an unauthorised basis, or escaped from local aquaculture facilities.

The upper Alpheios River is dominated by the presence of several large open-pit lignite mines (annual production c. 8-9 million tonnes) and an associated power station which have been operating since 1970. Ongoing pollution from these sources is likely to be negatively affecting the resident subpopulation, while the course of the river has been altered several times due to the mines' expansion. Water is also pumped from the karstic aquifer that feeds the river to meet the power station's cooling demands.

This species is not used or traded.

This species is included in Annex II of the European Union Habitats Directive (originally as Phoxinellus spp.), and is protected under Greek national legislation.

The lower part of the Evrotas River including the delta and Vassilopotamos system together form the Ekvoles Evrota protected area. The site is included in the European Union's Natura 2000 network (site code GR2540003), and the Evrotas Minnow is among the target species.

The Evrotas River system has been included in two projects co-funded by the European Union since 2005. The first of these was the LIFE project EnviFriendly (LIFE05 ENV/GR/000245), of which a strategic management plan (SMP) published in 2009 was the major output. The river was then from 2014-2019 one of six river systems covered by the GLOBAQUA project, which investigated the effects of water scarcity on aquatic ecosystems and supported further development of the SMP as well as a series of scientific publications.

Some objectives listed in the SMP include the adoption of organic and other sustainable farming practices, improved management of drainage canals, reduction in fertiliser use, restoration of riparian vegetation and the river's bed, establishment of ecological flows below points of water abstraction, enhanced wastewater treatment facilities and extension of existing protected areas. Among these, an organic farming system has already been introduced, while several others are in the process of implementation.

At the species level, a number of studies investigating the Evrotas Minnow's life history, habitat requirements and response to the ongoing threats have been published since the 2010s. Initial efforts to establish potential sites for a translocated subpopulation in order to safeguard the species have also been carried out.

No conservation management is currently being carried out in the upper Alpheios River.