6.1.3. Management

In addition to international regulations, it is also protected at the national level, as it is one of the most endangered species of fish fauna at European level. Moreover, since 1993, in the framework of European action programmes, more than 100,000 individuals have been reintroduced in the Valencian region (2500 individuals in the framework of the LIFE04 NAT/ES/000048—aiming at recovering two permanently flooded freshwater pools [102]) and 35,000 specimens were re-introduced in the Ebro delta (Catalonian region; LIFE96 NAT/E/003118 [62]), but at present, the effects of such activities do not appear relevant to preserve the local populations [100].

### *6.2. Valencia letourneuxi (Sauvage, 1880)*

### 6.2.1. Biology and Distribution

*V. letourneuxi* is distributed along the west Greek coast. It is a short-lived species that lives in temperate freshwater basins along the coast and can tolerate a salinity up to 4 [103]. Its original range was a basin in Corfu island (Greece), although it has not been recorded there in recent decades; however, it is widespread from the southern coast of Albania to the Peloponnese. Although it has also disappeared from other aquatic systems due to several causes (water pollution for dairy activities, drying of springs, etc.), the original wide distribution along the coast has prevented the complete extinction of the species [104]. The number of populations is in constant decline and the local density very low (i.e., in the Greek Kalamas river system, *V. letourneuxi* was found only in one site with a relative density <1%, [103]). Its typical habitats are spring streams with deep water and low current speed, with bottoms covered with an adequate bed of vegetation that provides food, protection and substrate for spawning [103].

## 6.2.2. Conservation Status

Beyond pollution and water extraction, the strong competition with *Gambusia holbrooki* is a significant threat [103,104]. Under IUCN assessments, the species is critically endangered and the conservation status is unfavourable/inadequate [105]. In coastal lagoon environments, it has been reported in two Greek sites (Table 3): the Delta Acheloou, Limnothalassa Mesolongiou—Aitolikou, Ekvoles Evinou, Nisoi Echinades, Nisos Petalas and the Limnes Voulkaria Kai Saltini.
