The Species Black List
Schistura sigillata
Houay Sala Yai stone loach
The Houay Sala Yai stone loach (Schistura sigillata), sought stone loach (Schistura quaesita) and the freckled stone loach (Schistura ephelis) are all known only from the Ngum River.
Status Data Deficient on the IUCN Red List Restriction tier 4, a single named site Class Actinopterygii Realm Indo-Malaysian Locality Ngum River As IUCN records it Schistura sigillata Kottelat, 2000 This species is one of 3,062 in a list of vertebrates the IUCN Red List records as Data Deficient or has never assessed, ranked by how narrowly restricted the published record says they are. The sentence above is the evidence the tier was read from, quoted from Matthew Richardson, Threatened and Recently Extinct Vertebrates of the World (2023).
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Check this species elsewhere: IUCN Red List · GBIF