SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f34533fff940d18d32ceda4d2b44576b31cf3e30ef9f84fe926262220810560' 
  AND token = '3+LWzyxPfOXWQhSyvJH2/BHExZFVUI8LhufXlYsCk2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}