SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f206cf840da01b971566dba152883cb6a309d31f0ae84f9115d26ff6a9d9e151' 
  AND token = 'GeCltnQJNWd98ktUZUjh7A+xVNSwhZprbN6HQOiRY5M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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