SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2ff335df210a59d60812fcab6081ae5d19f1e5763e4b84e254337af77a56eea' 
  AND token = 'oqWdt7HO2SZw0RRWu6v52LEhyB7AxrZGkEJVfuoMvHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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