SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d6b879110b100eeca9253b03b6f0db5da6612545ab0d7e39a3498e9355b4032' 
  AND token = 'akwRnH9XxlXgIpjM5/DvaiK5NYJ5MiyuTFKdNIqDSfg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}