Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d2c01ead35dcc463da0e62aac9b52b81cd10ddf81fc5af0ebdba4d8c41cd8ff' 
  AND token = 'OSYzk0NkPlYtMHg/VqNgjHKUBnK02fYoNviAv0a5Vmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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