SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fad0be3fd5f751ebb4d5eae89dcc05ea6f93c71dcf9f2bc160989d60e1f0fd33' 
  AND token = '4TOjuMsCneqXhzZyW2ejbBXNKN2hwPq3gAjjvvYLY8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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