SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '004b017e8119fc79f5f5852742167957467fd3057e9915537ad95554ff21d553' 
  AND token = 'zJZkHo0rblA/bwIY0ZhL3Ru1qhmfUcfkPLfufOGvIeU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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