SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14957f8e017e0b3723b734fdf081db283d102c86dd92f37d5dd9fd914ae8a286' 
  AND token = 'J9RWUj9OFvMKDNq0pHAdKJrL78IYIhRVU6odFLjYvwg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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