What is a long necked small antelope?

The most likely answer you're looking for is the Gerenuks. They are also known as the gerenuk, giraffe gazelle, or long-necked gazelle.

Here's why they fit the description:

* Long Neck: Gerenuks have exceptionally long necks, allowing them to reach high into trees and bushes to browse on leaves.

* Small Antelope: They are relatively small antelopes, typically weighing around 35-50 kg.

* Antelope: Gerenuks are classified as antelopes, a diverse group of even-toed ungulates found in Africa and Asia.

However, there are other antelopes with slightly elongated necks, though not as dramatically as the gerenuk.

If you have more specific details about the antelope in question, like its location or any other physical characteristics, it would be easier to identify it.