|Average height||Slightly taller than humans|
|Behind the Scenes|
|Universe||Land of the Lost|
|Created by||David Gerrold|
The Sleestak (known by the Pakuni as Sarisataka) are the barbaric descendants of the once prosperous and technologically resourceful people known as the Altrusians. They live in and near the abandoned cities of their ancestors, and act with hostility towards others because of their self-imposed vow to guard these relics. Those who have left the cities to explore other parts of the world have never returned, contributing to the superstitious nature of the species regarding their need to protect their land.
Biology and culture
Physically they are tall, slender humanoids with two claw-like digits on each hand and foot. They have scaly green skin with a yellow abdomen, and a single large spike on the top of their heads. Their mouths are wide, their noses and ears are merely holes and their faces are dominated by huge glossy black eyes. They have a row of spikes on their backs and a stubby pointed tail. The Sleestak skull is the exact same shape and size as their heads, indicating that they might have an exoskeleton.
In the episode "The Hole" it is first revealed that at least some Sleestaks are perfectly capable of speaking English if they wish to, since they have had contact with several humans over the years that passed through "time doorways" to the Land of the Lost. The Sleestak usually don't appear to move their mouths to speak either English or their native language (which is odd considering that the Altrusians usually do move their mouths when they speak), hinting that perhaps their communication may have more to do with telepathy. It is also shown that the Sleestak are born from eggs which are left in the ancient temple of the time portals to be guarded by an allosaurus (the one the Marshalls have named "Big Alice"and which the Sleestak know as Seleema, or "the Protector").
Sometimes, a rare genetic occurrence causes a Sleestak to be born with the memorial knowledge of their distant ancestors, resulting in a highly civilized and knowledgeable individual; but these are treated as freaks by the ignorant and barbaric majority, which have the sagacious Sleestak given as food to some sort of cave creature which they worship as a god. The fact that the intelligent Sleestak describe being born with the knowledge of the universe imprinted in their minds strongly suggests a form of hereditary memory which manifests very rarely in the species.
The Sleestak remain dormant during the cold months, to be awaken again when the flux of volcanic lava rises, increasing the temperature in their cities. The Sleestak eyes cannot stand direct sunlight, to which they are very sensitive. The Altrusian Moth is considered sacred by them, and they believe that if consumed in enough quantity, the insect will give them fertility to increase their numbers in such way to become once again masters of their world. Currently, their population is relatively small, at only seven thousand souls. They are ruled by a council, which Enik, a time-displace Altrusian, regards as ignorant and superstitious. However, the wisdom of their ancestors is preserved in the mystically animated skulls of the Library of Skulls; whom the Sleestak regularly consult for advice.
- In the third season of the show, the Sleestak gain a specific leader who regularly speaks English (or at least is understood by the human characters somehow). They also become more villainous than in the first two seasons; actively seeking ways to destroy the Marshalls rather than attacking just when they got into Sleestak territory.