Trite

The Trite is an enemy unique to Doom 3. They are small, dog-sized, spider-like demons, characterized by their sharp throaty roar. Their main body resembles an upside-down, human head or Lost Soul, with a cluster of multiple spider-like eyes below the two main ones, and a mouth located up top. Despite their resemblance to spiders, they only have six legs. Trites first appear at the near end of the Alpha Labs Sector 2, in the Lower MFS Control.

Combat characteristics
Trites primarily come in swarms. They attack by leaping at the player from a distance, or by biting at close range.

They tend to surprise the player by crawling out of narrow spaces where the player can't fit, or by dropping from ceilings with the aid of spider thread. Although new Trites often emerge to replace those that are killed, Trite swarms are not infinite.

Trites die differently from other enemies; they curl up into a ball and explode in a splash of green blood. Sometimes the Trite is able to commit suicide by exploding if the player is at an altitude where the Trite is completely unable to harm them. Players that experience this will not have to use any ammunition to kill them, as they would eventually all die off themselves, although the explosion can still do damage to the player.

Tactical analysis
Although individually weak, a large swarm of Trites can be potentially dangerous if the player does not maintain good tactics. While the Shotgun is excellent in dealing with one or two Trites, the weapon's low rate of fire makes it ineffective against a swarm of six or more.

The Machine Gun's high rate of fire and accuracy makes it an excellent weapon against a swarm of Trites. However, larger swarms generally require more than one clip to completely eradicate them. Therefore, make sure your current clip has sufficient ammo as multiple Trites can still attack while you reload. While the Chaingun and the Plasma Gun also has similar advantages, they should be reserved for bigger enemies, as a swarm of Trites is a minimal threat to be using such powerful weapons.

If the player is within a very safe distance from their jumping attacks, even the Pistol can also be effective in taking down a swarm thanks to it's high accuracy, as two shots from the Pistol can finish off an individual Trite.

In Resurrection of Evil, they can be killed instantly with the Grabber. However, it is not recommended to use this weapon when facing a large swarm, due to the slow rate of fire (caused by the cooldown).

Trivia

 * The name "Trite" means two things:
 * A type of jumping spider. (For its obvious arachnid anatomy.)
 * A synonym for the term "overused". (For their large numbers and frequent appearances.)
 * Trite appearances are similar to that of Ticks. This could suggest that they are either related as similar species, or the same species but of different ages (Trites could simply be older Ticks or vice-versa) or different sexes.
 * Doom 3 does not have Spider Masterminds or Arachnotrons, two spider-based enemies. So this kind of creature can be analogous to them.
 * The Trite bears a striking resemblance to one of the monsters in John Carpenter's movie The Thing.
 * The Trite bears a slight resemblance to the Facehugger in the Alien series.