The organisms were biological creations used by the armed forces, and civilians in the ancient past of the Cobra-La people.
They came in three categories: close quarter combat tools, transportation, and large/small scale, defensive/offensive weaponry.
The first few examples were seen used by Pythons to infiltrate the Terror Drome and incapacitate numerous Cobra personnel.
The next to be seen were seen by the retreating Cobra forces and Roadblock's unit, the latter dismissing them as "redwood toadstools". The 6 Joes under his command would later fall victim to tree shaped versions with extremely strong vines, which are named near the end of the film, while he is saved by Cobra Commander during an escape attempt. The same would also happen to the majority of the team until Big Lob's commandeered Swampfire is shot down, and crashes into them after he leaves a grenade in the chopper.
Other examples include large slug/snake creatures requested by Serpentor during the attack on the civilian security lab, which he referred to as Barabers.
Giant grub and moth like transport aircraft, the latter of which being used to steal the BET along with the above mentioned organisms, were also seen.
The final examples were massive creatures ordered during the Joe's charging of Golobulus's palace to defend it to the death. They included: 1. A bridge resembling a stick insect that the 6 attempted escapees crossed over before encountering the vine trap.
2. A pair of tunnels, which were actually the backs of two six limbed reptiles, with a bulb shaped spider inbetween them.
3. A mantis serving as another bridge, which Sgt. Slaughter beats unconscious after his rifle malfunctioned.
4. Human sized caterpillar like creatures, one that Sgt. Slaughter kicks away, and a second that Lt. Falcon shoots at.
5. Sea cucumber like creatures, one of which Tunnel Rat falls into while backing away from number 1. Three more had Chuckles cornered, though he somehow got away.
6. Was a much larger caterpillar that was killed off screen by General Hawk.
7. A pair of more conventionally shaped spiders which served as the final defensive line at the Palace entrance, which Sgt. Slaughter, Falcon, and Jinx get past while Hawk stalls them, he escaped them somehow as well.
Countless more offscreen were later destroyed when the BET was overloaded by Falcon.