When the reptilian species known as the Race invaded Tosev 3 aka Earth, they came with the purpose of colonizing it. To this end, they bought to Earth many species from Home and other planets of the Empire of the Race. These creatures often found themselves at home, though most perfectly in hot, desert-like conditions like the Sahara or Arabia. These creatures looked a lot like the Race itself, with reptilian scale-like skin and eye-turrets. To humans, though, they could be described as prehistoric animals.
What follows below is an effort to record all species, plant or animal, mentioned in the series. Some creatures are only mentioned rather than fully explained. Such are still given a mention in this article.
An akiss is a very large and dangerous reptilian animal in the mythology of the Race. It is comparable to Earth's dragons. When the Admiral Peary arrived in the Tau Ceti system in 2031, one of several military spacecraft deployed to guard against it was named the Horned Akiss.
The azwaca is a large stock animal native to Home and used by the Race as a foodstuff. Azwaca are also edible to humans. The Colonization Fleet brought azwaca and several other species of livestock to Tosev 3. As Earth plants were not equipped to deal with the extremely economic grazing patterns of these animals, some ecological damage resulted. This in turn led to diplomatic tensions between the Race and the various human powers that shared borders with Lizard-territory.
A common complaint Tosevites reported was that azwaca and related species often ate up all the pasture they came across thoroughly, leaving no more for Tosevite animals. This can be explained as a evolutionary problem- Home was very infertile and therefore animals like azwacas ate anything they came across in Home without being picky. Apparently, the animals brought the same process to Tosev 3.
The beffel is a domestic animal native to Home, kept as pets by the Race. Befflem (plural) are described as having armored hides and possessing stumpy legs despite their agility. They are generally playful and agreeable and make an endearing squeaking noise, but their aggressiveness should not be underestimated: When cornered by another animal, they do quite well for themselves in a fight. Threats include tsiongi and prey include cats and dogs. On Home, there were regulations against letting unleashed befflem run free. On Tosev 3, such regulations were uncommon as befflem were much more inclined to do what they wanted than what the Race wanted them to do.
The eppori was an animal native to Home. By appearances it resembles to "a cross between a zebra and a duckbilled dinosaur" striped in a pattern of gold and dark brown. It was domesticated by the Race early in its history and was used as a riding animal and beast of burden. With the advent of mechanized vehicles, the eppori generally lost its utility in these roles. However, the eppori continued to be used by zisuili farmers and others for attraction.
The krellepem was an aquatic animal native to Home. Their uncanny physiology resembled Earth's extinct trilobites and they were implied to be less evolved. Krellepem are treated as a delicacy by the Race in which special tools are required to break their shells, especially since the Race could not even suck the meat as humans could do. According to Jonathan Yeager krellepem tasted "something like oysters, something like scallops."
Plerkappi was an aquatic animal native to Home and another delicacy by the Race. Sam Yeager considered its flavor to be too strong, which reminded him of clams that had started to go bad.
Sdanli are large, fierce reptilian predators native to Home. In the very ancient history of the Race, petitioners who appeared before emperors (Ssumaz dynasty or otherwise, as this was long before the planet's political unification even by the standards of the Race's history) and did not show the proper respect were thrown to sdanli as punishment. The punishment was later changed to a nonlethal, symbolic one: courtiers in sdanli-skin masks surround the disgraced individuals and mock them.
Avian species with reptilian characteristics flew in the sky of Tau Ceti, one of them being the Sevod. Like many creatures found in Home, they had scales and eye-turrets; unlike birds, sevod and related species had featherless wings. The Sevod was renowned for making musical sounds in the evening and are related to squazeffi.
Ssvapi are a burrowing animal native to Rabotev 2. Throughout the Race's empire, they are notorious for showing extreme aggression and stubbornness in fighting to defend their burrow networks against predators and other intruders. The American defense of Chicago was compared to the territorial defensiveness of such animals by the Conquest Fleet that flew against Tosev 3.
Tsiongi is a domestic animal native to Home and kept as pets by the Race. The plural of tsiongi is 'tsiongyu'. Tsiongyu got along well with both Lizards and Tosevites but were not as friendly or playful as the beffel, an animal with which the tsiongi tended to fight. Domestic tsiongi is used to help herding zisuili unlike its feral cousins who preyed on the meat animals. It is also known for having a reputation in perversity and pride.
Plants that's roots reached deep into the ground was found in desert-like conditions all over Tosev. Like many of other species the Race brought with them, these soon invaded Tosevite deserts.
Zisuili is a large stock animal native to Home and used by the Race as a foodstuff. Zisuili are also edible to humans. The Colonization Fleet brought zisuili and several other species of livestock to Tosev 3. As Earth plants were not equipped to deal with the extremely economic grazing patterns of these animals, some ecological damage resulted. This in turn led to diplomatic tensions between the Race the various human powers.
As said above, the habits of creatures like zisuili and azwaca was very devastating to pastures. The only way to fight off this ecological threat was to kill them and/or eat them, since they were edible to humans. Sam Yeager even pondered an armed border stretching along the American-Race-Mexican border designed for keeping out and/or killing zisuili.