Ettercap

Ettercaps - the name deriving from an Elvish phrase meaning "venom-head" - are monstrous bipedal arachnids which possess a malign intelligence. The origin of their species is unclear, though it is thought that they have existed for thousands of years; some scholars theorise that they may have originally been created deliberately through magical means. Many Rathi settlements are perennially plagued by ettercap infestations, and violent incursions are not uncommon - though it is rare for ettercaps to attack settlements directly.
Ettercaps share some manner of symbiotic relationship with various species of giant spider, which are often encountered alongside them; ettercaps have been observed to deliberately cultivate herds of giant spiders, feeding and tending to them in a fashion which has led to their name in Katari - "arachnopoimene", meaning "spider-shepherds". Ettercaps are believed to be able to communicate with spiders through some combination of sound and pheremones, though they do not appear to have a language as such.
Ettercaps are typically solitary, and when there is cooperation between individual ettercaps this tends to be on an extremely temporary basis; however their behaviour has been observed to radically change on occasion, associated with the emergence of an "etterqueen". These etterqueens are understood to develop from ettercaps that have been able to consume a large number of fey spirits, in a process which usually takes a number of years; etterqueens are capable of rapidly spawning ettercaps - supposedly by transforming humanoid and fey corpses with mutagenic venom - and of exerting some degree of control over ettercaps which inhabit their territory, making them more cooperative and aggressive. The emergence of an etterqueen is an ecological disaster which can rapidly overtake an area in a matter of weeks or months if not contained.

Basic Information

Genetics and Reproduction

Ettercaps reproduce through parthenogenesis, laying large clutches of eggs in the autumn which will then hatch in the spring. The hatchlings mature within a few weeks of hatching, though few survive to maturity - cannibalism among ettercaps is extremely common, and adult ettercaps do not seem to care particularly strongly about the survival of their offspring.
Ettercaps created by an etterqueen are understood to develop and mature at a much faster rate - potentially a matter of days.

Ecology and Habitats

Ettercaps generally dwell in deep forests and remote parts of the world, and tend to be attracted to areas in which there are an above-average number of Fey. They are known to predate on almost all animals, aside from spiders, but have a particular hunger for the fey, going out of their way to seek out and consume any fey spirits that they come across. Ettercaps do not fit in well with the mundane and spiritual ecosystems that they inhabit, and if unchecked can wreck havoc on an area over the course of months or years, choking their forests with thick cobwebs and devouring any creatures that venture into their territory.