From LSWiki

Class: Language Skills
Attribute: Intellect
Pedagogy: Procedural
Practitioner Term: Speaker of Xitid
Hidden Skill
Language Sound: Chittering
Language Difficulty: Very Hard
Language Speed: Very Fast

The ability to speak and comprehend Xitid, the language of the rachnei. 
As with the Sekkcha of the invae, few outside the race speak it, because
of the difficulty of reproducing its sounds with anthropoid vocal apparatus.

Trainers

Wanders: Wikspisk
Association:
Crafty Linguists: Janid Suzak Wanders
Guild:
Quest: