Rak-Ush Threadling
Sold by Ves'trak. Awww, aren't her pedipalps adorable? Beast type. This is sold by once you complete his quests. Once you do he will be standing in Azj-Kahet at He sells the pet but it's called "Baleclaw" in his inventory for some reason.
The 
Rak-Ush Threadling is a pet battle companion sold by Ves'trak after completing his quest chain in Azj-Kahet.
Guide awaiting review
Complete Rak-Ush Swarmery quests
Progress through the Rak-Ush Swarmery quest chain, beginning with the Beautification Project quest and concluding with Rak-Ush Under New Management to unlock Ves'trak's vendor inventory.
Purchase from Ves'trak
Find Ves'trak at 74.8, 81.0 in Azj-Kahet and purchase the pet (listed as "Baleclaw" in his inventory) for 
2250 Kej. This unlock is not account-wide, so you must buy it on the character that completed the quests.
Tips
The pet appears under the name 'Baleclaw' in Ves'trak's vendor inventory despite being called Rak-Ush Threadling in your collection.
