An emperor of the Second Klingon Dynasty whose daughter Shenara the Lady Sirella claims as her forebear, a pedigree Jadzia Dax gleefully corrects during her pre-wedding ordeal.
Reclaw was an emperor of the Klingon Empire during its Second Dynasty. The House of Martok's mistress, Sirella, traces her bloodline to his daughter Shenara and recites the descent as part of the chronicle of the women of her house.
The claim is examined in the Deep Space Nine episode You Are Cordially Invited. Required to learn and repeat that chronicle before she may marry Worf, Jadzia Dax does her own research and announces that Sirella's real ancestress was a concubine named Karana who lived outside the imperial stables. The remark helps bring the two women to blows and almost ends the wedding.
Reclaw is never seen and nothing further is said of his reign.