Sarcosuchus
From Tardis Wiki, the free Doctor Who reference
The Sarcosuchus was a species of ancient crocodile. Vastra referred to it as the "the ancient devourer" and was surprised to find a Sarcosuchus on the European continent. (AUDIO: Spring-Heeled Jack, Family Matters)
Vastra, Jenny Flint, and Strax subdued a Sarcosuchus in River Thames, (AUDIO: Spring-Heeled Jack) which they brought home to 13 Paternoster Row and named Marjorie. After about a week in the newly constructed Siluretum, they made plans to move Marjorie into a stasis chamber until she could be returned to her kind. (AUDIO: Family Matters)
