No, it is not. The widely used laboratory Hydra strain previously called Hydra attenuata is actually Hydra vulgaris. The history of the species name attenuata is quite convoluted and is described in detail by Dr. Richard Campbell in a paper published in 1989 (Campbell, 1989). At the Hydra meeting in Günzburg, Germany in 1989, Campbell presented a poster on Hydra taxonomy in which he showed that the brown Hydra being used in many laboratories at the time and called Hydra attenuata should be called Hydra vulgaris. Attendees at the meeting were split with regard to replacing attenuata with vulgaris or continuing to use attenuata. The decision to replace attenuata with vulgaris was made when Dr. Leo Buss of Yale University spoke up at the meeting, saying something along the lines of “You have no choice, it’s Hydra vulgaris.” You may notice that most papers reporting results of toxicological studies using Hydra still incorrectly refer to their test strain as Hydra attenuata, even though it is clearly Hydra vulgaris.

REFERENCE

Campbell, R.D. (1989). Taxonomy of the European Hydra (Cnidaria: Hydrozoa): a re-examination of its history with emphasis on the species H. vulgaris Pallas, H. attenuata Pallas and H. circumcincta Schulze. Zool. J. Linnean Soc. 95, 219-244.