Medusa Turritopsis rubra (Farquhar, 1895) (Anthomedusae, Oceaniidae) from Devonport, New Zealand.
The size is about 7 mm. This species has until recently been synonymized with T. nutricula McCrady, 1857, a medusa from the western
Atlantic. Morphological and molecular data, however, showed it to be
distinct from the New Zealand Turritopsis rubra.
The oblong objects on the manubrium are planulae, the species is thus larviparous.
Please note that the species depicted is not Turritopsis nutricula but Turritopsis rubra from New Zealand.
The name Turritopsis nutricula has been made popular in the press for its presumed ability to revert its life cycle, viz. being able to return from the medusa stage to the preceding juvenile polyp stage (the immortal jellyfish). Unfortunately, the authors of these experimental studies were not aware that there are several Turritopsis species. Their animals came in fact from the Mediterranean and this population is now considered a distinct species named Turritopsis dohrnii. Turritopsis nutricula is an American species confined to the eastern coast of the North American continent.
The reversal of the life-cycle has only been observed for the Mediterranean T. dohrnii. Turritopsis rubra is unable to revert its life-cycle. Thus using photos of T. rubra in connection with life-cycle reversal would be misleading.