stauromedusae;
lucernaria;
16s sequences;
east pacific rise;
hydrothermal vents
Abstract:
Dense populations of "stalked jellyfish" (Stauromedusae) were encountered at two geographically-separated,
deep-sea hydrothermal vent fields located at 7°26'S; and 20°02'S along the East Pacific Rise (EPR). DSV Alvin was utilized
(on dives 3320 and 3334) at the sites to collect numerous stauromedusans, which were immediately frozen (at -70°C) or
preserved in 70% ethanol upon arrival on board the research support vessel (R/V Atlantis). High resolution images were
collected of the organisms in situ. A 530-560-bp region of mitochondrial 16S was amplified, and edited 16S sequences were
aligned, along with sequences from 7 other stauromedusans. Results suggest that the Stauromedusae encountered at 7°26'S,
and 20°02'S are very closely related, if not conspecific. It remains unclear whether or not these Stauromedusae are distinct
from Lucernaria janetae (collected from 8°37'N along the EPR), which was recently described by Collins and Daly (2005).
To date, dense populations of stauromedusans have been encountered at four separate deep-sea hydrothermal vent fields
along the EPR located at the following latitudes: 20°50'N, 8°37'N, 7°26'S and 20°02'S. Many fascinating questions remain
concerning the biogeography and mechanisms of dispersal of these cnidarians between discrete deep-sea hydrothermal
systems.
![[PDF -Full Text]](images/icons/pdf.jpeg){kind=icon}