The first one is likely a Clytia species hydromedusae - the species are indistinguishable without DNA evaluation during the medusa stage.
www.marinespecies.org
mexico.inaturalist.org
invert-embryo.blogspot.com
Ah, forgot to address this - if you want them to live longer, feed tiny planktonic critters like freshly hatched brine shrimp (Artemia) nauplii, rotifers, copepods, etc.; they feed on these kinds of critters in the wild.Yes, Australia. Thanks for the help. Wonder how long they'll live in the tank - I like them
www.ncbi.nlm.nih.gov
They would be really cool for that - you need to do a special design for the Clytia, though; I suspect you could just put a fine mesh over the nylon retaining filters mentioned in a typical Kriesel tank, but I may be wrong:
www.ncbi.nlm.nih.gov
Ah, yes. It's definitely Pukia Falcata.The first one is likely a Clytia species hydromedusae - the species are indistinguishable without DNA evaluation during the medusa stage.
For image comparisons:
Hydrozoa - The World Hydrozoa Database - Clytia Lamouroux, 1812
Diario de f-sundw · iNaturalist Mexico
Development of the hydrozoan <i>Clytia gregaria</i>
This is Clytia gregaria , formerly known as Phialidium gregarium . The instructor of our Embryology class collected many adult individuals...
I'm fairly certain your specimens are Pukia falcata, as it seems to have the crescent-shaped tentacle bulbs (the two "y-shaped" white parts sticking off the central white white part); this would also make sense given that you're in Australia, where Pukia falcata is reportedly more common than Pleurobrachia (though this wasn't known until relatively recently).
I sent this to my friend who keeps and breeds jellyfish (or at least raises them from very small) and before she had a chance to say anything you had already said everythingThey would be really cool for that - you need to do a special design for the Clytia, though; I suspect you could just put a fine mesh over the nylon retaining filters mentioned in a typical Kriesel tank, but I may be wrong:
"The measurements reported here revealed that the medusae grows to adult size and sexual maturity (about 10 mm in diameter) in less than 2 weeks, a time course suitable for genetic studies. The first few days, i.e. until the juvenile medusae reaches 2.5 mm bell diameter, were found to be critical for successful jellyfish growth for two reasons. Firstly, these small medusae cannot be accommodated in the Kreisel tanks as they pass through the nylon retaining filters. Closed tanks such as bubble-circulating nursery tanks or crystallizing dishes can be used for this stage, though they require additional attention to the water quality with overfeeding being particularly harmful. Alternative systems for the early step of medusa culture could be developed in the future, for instance, to avoid the harmful effect of air bubbles that can damage medusae as they reach larger sizes."*
*Source (same as the "**" source above):
An improved whole life cycle culture protocol for the hydrozoan genetic model Clytia hemisphaerica - PMC
The jellyfish species Clytia hemisphaerica (Cnidaria, Hydrozoa) has emerged as a new experimental model animal in the last decade. Favorable characteristics include a fully transparent body suitable for microscopy, daily gamete production and a ...
