However, those previous studies were made in the field, making it impossible to note more detailed behaviors, like those of Molina (1990) for other species of Brazilian Chelidae, (e.g., Phrynops geofroanus and
Hydromedusa tectifera) observed in captivity.
Our study addresses this issue by examining the fluid interactions in Craspedacusta sowerbyi Lankester 1880, a freshwater, upstream-foraging, rowing
hydromedusa (Hydrozoa: Olindiidae).
In this paper we present the finding of another invasive
hydromedusa, Gonionemus vertens Agassiz, 1862 (Hydrozoa, Limnomedusae), found for the first time in the southern hemisphere.
The lire cycle of the commensal
hydromedusa Eutima sapinhoa n.sp.
Description of a new
hydromedusa from the southwestern Atlantic Ocean, Bougainvillia pagesi sp.
The invasive
hydromedusa Blackfordia virginica (Cnidaria: Black-fordiidae) in southern Brazil, with comments on taxonomy and distribution of the genus Blackfordia.
A second strategy, observed among scyphomedusae and the small
hydromedusa Obelia spp., is to swim using drag-based paddling (Feitl et al., 2009).
These new methods and technologies have allowed scientists to resolve the life cycles of many organisms whose hydroid and
hydromedusa stages were previously thought to be separate species, and to conduct a variety of experimental studies in the laboratory.
The most transparent tissues (at 480 nm) were
hydromedusa mesoglea (66%), followed by Cystosoma (42%), ctenophore mesoglea (41%), siphonophore mesoglea (39%), pelagic tunicares (excluding Pyrosoma) (33%), Sagitta (24%), and the translucent portions of the hydromedusae and ctenophores (24%).