Hydrozoa |
Narcomedusae |
Aeginidae
Environment: milieu / climate zone / depth range / distribution range
Ecology
Pelagic. Polar
Antarctic Atlantic: Southern Ocean.
Length at first maturity / Size / Weight / Age
Maturity: Lm ? range ? - ? cm Max length : 9.5 cm WD male/unsexed; (Ref. 7450)
Umbrella transparent and yellowish, disc-shaped, 9.5 cm in diameter, flattened, smooth, with thin but firm mesoglea. Stomach circular, very large, 7.7 cm in diameter including stomach pouches, mouth circular with no pronounced lips; stomach wall thin, yellowish and slightly opaque. Stomach pouches 31, interradial, irregular in shape ranging from rectangular to square, each one with a prominent globular gelatinous protuberance of the umbrellar mesoglea contained within the distal half, giving the general appearance of a rosary chain within the circumference of the umbrella. Each mesogleal protuberance is completely laterally contained within each stomach pouch cavity, without attachments to the lateral walls, and extends into the subumbrella, almost but not completely blocking the distal-most portion of the stomach pouch. Marginal lappets 31 to 32, interradial, larger than stomach pouches, mostly rectangular in shape but a few slightly trapezoidal (minor base centripetal), with distal corners rounded. Peripheral canal system present. Canals uniformally wide, usually wider than the central part of each lappet, and extending vertically along both sides of each peronia. Otoporpae absent. Tentacles 31 (plus one partially developed tentacle base), about 4 to 5 cm in length, rising from roots of variable length embedded between the distal portions of stomach pouches. Peronia 32, fusiform, simple, of irregular length, without cnidocysts, tapering out distally. Gonads not observed. Velum complete, very thin, 0.2 cm wide.
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Members of the order Narcomedusae include L-form hydroids. Life cycle: The zygote develops into planula and later into polyp then into free-swimming medusa.
Fuentes, V. and F. Pagès. 2006 Description of Jubanyella plemmyris gen. nov. et sp. nov. (Cnidaria: Hydrozoa: Narcomedusae) from a specimen stranded off Jubany Antarctic station, with a new diagnostic for the family Aeginidae. Journal of Plankton Research 28(10):959-963. (Ref. 7450)
IUCN Red List Status
(Ref. 130435: Version 2025-1)
CITES status (Ref. 108899)
Not Evaluated
Not Evaluated
Threat to humans
Harmless
Human uses
| FishSource |
Tools
More information
Trophic EcologyFood items (preys)
Diet composition
Food consumption
Predators
Population dynamicsGrowth
Max. ages / sizes
Length-weight rel.
Length-length rel.
Length-frequencies
Mass conversion
Abundance
Life cycleReproductionMaturityFecunditySpawningEggsEgg developmentLarvae PhysiologyOxygen consumption
Human RelatedStamps, coins, misc.
Internet sources
Estimates based on models
Fishing Vulnerability
Low vulnerability (10 of 100).
