Symbion pandora was an important discovery for scientists in 1995. While it is not considered unusual to discover a new species, it is unusual to find a new phylum. Cycliophora, its designated phylum, was created because the digestive system and reproductive cycle are unique to the animal kingdom. There are still many unknowns concerning S. pandora. Most information on its life cycle and sexual habits are hypothetical.
Symbion pandora is not on vulnerable, threatened, or endangered status. In fact, large populations can be found on a single lobster.
US Federal List: no special status
CITES: no special status
Unknown at this time
Unknown at this time
This species is parasitic on Norweigan lobsters.
Ecosystem Impact: parasite
Species Used as Host:
Symbion pandora attaches itself on the lips of Norwegian lobsters, where it then sweeps food particles into its ciliated, disk-shaped mouth. The digestive system is closely intertwined with the reproductive cycle. A unique feature of the digestive system of S. pandora is that it collapses and becomes larva.
Foraging Behavior: filter-feeding
Symbion pandora can be found on the lips of Norwegian lobsters, Nephrops norvegicus. They are found at depths of 20-40 meters (66-131 feet) from coastal Norway south to the coastline of the Mediterranean region.
Biogeographic Regions: atlantic ocean (Native )
Symbion pandora can be found on the mouth bristles of the Norwegian lobster. It attaches to the lobster with an adhesive disk located on its posterior end. Symbion pandora shares a symbiotic relationship with its host. It recieves easy access to food with out harming or helping the Norwegian lobster. This is called commensalism.
Habitat Regions: saltwater or marine
Aquatic Biomes: coastal
Symbion pandora has a bilateral, sack-like body with no coelom. There are three basic life stages:
Asexual Feeding Stage- At this stage S. pandora is neither male nor female. It has a length of 347 um and a width of 113 um. On the posterior end of the sack-like body is a stalk with an adhesive disk, which attaches itself to the host. On the anterior end is a ciliated funnel (mouth) and an anus.
Male- S. pandora has a length of 84 um and a width of 42 um during this stage. It has no mouth or anus, which signifies the absence of a digestive system. It also has two reproductive organs.
Female- S. pandora is the same size as the male in this stage. It does, however, have a digestive system which collapses and reconstitutes itself as larva.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: sexes alike
Symbion pandora reproduces both sexually and asexually. It reproduces asexually by young budding off from the asexual feeding stage. The sexual cycle begins only during the molting season of the Norwegian lobster, its host. The male attaches itself to a feeding stage that contains a developing female and impregnates her. She escapes from the feeding stage and attaches herself to the host. The larva develops within the female S. pandora She then dies and the larva escapes.
Key Reproductive Features: sexual ; asexual ; fertilization ; ovoviviparous
