Chytriodinium parasiticum

Super Group: 
Alveolata
Phylum: 
Dinophyta
Class: 
Dinophyceae
Family: 
Chytriodinidae
Genus: 
Chytriodinium
Species: 
parasiticum
Authority: 
(Dogiel 1906) Chatton 1912
Synonym(s): 
Gymnodinium parasiticum

Diagnosis

Diagnosis_Genus: Ectoparasite of crustacean eggs.
Diagnosis_Species: C. parasiticum. Unknown host egg (Peneid?), but this has 160 µm in diameter, and is surrounded by a mucilagenous layer (60-80 µm large). The stalk, which is the functional hypocone, penetrates the egg of the host and starts boring a tunnel (7-8 µm of dimater) inside the mucilagenous layer. The hyposome then penetrates also inside this tunnel but external cuticle remains outside the host. The whole parasite takes a vermiform shape, penetrates in totality inside the tunnel and directs through the embryo. It takes about 24 hours to reach the embryo. The host can survive to the infection if it can maturate during this stage. Then, the parasite penetrates inside the cytoplasm of its host, the stalk enlarges at its base and forms an ampulla used both as a fixative and a feeding apparatus. Absorption of nutrients correlates with the enlargement of a vacuole that reject the trophont cytoplasm and its nucleus that returned to the external cuticle outside the host. At this time, the tunnel retracts whilst the trophont (containing the nucleus) remains at the exterior, forming a funnel. The whole embryo is digested, visibly by osmotrophy. The rest of the sporogenesis as in other species of Chytriodinium.

Body_spores_length: 9 µm
Body_spores_wide: 6 µm
Body_trophont: 20 µm

Etymology

Chytriodinium: because this parasite has morphological homologies with Chytridium, phycomycete parasites.

Type species

The type species for the genus Chytriodinium roseum.

Type illustration / Type locality / Type specimen

Type host: curstacean eggs

Ecology

Substrate: epizoic
Salinity: marine

Life cycle

Generation: <1 month
Reproduction_mode: asexual
Symbiont: horizontal

Feeding behaviour

Osmotrophy
Parasitism

Mode of locomotion

Flagellum_spore:2

Reference(s)

Beiträge zur Kenntnis des perininen

Dogiel V (1906) Beiträge zur Kenntnis des perininen. Mitt. aus der Zoll. St. zu Neapel XVIII:1-45.

Observation site(s)

HOSTS

Displaying 1 - 2 of 2
Association with... Region origin Name of site In reference...
Copepoda Naples
Dogiel V (1906) Beiträge zur Kenntnis des perininen. Mitt. aus der Zoll. St. zu Neapel XVIII:1-45.
Meganyctiphanes norvegica Villefranche-sur-mer