Tintinnophagus acutus

Super Group: 
Alveolata
Phylum: 
Dinophyta
Class: 
Dinophyceae
Sub-Class: 
Peridiniphycidae
Family: 
Duboscquellidae
Genus: 
Tintinnophagus
Species: 
acutus
Authority: 
Coats 2010

Diagnosis

Diagnosis_Genus: Tintinnophagus Coats. Aplastidic ectoparasites feeding on tintinnid ciliates. Trophont lacks flagella, cingulum, and girdle, feeds myzocytotically on host, and possesses a dinokaryon with chromosomes visible in vivo or after staining. Reproduces by palintomic sporogenesis to form numerous biflagellate dinospores with clearly defined cingulum and sulcus. Outer membrane or cyst wall present during palintomy; absent or inconspicuous in trophont. Dinospores with condensed chromosomes.
Diagnosis_Species: Tintinnophagus acutus Coats.Dinospore 13–16 by 9–12 mm with rigid form, sharply pointed episome terminating in a cylindrical ‘‘knob,’’ and a conspicuous yellow to orange cylindrical or crescent-shaped eyespot at base of flagella. Large, ovoid to reneform nucleus positioned posteriorly in cell. Cingulum offset by one-half its width at union with sulcus. Trophont variable in dimension depending on age, with nucleus and nucleolus increasing in size with cell growth.

The SSU–LSU rDNA sequence is deposited as GenBank Accession No. HM483397.

Body_dinospores_length: 13–16 µm
Body_dinospores_wide: 9–12 µm
Body_dinospores_Episome_length: 8–10 µm
Body_dinospores_Hyposome_length 4–6 µm

Pigment: No

Etymology

Species name is the Latin acutus meaning pointed and is used to reflect the sharp convergence of the episome at the cell apex.

Type species

This is the type species of the genus.

Type illustration / Type locality / Type specimen

Type Host: Tintinnopsis cylindrica Daday 1887
Type habitat: The mesohaline portion of Chesapeake Bay, a moderately stratified estuary bordered by the states of Maryland and Virginia, USA.
Type locality: Rhode River, MD, USA (38°53.14'N; 76°32.50'W).
Type material: Hapantotypes, slides with protargol-impregnated T. cylindrica infected by T. acutus, have been deposited
in the International Protozoan Type Slide Collection, National Museum of Natural History, Washington, DC, USA and given the following registration numbers: 1142429 [IZ] and 1142430 [IZ].

Ecology

Substrate_dinospores: planktonic
Substrate_trophont: epizoic (ectoparasite)
Salinity: marine
Salinity: variable
pH: neutral

Life cycle

Generation: <1 month
Reproduction_mode: asexual
Symbiont: horizontal

Feeding behaviour

Parasitism
Myzocytosis

Mode of locomotion

Flagellum_spore:2

Observation site(s)

HOSTS

Displaying 1 - 1 of 1