Tintinnophagus acutus
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
Mode of locomotion
Reference(s)
Attached phylogeny
Observation site(s)
HOSTS
Association with... | Region origin | Name of site | In reference... |
---|---|---|---|
Tintinnopsis cylindrica | Chesapeake Bay |
Tintinnophagus acutus n. g., n. sp. (Phylum Dinoflagellata), an Ectoparasite of the Ciliate Tintinnopsis cylindrica Daday 1887, and Its Relationship to Duboscquodinium collini Grassé 1952. Journal of Eukaryotic Microbiology 57:468 - 482. doi: 10.1111/j.1550-7408.2010.00504.x (2010) |