Tortitaenia obscura
Image © Henk Schulp

A cell of Tortitaenia obscura showing a series of chloroplast ridges spiralling around a central core which is slightly reddish coloured at the poles.

Cell dimensions (L x B): ca 110 x 20 µm

Home
Desmid species
- A-G
  - Actinotaenium
    - cucurbita
    - cucurbitinum
    - curtum
    - didymocarpum
    - diplosporum (forma maius)
    - inconspiquum
    - kriegeri
    - mooreanum
    - phymatosporum
    - pinicola
    - riethii
    - rufescens
    - silvae-nigrae
    - subtile
    - turgidum
  - Bambusina
    - brebissonii
  - Closterium
    - acerosum
    - aciculare
    - acutum
    - angustatum
    - attenuatum
    - baillyanum
    - calosporum
    - closterioides
    - cornu
    - costatum
    - cynthia
    - delpontei
    - directum
    - gracile
    - juncidum
    - limneticum
    - lineatum
    - lunula
    - moniliferum
    - navicula
    - nematodes
    - pusillum
    - setaceum
    - striolatum
    - subscoticum
    - turgidum
  - Cosmarium
    - angulare
    - amoenum
    - anceps
    - biretum
    - botrytis
    - brebissonii
    - caelatum
    - cataractarum
    - commissurale
    - connatum
    - conspersum
    - cosmarioides
    - cyclicum
    - denboeri
    - difficile
    - excavatum
    - formosulum
    - granatoides
    - granatum
    - hexalobum
    - holmiense
    - humile
    - impressulum
    - margaritiferum
    - meneghinii
    - microsphinctum
    - monomazum
    - nasutum
    - nymannianum
    - obliquum
    - obsoletum
    - obtusatum
    - ornatum
    - ovale
    - paragranatoides
    - perforatum
    - pericymatium
    - portianum
    - protractum
    - pseudoconnatum
    - pseudoinsigne
    - pseudopyramidatum
    - punctulatum
    - pyramidatum
    - quinarium
    - ralfsii
    - regnellii
    - regnesi
    - reniforme
    - sphyrelatum
    - striolatum
    - subexcavatum
    - subgranatum
    - subprotumidum
    - taxichondriforme
    - tetrachondrum
    - turpinii
    - ungarianum var. subtriplicatum
    - venustum
  - Cosmocladium
  - Cylindrocystis
    - brebissonii
    - gracilis
  - Desmidium
  - Docidium
    - baculum
    - undulatum
  - Euastrum
    - ampullaceum
    - ansatum
    - bidentatum++
    - binale
    - biscrobiculatum
    - coeselii
    - crassum
    - denticulatum
    - dubium
    - elegans
    - gayanum
    - germanicum
    - humerosum
    - insigne
    - insulare
    - lacustre
    - luetkemuelleri
    - oblongum
    - pectinatum
    - pinnatum
    - pseudotuddalense
    - pulchellum
    - ventricosum
    - verrucosum
  - Gonatozygon
- H-R
  - Haplotaenium
    - minutum
    - rectum
  - Heimansia
    - pusilla
    - species
  - Hyalotheca
    - dissiliens
    - mucosa
  - Mesotaenium
  - Micrasterias
    - americana
    - apiculata
    - brachyptera
    - crux-melitensis
    - denticulata
    - fimbriata
    - furcata
    - jenneri
    - oscitans
    - papillifera
    - pinnatifida
    - radiosa
    - rotata
    - thomasiana
    - truncata
  - Netrium
  - Penium
  - Pleurotaenium
    - archeri
    - coronatum
    - ehrenbergii
    - nodulosum
    - simplicissimum
    - trabecula
    - truncatum
  - Roya
    - closterioides
    - obtusa
- S-X
  - Sphaerozosma
  - Spirotaenia
  - Spondylosium
    - ellipticum
    - pulchellum
  - Staurastrum
    - alternans
    - arachne
    - bloklandiae
    - brachiatum
    - brebissonii
    - brevispina
    - chaetoceras
    - cingulum
    - controversum
    - crassangulatum
    - diacanthum
    - dilatatum
    - echinatum
    - elongatum
    - furcatum
    - furcigerum
    - habeebense
    - heimerlianum
    - hirsutum
    - hystrix
    - lapponicum
    - levanderi
    - margaritaceum
    - monticulosum
    - pileolatum
    - pingue
    - polytrichum
    - punctulatum
    - pyramidatum
    - scabrum
    - sexcostatum
    - spongiosum
    - teliferum
    - tetracerum
    - vestitum
  - Staurodesmus
    - convergens
    - cuspidatus
    - dejectus
    - dickiei
    - extensus
    - glaber
    - mucronatus
    - omearae
    - patens
    - pterosporus
    - triangularis
  - Teilingia
    - granulata
  - Tetmemorus
  - Tortitaenia
  - Xanthidium
    - antilopaeum
    - armatum
    - basidentatum
    - bifidum
    - cristatum
    - fascicultum
    - octocorne
    - tenuissimum
    - variabile
Year
Additions

Desmid of the month
August 2004

Tortitaenia obscura

The genus Tortitaenia was rather recently split off from the genus Spirotaenia by Brook (1997, 1998) because of a different chloroplast configuration. Whereas in Spirotaenia the chloroplast is a parietal helical tape, in Tortitaenia the chloroplast consists of an axial core provided with a number of spiralling ridges. Pyrenoids (usually a few, big ones) are situated in the central core and only to be seen in optical section of the cell.

Tortitaenia obscura (synonym: Spirotaenia obscura) is the most common representative of the genus. In the Netherlands it is not rare in slightly acidic, mesotrophic habitats.

References

Brook, A.J., 1997. The proposed establishment of a new desmid genus Polytaenia, previously the sub-genus Polytaenia of the genus Spirotaenia, and a description of a new species, P. luetkemuelleri. — Quekett Journal of Microscopy 38: 7-14.

Brook, A.J., 1998. Tortitaenia nom.nov. pro Polytaenia Brook, a name of a genus of saccoderm desmids — Quekett Journal of Microscopy 38: 146.

Desmid of the month August 2004

Tortitaenia obscura

Desmid of the month
August 2004