7/30/2019 Planothidium lanceolata

1/2

River diatoms: a multiaccess key Jump to a genus

[Home][Taxa][Characters][Environment][Credits][Introduction][Manual][Glossary]

You are in: Home>>Taxa>>Bacillariophyceae>>Planothidium>>Planothidium lanceolata

Planothidium lanceolata (Brb.) Lange-Bert.(1999)

Raphe valve view Brightfield possibly P.frequentissimum

Girdle view phase contrast

Description

Elliptical to elliptic-lanceolate valve outline with broadly rounded or rostrate (occasionallysub-capitate) ends. The valve is flexed in girdle view. Both valves have radiate striaethroughout with a narrow linear or lanceolate axial area. The rapheless valve has a distinctlyone-sided thickening at the centre, which may appear horseshoe shaped, but which lacks adistinct outline. The raphe valve has a central area that is rectangular or butterfly shaped,extending for approximately half to threequarters of the valve width. There is a single plate-like chloroplast, which lies underneath the rapheless valve

Character State

If elliptic or elongate, length 6-40 m

If elliptic or elongate, width 4.5-10 m

If striae resolvable, density 10-15 /10m

Shape in valve view Elliptical or elongated

If elliptic or elongate, transapical symmetry Isopolar

If elliptic or elongate, apical symmetry Isobilateral

Raphe Present

If raphe, position Midline of valve face

Habit

Character State

Colonies Solitary cells

http://openwin%28%27kelly_pla.lan.gv_1%27%2C%27323%27%2C%27230%27%2C%27planothidium%20lanceolata%27%2C%27../images/Kelly_pla.lan.gv_1.jpg','Girdle%20view%20phase%20contrast%20','Image:%20M.G.%20Kelly.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://craticula.ncl.ac.uk/EADiatomKey/html/index.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/taxa.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/Bacillariophyceae.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/Planothidium.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/index.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/taxa.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/charactersets.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/authors.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/introduction.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char125.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char52.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char50.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char7.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char6.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char5.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char99.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char9.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char8.htmlhttp://openwin%28%27kelly_pla.lan.gv_1%27%2C%27323%27%2C%27230%27%2C%27planothidium%20lanceolata%27%2C%27../images/Kelly_pla.lan.gv_1.jpg','Girdle%20view%20phase%20contrast%20','Image:%20M.G.%20Kelly.');http://openwin%28%27000132b%27%2C%27322%27%2C%27207%27%2C%27planothidium%20lanceolata%27%2C%27../images/000132B.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://openwin%28%27000473bb%27%2C%27482%27%2C%27256%27%2C%27planothidium%20lanceolata%27%2C%27../images/000473bb.jpg','','Image:%20ADIAC%20Copyright:%20RBGE.');http://craticula.ncl.ac.uk/EADiatomKey/html/Planothidium.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/Bacillariophyceae.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/taxa.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/index.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/a.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/manual.pdfhttp://craticula.ncl.ac.uk/EADiatomKey/html/introduction.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/authors.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/charactersets.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/taxa.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/index.html

7/30/2019 Planothidium lanceolata

2/2

Attachment By valve face plus mucilage

True Rarely True Unknown

Only by Misinterpretation

Don't confuse with:

Planothidium dubium

Rostrate ends clearly differentiated from main body of valve.

Planothidium frequentissimum

Horseshoe-shaped structure clearly differentiated on valve surface.

Synonyms

Achnantheiopsis lanceolata (Brb). Lange-Bert. 1997Achnanthes lanceolata (Brb.) Grunow in Cleve et Grunow 1880

Achnanthidium lanceolata Brb. ex Ktz. 1849Achnanthidium lanceolatum (Brb. ex. Ktz.) Czarnecki 1987

Taxonomic CommentThe taxonomy and nomenclature of the complex of species around P. lanceolatum is veryconfusing, with Krammer and Lange-Bertalot (1991b) splitting 'Achnanthes lanceolata' intoeight subspecies and distributing a further ten varieties between three of these subspecies.They also place five other species within the "sippenkomplex". Populations of cleanedmaterial often show considerable morphological variation, with many individuals havingcharacteristics intermediate between those for particular 'varieties'. For this reason, acautious approach is adopted here until more studies have been made. See also commentsfor Planothidium delicatulum. For accurate identification, both the raphe and rapheless

valves are needed.

Ecological Information

Common in epilithic biofilms and in epiphytic and episammic habitats across a wide range ofconditions. Experience from UK streams is that it tends to favour nutrient-rich conditions,but there are many records from nutrient-poor environments as well. Bearing in mind thecomments on taxonomic difficulties above, it is possible that the broad ecological rangereflects the 'lumping' of several morphologically-similar species.

Water quality indicators:

S V Comments

Other Indices Saprobic Index (Austria) 2.3 2.3 Tolerant of moderate to heavy organic pollution

Saprobicity (Netherlands) 3 -mesosaprobous

Other Information

pH 4 Alkaliphilous (mainly occurring at pH > 7)

Salinity - UK F Freshwater

Salinity - NL 2 Fresh brackish

Comments to: Diatom Key Development Team

http://craticula.ncl.ac.uk/EADiatomKey/html/Authors.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.html#Salinityhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.html#habitathttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.html#pHhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.html#INFhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.html#vDhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.html#SIhttp://craticula.ncl.ac.uk/EADiatomKey/html/environment.html#INDhttp://craticula.ncl.ac.uk/EADiatomKey/html/taxon13610070.htmlhttp://craticula.ncl.ac.uk/EADiatomKey/html/char128.html