Meridion circulare var. constrictum (Ralfs) V. H. 1881
Length: 21

 Width: 7

 Costae: 7

 Striae:































Collection 1428a

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Authority information

(Ralfs) V. H., Syn. Diat. Belgique, pl. 51, figs. 14, 15. 1881 (Patrick and Reimer 1966).

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  • For the most part, this taxon is found in the periphyton. Occasionally, specimens from shoreline regions have been found in Lake Michigan (Stoemer and Yang 1969).

  • Synonyms (Patrick and Reimer 1966)
    Meridion constrictum Ralfs, Ann. Mag. Nat. Hist., 12:458, pl. 18, fig. 2. 1843.

  • Ecology
    Like the nominate variety, this taxon prefers flowing, fresh water and is tolerant to small amounts of salt (Patrick and Reimer 1966).

    Size ranges and morphology

  • Length is 12 to 80 micrometers (Patrick and Reimer 1966).
  • Width is 4 to 8 micrometers (Patrick and Reimer 1966).
  • Costae are 3 to 5 in 10 micrometers (Patrick and Reimer 1966).
  • Striae are 15 to 16 per 10 micrometers between costae (Patrick and Reimer 1966).