"Stringy moss" has been known in aquaristics for many years under the name Leptodictyum riparium (or Amblystegium riparium). When cultivated submersed it has a strictly upright growth habit, with thin, hardly ramified, irregularly-leafed shoots. However, true Leptodictyum riparium (streamside Leptodictyum moss) looks quite different under the same conditions. This variable species forms rather horizontal submersed shoots with a dense yet flat foliage. In our opinion the "Stringy moss" belongs to Drepanocladus aduncus, not Leptodictyum riparium.
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