On the track of unknown algae.

The article discusses the concept of cryptic species, which are morphologically similar or identical populations that are reproductively isolated. The use of molecular methods, such as DNA barcoding, has led to the identification of cryptic species in various groups of seaweeds. The article highlights a study on the biodiversity of turf-forming red algae, which revealed the presence of 12 candidate species within the Polysiphonia scopulorum complex. The authors also discuss the challenges of naming cryptic species and the importance of bringing them into a formal taxonomic framework for understanding biodiversity, invasive species, biodiscovery, and marine conservation. [Extracted from the article]