REP: Streamweed

Streamweeds are a group of in fast-flowing streams living vermiphytes that use their flattened heads to attach onto rocks. While adult forms use excretions that work like cement, their larvae use a sucking mechanism and are able to creep over the rocks to find a suitable place to stay permanently on; one primitive species retains this trait its whole life. While there is some diversity in species depending on the flowing speed of the water they live in, individuals adapt their body shape to the flowing speed, so one species can populate different sections in the stream. The main difference in the streamweed species in one stream is usually the way they reproduce, ecpecially the methods to prevent their gametes and offspring to get washed away.