The semi-aquatic caterpillar of the Nymphula nitidulata, known as the beautiful china-mark (adult shown here), lives and feeds on the branched bur-reed (Sparganium erectum), a wetland plant. The N. nitidulata caterpillar bores into plant stems during early stages, and then ensconces itself in a tube. (Photo via iNaturalist/snsergeevna, CC BY-NC 4.0)