Acentropinae

Adults often display a characteristic row of shiny, silvery spots along the trailing edge of the hindwings, with additional metallic spots on forewings and hindwings. Larvae are aquatic and may construct silk cases or possess external gills for respiration. The subfamily is distinguished from other Crambidae by the exclusively aquatic larval stage and associated morphological adaptations.

Exclusively wetlands and aquatic habitats. Larvae inhabit quiet ponds to fast-running streams, living within or upon submerged vegetation. Adults are terrestrial but remain associated with aquatic environments.

Worldwide distribution with approximately 13 species in 6 genera recorded from Europe. Present in Palearctic, Nearctic, and Oriental regions. Species documented from Japan, Papua New Guinea, and North America.

Larvae feed on submerged aquatic vegetation including algae, aquatic plant leaves, and stems. Specific host plants documented include water ferns (Azolla spp.) for Cataclysta lemnata and the invasive aquatic weed Hygrophila polysperma for Synclita obliteralis.

• Microgaster godzilla - parasitoidBraconid wasp that parasitizes aquatic larvae, notably Elophila turbata

Larvae are aquatic throughout development, surviving by trapping air within silk cases or using external gills. Pupation occurs in or near water. Adult females can survive underwater for extended periods, using air trapped within body hairs and scales to deposit eggs on submerged vegetation. Adults are terrestrial and nocturnal.

Larvae construct portable silk cases from plant fragments in some species. When disturbed by parasitoids, larvae may be forced from cases underwater. Adults are active at night; females exhibit underwater oviposition behavior using trapped air for respiration.

Primary consumers in aquatic food webs, serving as hosts for specialized parasitoid wasps. Some species function as biological control agents for invasive aquatic plants.

Some species investigated for biological control of invasive aquatic weeds, particularly Synclita obliteralis against Hygrophila polysperma.

• Other Crambidae subfamiliesAcentropinae distinguished by exclusively aquatic larval stage; other crambids are primarily terrestrial
• Nymphulinae (historical)Now synonymized within Acentropini; modern taxonomy places these genera within Acentropinae

• aquatic
• wetland
• Crambidae
• China-mark moths
• biological control
• parasitoid host

• BugGuide
• Wikipedia
• iNaturalist taxon
• Catalogue of Life
• Insect Treasures from Papua New Guinea | Bug Squad
• Death from below: the first video of a parasitic wasp attacking caterpillar underwater | Blog
• parasitic behavior | Blog
• Waterlily Leafcutter, Synclita obliteralis (Walker) (Insecta: Lepidoptera: Crambidae: Acentropinae)
• A phylogeny of the aquatic moth subfamily Acentropinae (Lepidoptera: Crambidae)
• Microgaster godzilla (Hymenoptera, Braconidae, Microgastrinae), an unusual new species from Japan which dives underwater to parasitize its caterpillar host (Lepidoptera, Crambidae, Acentropinae)
• Water ferns Azolla spp. (Azollaceae) as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758) (Lepidoptera, Crambidae, Acentropinae)
• Supplementary material 2 from: Fernandez-Triana J, Kamino T, Maeto K, Yoshiyasu Y, Hirai N (2020) Microgaster godzilla (Hymenoptera, Braconidae, Microgastrinae), an unusual new species from Japan which dives underwater to parasitize its caterpillar host (Lepidoptera, Crambidae, Acentropinae). Journal of Hymenoptera Research 79: 15-26. https://doi.org/10.3897/jhr.79.56162
• Supplementary material 5 from: Fernandez-Triana J, Kamino T, Maeto K, Yoshiyasu Y, Hirai N (2020) Microgaster godzilla (Hymenoptera, Braconidae, Microgastrinae), an unusual new species from Japan which dives underwater to parasitize its caterpillar host (Lepidoptera, Crambidae, Acentropinae). Journal of Hymenoptera Research 79: 15-26. https://doi.org/10.3897/jhr.79.56162
• Supplementary material 4 from: Fernandez-Triana J, Kamino T, Maeto K, Yoshiyasu Y, Hirai N (2020) Microgaster godzilla (Hymenoptera, Braconidae, Microgastrinae), an unusual new species from Japan which dives underwater to parasitize its caterpillar host (Lepidoptera, Crambidae, Acentropinae). Journal of Hymenoptera Research 79: 15-26. https://doi.org/10.3897/jhr.79.56162
• Figures 8–9 from: Farahpour-Haghani A, Hassanpour M, Alinia F, Nouri-Ganbalani G, Razmjou J, Agassiz D (2017) Water ferns Azolla spp. (Azollaceae) as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758) (Lepidoptera, Crambidae, Acentropinae). Nota Lepidopterologica 40(1): 1-13. https://doi.org/10.3897/nl.40.10062
• Figures 1–2 from: Farahpour-Haghani A, Hassanpour M, Alinia F, Nouri-Ganbalani G, Razmjou J, Agassiz D (2017) Water ferns Azolla spp. (Azollaceae) as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758) (Lepidoptera, Crambidae, Acentropinae). Nota Lepidopterologica 40(1): 1-13. https://doi.org/10.3897/nl.40.10062
• Supplementary material 3 from: Fernandez-Triana J, Kamino T, Maeto K, Yoshiyasu Y, Hirai N (2020) Microgaster godzilla (Hymenoptera, Braconidae, Microgastrinae), an unusual new species from Japan which dives underwater to parasitize its caterpillar host (Lepidoptera, Crambidae, Acentropinae). Journal of Hymenoptera Research 79: 15-26. https://doi.org/10.3897/jhr.79.56162
• Figures 5–7 from: Farahpour-Haghani A, Hassanpour M, Alinia F, Nouri-Ganbalani G, Razmjou J, Agassiz D (2017) Water ferns Azolla spp. (Azollaceae) as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758) (Lepidoptera, Crambidae, Acentropinae). Nota Lepidopterologica 40(1): 1-13. https://doi.org/10.3897/nl.40.10062