Mouro Lucas D, Zatoń Michał, Fernandes Antonio C S, Waichel Breno L
Programa de Formação de Recursos Humanos, PFRH-PB 240,Universidade Federal de Santa Catarina, 88040-900, Brazil.
Programa de Pós-Graduação em Geologia, Universidade Federal do Rio de Janeiro, 21.941-916, Brazil.
Sci Rep. 2016 Jan 14;6:19215. doi: 10.1038/srep19215.
Caddisflies (Trichoptera) are small, cosmopolitan insects closely related to the Lepidoptera (moths and butterflies). Most caddisflies construct protective cases during their larval development. Although the earliest recognisable caddisflies date back to the early Mesozoic (Early and Middle Triassic), being particularly numerous and diverse during the Late Jurassic and Early Cretaceous, the first records of their larval case constructions are known exclusively from much younger, Early to Middle Jurassic non-marine deposits in the northern hemisphere. Here we present fossils from the Early Permian (Asselian-Sakmarian) marine deposits of Brazil which have strong morphological and compositional similarity to larval cases of caddisflies. If they are, which is very probable, these finds not only push back the fossil record of true caddisflies, but also indicate that their larvae constructed cases at the very beginning of their evolution in marine environments. Since modern caddisflies that construct larval cases in marine environments are only known from eastern Australia and New Zealand, we suggest that this marine ecology may have first evolved in western Gondwana during the Early Permian and later spread across southern Pangea.
毛翅目昆虫与鳞翅目（蛾和蝴蝶）密切相关，是小型世界性昆虫。大多数毛翅目昆虫在幼虫发育期间会构建保护壳。虽然最早可识别的毛翅目昆虫可追溯到中生代早期（早三叠世和中三叠世），在晚侏罗世和早白垩世尤其丰富多样，但它们幼虫构建保护壳的最早记录仅来自北半球更年轻的早侏罗世至中侏罗世非海相沉积。在此，我们展示了来自巴西早二叠世（阿舍尔阶 - 萨克马尔阶）海相沉积的化石，这些化石在形态和成分上与毛翅目昆虫的幼虫保护壳有很强的相似性。如果它们确实是毛翅目昆虫的保护壳（这很有可能），这些发现不仅将真正毛翅目昆虫的化石记录向前推，还表明它们的幼虫在其进化的最初阶段就在海洋环境中构建保护壳。由于目前仅在澳大利亚东部和新西兰发现了在海洋环境中构建幼虫保护壳的现代毛翅目昆虫，我们认为这种海洋生态可能最早在早二叠世的冈瓦纳西部演化，随后传播到泛大陆南部。
