Trichoptera (caddisflies) are insects with terrestrial adults and aquatic larvae. Although caddisflies spend most of their lives as larvae and pupate in the water, fossils of these stages are rarely found. However, ~100 pupae and uncased larvae were discovered at McGraths Flat, an Australian Miocene Lagerstätte. Many of the fossils are extremely well preserved. In addition to external features that include a spinneret among the mouthparts and claws on the abdominal prolegs, some larvae show silk glands, parts of the gastrointestinal tract, and tracheoles. The pupae are all at the pharate stage; in some, large compound eyes can be seen, and some exhibit male genitalia. Scanning electron microscopy revealed ommatidial structures, such as rhabdoms, corneas, and most remarkably the corneal nanocoating. Two caddisfly morphotypes are preserved at McGraths Flat. The larger morphotype belongs to the suborder Annulipalpia and can be assigned, most probably, to the family Dipseudopsidae. The smaller morphotype closely resembles extant members of the family Hydroptilidae (suborder Spicipalpia). No adult caddisflies or individual wings, no immature pupae, and no larval or pupal cases have been found in the deposit. This unusual fossil record suggests an unstable palaeoenvironment characterized by abrupt change.

中文翻译：

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来自澳大利亚的中新世石蛾：富含铁的沉积物保存了幼虫和蛹的内脏、气管和角膜纳米涂层

毛翅目（石蛾）是具有陆生成虫和水生幼虫的昆虫。尽管石蚕一生的大部分时间都在水中度过幼虫和蛹，但这些阶段的化石很少被发现。然而，在澳大利亚中新世储藏室 McGraths Flat 发现了约 100 只蛹和未装箱的幼虫。许多化石保存得非常完好。除了口器中的喷丝头和腹部前足上的爪子等外部特征外，一些幼虫还显示出丝腺、部分胃肠道和气管。蛹均处于蛹阶段；有些人可以看到大复眼，有些人则表现出男性生殖器。扫描电子显微镜揭示了小眼结构，例如横纹肌、角膜，以及最引人注目的角膜纳米涂层。麦格拉斯平地 (McGraths Flat) 保存有两种石蛾形态类型。较大的形态型属于环须亚目，最有可能属于 Dipseudopsidae 科。较小的形态类型与水翼科（Spicipalpia 亚目）的现存成员非常相似。沉积物中没有发现石蚕成虫或单独的翅膀，没有未成熟的蛹，也没有发现幼虫或蛹的情况。这一不寻常的化石记录表明古环境不稳定，其特征是突然变化。