Larvae of lacewings (Neuroptera) are known to be fierce predators. According to the morphology of fossil forms thisseems to have been the case already in the Early Cretaceous. While being predators, lacewing larvae are also food itemsfor other organisms. Here we report two pieces of amber from Myanmar providing instances of such cases. In one amberpiece several isolated stylets of lacewing larvae are preserved closely associated together. The most likely interpretationis that a predator preying on lacewing larvae has regurgitated or defecated these non-digestible pieces, yet the identityof the predator remains unclear. The other amber piece preserves a larva resembling modern day larvae of split-footedlacewings (Nymphidae). The larva has projections on its trunk, allowing it to wear a camouflaging cloak. In the headregion, a mite (Acari) is attached to the larva; more precisely, the entire anterior body region of the mite is apparentlyinserted into the lacewing larva. The mite is smaller than the larva. It is known from the modern fauna that stage 1 larvaeof Ascalaphidae can be attacked also by rather small predators, such as ants. The mite can therefore well be interpretedas a true predator instead of a parasite, especially considering the unusual mode of attachment. We briefly review interactionsof lacewing larvae with other organisms represented in amber from Myanmar and add two new pieces to thepuzzle of reconstructing the trophic interactions in the 100-million-year old amber forest.

Lacewing larvae (Neuroptera) are known to be fierce predators which are morphologically highly specialised for a raptorial lifestyle. Mandibular-maxillary stylets are characteristic for all larvae of this group; these stylets can be extraordinarily massive. Despite these distinct sucking-piercing stylets, also other extreme features occur in some ingroups, such as an extremely elongated neck. In larvae of thread-winged lacewings (Crocinae) the neck can reach up to about one third of the body length; they are also called ‘long-necked antlions’. Even though the larvae of living neuropteran species show a variety of conspicuous morphologies today, indeed 100 million years ago, in the Cretaceous, Neuroptera seems to have had an even more “experimental phase”. Several larval specimens are known so far especially in Myanmar, Spanish and Lebanese amber from the Cretaceous with unique and unusual character combinations not found in any group living today. We describe here ten new fossil findings of one of these types of larvae with elongated head capsule in Myanmar amber, previously only known from a single specimen. We compared the head shapes of the new specimens with those of 190 specimens of other lacewing larvae and discuss further implications of our findings, especially making functional comparisons with long-necked antlions.

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Lacewings (Neuroptera) have predatory larvae with highly specialised mouthparts. Larvae of many groups within Neuroptera are well represented as fossils preserved in ambers; however, larvae of some groups are less often reported in the literature. Here we report such a rare case, a larva of the group Hemerobiidae, an aphidlion, preserved in a piece of Eocene Baltic amber (about 40 million years old). It is preserved together with three possible prey items, wingless aphids, most likely representatives of Germaraphis (or at least closely related to this group). The aphidlion can be identified based on the morphology of the antennae, simple curved and toothless stylets, well developed labial palps, and the absence of other mouth-part structures such as a protruding labrum or maxillary palps. A long, club-shaped distal element of the labial palps identifies the specimen as a larva of Hemerobiidae. The aphids can be identified based on their very long, beak-like mouth parts. This find is, to our knowledge, the first example of a lacewing larva preserved together with its potential prey. We briefly discuss other cases in which fossils preserved in amber allow us to reconstruct aspects of behaviour and interactions of fossil lacewing larvae.

Camouflage strategies, including several types of concealments, are known for several insect groups today, such as immatures of some species within reduviid bugs (Hemiptera), lace wings (Neuroptera), caddisflies (Trichoptera) and bark lice (Psocodea). However, camouflage has only rarely been reported in the fossil record. Here we report findings of four bark lice preserved in 100 Million year old amber from Myanmar, which represent the first fossil evidence for masking behaviour in Cretaceous representatives of Psocodea. All four of these, probably not conspecific, and immature bark lice carry sand granules and organic material atop their back, which probably resulted in camouflaging them against the background (e.g. bark) to avoid detection by predators. We briefly summarise concepts of camouflage and examples of decoration behaviour within insects, as well as possible “receiver” (i.e. predators) of the camouflage of the herein described bark lice. The exact phylogenetic position of the specimens remains unclear, due to the scarce fossil record of Cretaceous immatures of Psocodea, as well as extant immatures. This demonstrates the importance of findings as reported here, as a wide knowledge of morphology and development of a certain group is crucial to get an insight into their evolution and reconstructing environments in deep time.