Ancient pinnate leaf mimesis among lacewings

Area of Science:

• Paleontology
• Evolutionary Biology
• Entomology

Background:

• Insects exhibit diverse predator avoidance strategies, including wing adaptations like leaf mimicry.
• The evolutionary origins of leaf mimicry, particularly before flowering plants, are poorly understood due to limited fossil evidence.

Purpose of the Study:

• To investigate the early evolution of leaf mimicry in insects.
• To uncover evidence of insect-gymnosperm interactions during the Mesozoic Era.

Main Methods:

• Description and analysis of two new lacewing fossil species (Bellinympha filicifolia and Bellinympha dancei) from the Middle Jurassic.
• Paleontological examination of wing morphology and its resemblance to contemporaneous gymnosperm foliage.

Main Results:

• Discovery of Middle Jurassic lacewings exhibiting pinnate leaf mimicry, dating this specialization to at least 165 million years ago.
• Evidence suggests this mimicry involved interactions with ancient gymnosperms (Cycadales or Bennettitales), predating the rise of angiosperms.
• The fossil lineage appears to have gone extinct in the Early Cretaceous, potentially linked to the decline of these gymnosperms and the rise of flowering plants.

Conclusions:

• Leaf mimicry in insects originated before the evolution of flowering plants, involving interactions with gymnosperms.
• This finding highlights a previously unknown evolutionary scenario of insect-plant relationships.
• The extinction of this lacewing lineage may correlate with significant environmental and floral changes in the Cretaceous period.