Lerp

Definition

A protective, often conical or plate-like structure of crystallized honeydew and wax secreted by nymphs of psyllid insects (Hemiptera: Psylloidea) over their bodies while feeding on plant phloem. Lerps shield the soft-bodied nymph from desiccation, predators, and environmental hazards; their size, shape, and chemistry vary among species and host plants, and heavy infestations can cause significant damage to Eucalyptus and other host trees.

Etymology

From Australian English, possibly of Aboriginal origin or imitative of the sound of peeling the brittle structure from leaves.

Example

The red gum lerp psyllid (Glycaspis brimblecombei), an invasive pest in California, produces distinctive white, conical lerps up to 6 mm in diameter on Eucalyptus leaves; nymphs remain sheltered beneath until the lerp is shed or the adult emerges.

Related Terms

• psyllid
• honeydew
• Exuviae
• gall
• stylet sheath
• phloem feeder
• Eucalyptus pest

Usage Notes

Strictly refers to psyllid constructions; not used for the waxy coverings of aphids (flocculent wax), scale insects (test), or other Hemiptera. Specialists distinguish 'lerp' (the structure) from 'lerp insect' (the psyllid producing it). The term is most common in Australian and Californian agricultural entomology due to economic impacts on eucalypts.