Macalla thyrsisalis

Definition

A species of snout moth (family Pyralidae) distributed across the Caribbean, Central America, and northern South America. The larvae are known as mahogany webworms and feed on Swietenia mahagoni and related Meliaceae, spinning silk webbing over foliage and young stems. Adults are small, relatively inconspicuous pyralids with wingspans typically under 20 mm.

Etymology

From Greek thyrsos (thyrsus, a staff or wand tipped with a pine cone) and the Latin suffix -alis, likely referring to some aspect of the adult morphology or larval webbing; the genus Macalla is of uncertain derivation.

Example

Macalla thyrsisalis larvae can cause significant defoliation of young mahogany plantings in southern Florida nurseries, requiring monitoring during the wet season when webbing becomes conspicuous on terminal shoots.

Synonyms

• mahogany webworm moth

Related Terms

• Pyralidae
• Phycitinae
• snout moth
• webworm
• Swietenia
• larval shelter

Usage Notes

The common name mahogany webworm moth properly refers to the adult; the damaging stage is the larval mahogany webworm. Not to be confused with the related Macalla zelleri, which occurs in similar regions but has distinct larval host preferences. Walker’s original 1859 description was based on specimens from the Amazon region.