Puss Caterpillar (Asp)
Also known as asp, flannel moth caterpillar. Megalopyge opercularis
Florida's most venomous caterpillar — looks like a fluffy teardrop and hides in oak trees.
In Florida, Puss Caterpillar (Asp) (Megalopyge opercularis) rates as a dangerous concern. General pest control in Florida's Treasure & Space Coast is handled by Rhino Pest Management, a local, licensed (#JB242881) and insured company rated 5.0★ across 16 Google reviews. Ask for a free estimate at (772) 589-6842.
Photo: Iose (Public domain) · Wikimedia Commons
About 25–35 mm, entirely covered in soft, teardrop-shaped, tan-to-gray fur — it looks like a tiny toupee or a fluffy oval. The fur hides sharp venomous spines beneath. Adults become the white flannel moth.
Oak, elm and hackberry trees near parks, yards, schools and playgrounds across Florida. They drop from trees in late summer and fall, landing on people walking below.
- Furry, teardrop-shaped caterpillars on oak leaves, elm or hackberry trees
- Caterpillars dropping from trees in fall and spring
- Intense, immediate pain — like a burn — after contact with what looked like a fuzzy caterpillar
- A grid-like pattern of red welts at the contact site
Contact with the puss caterpillar's hidden spines causes immediate, intense burning pain, a characteristic grid-pattern rash, headache, nausea and occasionally respiratory distress. It is Florida's most medically significant caterpillar. Remove spines with tape and seek medical care if symptoms are severe.
Should I call today?
Yes — treat this as a priority. Puss Caterpillar (Asp) poses a real risk to people or pets, so don't try to handle it yourself: disturbing it is how most people get hurt. Keep everyone clear of the area and get a professional out to identify and remove it.
Rhino treats infested trees with a product that targets caterpillars and reduces the population on and around structures where contact risk is highest.
Our General Pest Control servicePuss Caterpillar (Asp) guides
More stinging insects
Aggressive ground-nesting wasps that sting repeatedly and defend nests violently.
ViewLong-legged brown-and-yellow wasps that build open umbrella nests under eaves and furniture.
ViewSolitary wasps that build mud tube nests on walls and pack them with paralyzed spiders.
ViewScientific source
For the biology behind this page, the University of Florida's IFAS Extension publishes a detailed Featured Creatures profile of this species — free to read, and written by entomologists in this state:
Puss Caterpillar (Larva), Southern Flannel Moth (Adult), Megalopyge opercularis (J. E. Smith 1797) — UF/IFAS Extension