Pamphilius ochreipes

Cresson

Viburnum Web-spinning Sawfly

Pamphilius ochreipes is a web-spinning in the Pamphiliidae. Larvae feed within leaf rolls on cultivated Viburnum opulus, constructing silk webbing for protection. The has a , as larvae in soil and emerging as in late spring. Adults have been collected across North America, though detailed biological studies are limited to southern Ontario .

Pronunciation

How to pronounce Pamphilius ochreipes: /pæmˈfɪliəs oʊˈkriːiːˌpɛs/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from other Pamphilius by association with Viburnum plants and the distinctive leaf-rolling of larvae. require expert identification; examination of genitalia or other microscopic features may be necessary for definitive separation from .

Habitat

Cultivated and presumably wild Viburnum stands; larval microhabitat consists of rolled or folded leaves bound with silk webbing. larvae occur in soil.

Distribution

North America: Canada (Ontario, Alberta, British Columbia, Manitoba, Nova Scotia); United States distribution includes Arkansas based on recent records. collected widely across continent, though confirmed breeding documented primarily in southern Ontario.

Seasonality

in late May and early June; larval feeding occurs in June. with single per year.

Diet

Larvae feed on leaves of Viburnum opulus L. (cultivated guelder-rose). No other plants confirmed.

Host Associations

  • Viburnum opulus - larval food plantcultivated plants in southern Ontario; wild may use other Viburnum but unconfirmed

Life Cycle

. laid into leaf tissue. Larvae feed within silk-bound leaf rolls, then drop to soil to overwinter. occurs in soil; emerge following spring. No evidence of extended or multiple .

Behavior

Larvae are web-spinners, constructing silk shelters within rolled or folded leaves. This distinguishes Pamphiliidae from most other . Larvae feed gregariously within these shelters.

Ecological Role

Herbivore on Viburnum; may cause minor foliar damage to cultivated plants. Serves as prey for and , though specific natural enemies unstudied.

Human Relevance

Minor potential pest of cultivated Viburnum opulus (guelder-rose) in ornamental settings. No economic significance to agriculture or forestry. Harmless to humans—lacks stinging apparatus.

Similar Taxa

  • Other Pamphilius speciesMany Pamphilius are web-spinners with similar ; plant association and geographic distribution are primary distinguishing features. P. ochreipes specifically associated with Viburnum.
  • Tenthredinidae (common sawflies)Larvae of many tenthredinids feed on leaves but lack silk-spinning ; most have exposed feeding habit rather than constructing leaf rolls.

More Details

Study limitations

Detailed biological information derives primarily from a single study in southern Ontario. range may be broader than Viburnum opulus; wild may utilize additional Viburnum . Arkansas records represent significant range extension but breeding unconfirmed in that region.

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Sources and further reading