Lespesia archippivora

(Riley, 1871)

Caterpillar Destroyer

Lespesia archippivora is a that develops internally within , eventually killing its . It is a parasitoid known to infect at least 25 lepidopteran and one species. The species is particularly notable for its impact on , with studies estimating 6.2% of wild monarchs are killed by this fly. It has been widely used as a agent against agricultural pests including , , and . First to Hawaii in 1898 for pest control, it is now established across North America and several Pacific islands.

Lespesia archippivora by (c) Arturo Santos, some rights reserved (CC BY), uploaded by Arturo Santos. Used under a CC-BY license.

Pronunciation

How to pronounce Lespesia archippivora: //lɛˈspiːʒə ˌɑːrˌkɪpɪˈvɔːrə//

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

Identification

Distinguished from other by its association with specific and geographic range. are covered in thick, dark bristles on the . Accurate identification to level requires examination of morphological characters by a ; general field identification is difficult without host association data or specimen examination.

Images

Appearance

are approximately the size of a . The is covered with thick, dark bristles—a distinctive feature of flies. Adults possess the typical dipteran body plan with one pair of functional .

Habitat

Occurs in agricultural fields, gardens, and natural areas where are present. The requires supporting its diverse lepidopteran host range, including fields, meadows, and areas with and other host plants.

Distribution

to North America; established in Canada, United States, and Mexico. to Hawaii in 1898 and subsequently to Fiji, Guam, and Marshall Islands. Present in agricultural and natural landscapes across its range.

Seasonality

One study suggests the is (two per year). Activity coincides with availability of , with rates increasing through larval stages of host development.

Host Associations

Danaus plexippus - ; causes 6.2% mortality in wild
Mythimna unipuncta - ; used in
Helicoverpa zea - ; used in
Agrotis ipsilon - ; used in
Peridroma saucia - ; used in
Spodoptera frugiperda - ; laboratory confirmed
Spodoptera exigua - ; progeny allocation studied
Omiodes accepta - leaf roller; used in
Perilampus hyalinus - that parasitizes L. archippivora

Life Cycle

Females mate within one day of , then locate . are oviposited at the end of the host; eggs are relatively large compared to other . hatch and burrow through the host surface, moving freely within the host body. After three days, the positions itself near a host . The maggot undergoes three larval , consuming internal host contents. It exits the host as a late-stage larva and pupates in soil substrate. emergence occurs 10-14 days after . Total size typically ranges from 1-10 maggots per host. Females lay 15-204 eggs in their lifetime.

Behavior

Females act quickly when locating , ovipositing rapidly at the end of . Exhibits progeny allocation , distributing offspring among available host rather than concentrating in single hosts. move freely within the host body before positioning near .

Ecological Role

Acts as a regulating of lepidopteran . Serves as a for including the Perilampus hyalinus. Contributes to natural mortality factors affecting both and non-target including .

Human Relevance

Widely employed as a agent against agricultural pests since 1898, including the Hawaii introduction by Albert Koebele. Used to manage , , and in protection. A concern for due to documented mortality in wild and reared ; researchers debate whether high regulate monarch populations or affect fall to Mexico.

Similar Taxa

Compsilura concinnataAnother of lepidopteran ; distinguished by introduction (20th century introduction to North America for control) and different host range patterns
Other Lespesia speciesCongeneric such as L. melloi are of different species (e.g., Spanish ); require morphological examination for definitive identification

More Details

Hyperparasitism

Lespesia archippivora can itself be parasitized by . The Perilampus hyalinus has been documented infecting L. archippivora .

Research Significance

Citizen science data from the Project (1999-present) has provided unprecedented documentation of this ' impact on monarch , with over 20,000 specimens monitored and more than 1,100 specimens collected for identification.

Taxonomic Uncertainty

Researchers suspect L. archippivora may represent a 'complex' of multiple closely related , with one potentially specializing on . This remains a of ongoing research.