Winthemia

Robineau-Desvoidy, 1830

Winthemia is a of (: ) comprising over 100 described distributed worldwide. Species in this genus are of , with developing internally in . Several species have been studied as agents of agricultural pests, including W. rufopicta on Heliothis species, W. fumiferanae on , and W. manducae on . The genus exhibits protandry in and shows complex interactions with host .

Distribution

Winthemia have been recorded across multiple continents including North America, South America, Europe, Asia, and Africa. GBIF distribution records confirm presence in Denmark, Norway, and Sweden. Individual species show varying geographic ranges: W. rufopicta occurs in North America, W. fumiferanae in North America (Quebec), W. citheroniae in regions where large occur, and W. sumatrensis in South Asia (South Karnataka, India).

Seasonality

Winthemia rufopicta shows beginning in April in North Carolina, with males preceding females by approximately one week. Winthemia fumiferanae exhibits adult emergence synchronized with second to fifth , with peaking when sixth-instar are abundant. Multiple overlapping occur through the growing season, with declining in spring due to host shortage and building through summer and fall.

Diet

Winthemia have been observed feeding on nectar and . are obligate , feeding internally on tissues.

Life Cycle

are deposited on the exterior of . First enter the host and develop internally, feeding on host tissues. Mature larvae exit the host to pupate in the soil, typically in shallow between 0 and 40 mm below the surface. Winthemia rufopicta overwinters as fully grown diapausing in soil cells. Winthemia fumiferanae shows egg hatching triggered by host . Development rates are temperature-dependent, with egg and larval development times varying with thermal conditions.

Behavior

of some are and active during daylight hours. Females exhibit -searching , orienting to host plants and investigating potential hosts. Winthemia fumiferanae shows protandry, with males emerging before females. Females emerge with undeveloped and abundant fat reserves; maturation completes within approximately two weeks after . behavior includes preference for larger host and selection of stage based on host and larval concealment.

Ecological Role

Winthemia function as larval of , contributing to of species. Several species are significant mortality agents of agricultural and forestry pests, including , , and Heliothis species. The represents part of the diverse parasitoid complex that helps maintain balance in natural and managed .

Human Relevance

Several Winthemia have been investigated for of agricultural and forestry pests. Winthemia rufopicta has been studied as a of Heliothis zea and H. virescens on . Winthemia fumiferanae is a parasitoid of , a major defoliator of spruce-fir forests. Winthemia manducae parasitizes the , an agricultural pest of tobacco and tomato.