Hylemya

Robineau-Desvoidy, 1830

root-maggot flies

Species Guides

Hylemya is a of root-maggot flies in the Anthomyiidae, containing at least 30 described . The genus includes several economically significant agricultural pests that attack crop roots and shoots. Species such as Hylemya antiqua (onion maggot), Hylemya brassicae (cabbage ), and Hylemya arambourgi cause damage to cultivated plants including onions, cruciferous vegetables, and cereals. Larvae typically feed below ground on roots or bore into plant shoots, while may feed on nectar or other plant exudates.

Hylemya partita by (c) Zachary Dankowicz, some rights reserved (CC BY), uploaded by Zachary Dankowicz. Used under a CC-BY license.

Hylemya urbica by (c) Bill Keim, some rights reserved (CC BY). Used under a CC-BY license.

Pronunciation

How to pronounce Hylemya: /hɪˈliːmiə/

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

Images

Habitat

Agricultural fields and cultivated areas where crops are grown. have been documented in barley fields in Kenya, onion fields, and cruciferous crop plantings in Canada. Some species utilize alternative grass hosts including Pennisetum clandestinum, Chloris gayana, and Setaria species.

Distribution

Documented from North America (Canada, United States including Florida and Oregon), Europe (Denmark, Norway, Sweden), and Africa (Kenya). Specific distributions vary; Hylemya brassicae, H. floralis, H. planipalpis, and H. cilicrura occur in Canada; H. lupini in Florida; H. arambourgi in Kenya; H. fugax in Oregon.

Diet

Larvae feed on plant roots and shoots. Hylemya antiqua larvae feed on onion (Allium cepa) bulbs and roots. Hylemya arambourgi larvae attack barley shoots, destroying 3-4 shoots per larva. Hylemya brassicae, H. floralis, and H. planipalpis feed on cruciferous crops. feeding habits include nectar consumption; specific adult nutrition has been studied in H. antiqua.

Host Associations

Allium cepa - larval food plantonion
Hordeum vulgare - larval food plantbarley; H. arambourgi
Brassicaceae - larval food plantcruciferous crops; H. brassicae, H. floralis, H. planipalpis
Pennisetum clandestinum - alternative grass
Chloris gayana - alternative grass
Setaria - alternative grass

Behavior

Males of Hylemya alcathoe exhibit stereotyped pre-copulatory courtship including foreleg tapping and wing vibration, with active pursuit of females and male-male competition. Females of H. antiqua use specific -finding mechanisms to locate suitable oviposition sites on host plants. Larvae of H. arambourgi rarely enter soil before , feeding primarily within plant shoots.

Ecological Role

Agricultural pests causing direct damage to crop plants through larval feeding. Hylemya arambourgi can cause complete crop loss under drought conditions with early heavy . The serves as for surveyed for programs in Canada.

Human Relevance

Significant economic impact on agriculture. Hylemya antiqua is a major pest of onion crops. Hylemya brassicae, H. floralis, and H. planipalpis attack cruciferous vegetables. Hylemya arambourgi is an important pest of barley in Kenya. Chemical control studies show with dieldrin and heptachlor were historically effective against H. arambourgi; sprays applied after attack development were of little value. programs have surveyed of Canadian Hylemya .

Similar Taxa

DeliaAlso root-maggot flies in Anthomyiidae; some historically moved between . Hylemya species may be distinguished by specific morphological characters and associations, though precise differentiation requires examination.
PegomyaAnother anthomyiid containing root-feeding . Distinguishing features involve genitalia and larval chaetotaxy, not reliably separable by general appearance alone.

More Details

Chemical Control

Studies on Hylemya arambourgi demonstrated that only were consistently effective for control. Dieldrin and heptachlor at 3.2-5.0 oz per 100 lb seed provided control, likely acting as poisons. Post-attack sprays were ineffective, and pre-sowing treatments other than seed treatments failed at economic rates.

Biological Control Surveys

Canadian surveys identified of Hylemya brassicae, H. floralis, H. planipalpis, and associated H. cilicrura as part of programs against these crucifer pests.