Pachyneuron

Walker, 1833

Pachyneuron is a of in the , comprising approximately 60 valid . Species are primarily of (, , and ), attacking the of these . Some species also hyperparasitize predatory such as () and () via their parasitoids. Certain species, including P. aphidis and P. albutius, have been documented as direct parasitoids of dipteran or . The genus has been studied in the context of , where hyperparasitism may interfere with pest management programs.

Pachyneuron by (c) Victor Engel, some rights reserved (CC BY), uploaded by Victor Engel. Used under a CC-BY license.

Pachyneuron emersoni by the Smithsonian. Used under a CC0 license.

Pronunciation

How to pronounce Pachyneuron: //ˌpækɪˈnjʊərɒn//

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

Images

Habitat

occur in diverse environments including agricultural fields, forests, and urban areas where their are present. Pachyneuron aphidis has been observed foraging on Cirsium arvense in field conditions. Pachyneuron albutius was recorded on Lagerstroemia indica in Panama.

Distribution

distribution. Documented from North America (California, New York), Central America (Panama), Asia (Iran, Kazakhstan, China, Taiwan, India, Jilin, Buryat), and the Caribbean (Saint Vincent and the Grenadines). Specific distribution varies by ; P. muscarum is widely distributed in the Palaearctic with records from the Oriental region and Caribbean.

Seasonality

In the Pacific Northwest, associated with Leucotaraxis argenticollis show highest rates in June and July, with increasing from February through July as activity progresses.

Host Associations

Hemiptera: Sternorrhyncha (aphids, coccids, psyllids) - Primary are of these
Coleoptera: Coccinellidae (ladybird larvae) - Via such as Homalotylus (); at least eight Pachyneuron worldwide reported from
Neuroptera: Chrysopidae (predatory lacewing larvae) -
Diptera: Chamaemyiidae (Leucotaraxis argenticollis, L. piniperda) - Pachyneuron parasitizes or ; prefers L. argenticollis over L. piniperda
Diptera: Syrphidae (Ocyptamus gastrostactus) - pupal P. albutius first recorded as in Panama
Hymenoptera: Encyrtidae (Homalotylus spp., Diaphorencyrtus aligarhensis) - P. muscarum and P. crassiculme documented as of these
Hymenoptera: Eulophidae (Tamarixia radiata) - possible P. crassiculme possibly hyperparasitizes this
Hymenoptera: Aphidiidae (Aphidius gifuensis) - P. aphidis hyperparasitizes this of

Life Cycle

Solitary development. Females lay inside . develop and pupate within the host; in relationships, emerge from mummified hosts. Specific developmental stages targeted vary: some parasitize larvae, others , or both.

Behavior

Females perform slow, extended search within , with 40% of flights resulting in targeted landings near colonies. This flight appears to compensate for reduced speed compared to other . Phototactic behavior has been documented in P. aphidis.

Ecological Role

in involving and their . May disrupt of , , and by parasitizing both the herbivores' and the parasitoids of their . In hemlock woolly management programs, Pachyneuron reduce the effectiveness of silver agents.

Human Relevance

Relevant to programs, particularly as a potential interference agent. Hyperparasitism by Pachyneuron may reduce the efficacy of and predatory released or conserved for pest management. extracts (Azadirachta excelsa, Xanthium italicum) have been tested for to Pachyneuron species to selectively reduce pressure on insects.

Similar Taxa

MelanipsAlso a attacking Leucotaraxis ; Melanips prefers L. piniperda while Pachyneuron prefers L. argenticollis
AsaphesAnother in associated with ; co-occurs with Pachyneuron in some systems

More Details

Morphological adaptations

Geometric morphometric studies of P. aphidis show narrow shape and widened as significant characteristics of high-altitude . Body size (centroid size, forewing and thorax dimensions) increases at higher elevations.

Sensilla morphology

P. aphidis possesses seven of : Böhm bristle, chaetica sensilla, basiconic sensilla, trichoid sensilla (with subtypes on and ), placodea sensilla, coeleoconica sensilla, and basiconic peg sensilla. Sensilla are most abundant on antennae. in sensilla location exists: coeleoconica sensilla occur on the fourth in males and eighth flagellomere in females.