Identification of encyrtid wasps

Encyrtidae is a family of small (< 5 mm) parasitic wasps. These are fairly easy to identify to family level (with reasonable-quality photos), but it is far more difficult to find the genus, unless the individual is from one of the few genera that are easily recognised.

These are features of the family:

• Large mesopleuron, usually covering more than half of the thorax (mesosoma) in side view.
• Mid coxae join the thorax near the middle of the mesopleuron.

Encyrtid parasitic wasp - lateral view. https://commons.wikimedia.org/wiki/File:Encyrtidae_lateral_view_with_annotations.jpg

• Mesoscutum transverse (width greater than length), and generally not segmented by notauli.
• The axillae are usually visible as triangles with two long sides, one adjacent to the mesoscutum and the other adjacent to the scutellum; the short side of the triangle is adjacent to the base of the forewing. The axillae touch, or nearly touch, medially; appearing as wedges between the mesoscutum and the scutellum.

Encyrtid parasitic wasp - dorsal view. https://commons.wikimedia.org/wiki/File:Encyrtidae_dorsal_view_with_annotations.jpg

• Cercal plates (at the base of the cercal bristles) are advanced; rather than being near the posterior tip of the metasoma (abdomen); they are usually within the anterior (front) two-thirds of the metasoma.

Encyrtid parasitic wasp - dorso-lateral view. https://commons.wikimedia.org/wiki/File:Encyrtidae_dorso-lateral_view_with_annotations.jpg

• In Encyrtidae with fully developed wings, the marginal vein of the forewing is usually shorter than stigmal vein; there is also an oblique band on the forewing that lacks setae (a linea calva).

Forewing of Anagyrus minipedicellus - from Zu, G. H., Zhang, X., & Zhang, Y. Z. (2018). A new species of Anagyrus (Hymenoptera, Encyrtidae) from Malaysia, parasitoid of Lanceacoccus sp.(Hemiptera, Pseudococcidae). Journal of Hymenoptera Research, 65, 141-148. https://commons.wikimedia.org/wiki/File:Forewing_of_Anagyrus_minipedicellus_from_Malaysia_Fig7_Zu_et_al_2018.jpg

There is a key to the Afrotropical encyrtid genera (Prinsloo and Anneke, 1979 https://journals.co.za/doi/pdf/10.10520/AJA00128789_2641), but effective use of the key usually needs a specimen under a microscope. I am in the process of using the key as a basis for a guide that includes photographs, created mainly to see whether I can get my head around the group (I'm still floundering). The guide (https://en.wikiversity.org/wiki/African_Arthropods/Afrotropical_Encyrtidae_Key) is on Wikiversity as part of a project called "African Arthropods" (https://en.wikiversity.org/wiki/African_Arthropods).

Please feel free to edit or add to the Wikiversity project.

Publicado el marzo 15, 2024 09:19 MAÑANA por alandmanson