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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Systematic Entomology Laboratory » Research » Publications at this Location » Publication #377227

Research Project: Systematics of Hemiptera and Related Groups: Plant Pests, Predators and Disease Vectors

Location: Systematic Entomology Laboratory

Title: Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania

item Schneider, Scott
item LAPOLLA, JOHN - Towson University

Submitted to: Zootaxa
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/26/2020
Publication Date: 9/22/2020
Citation: Schneider, S.A., Lapolla, J.S. 2020. Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa. 4853(2):283-291.

Interpretive Summary: Root mealybugs are an understudied group of scale insects, despite their potential, and often demonstrated, importance to agriculture. The group is relatively understudied due to their underground habit, but they are known to feed on important crops such as banana, coffee, and cacao, and their populations are often protected from natural enemies by associated ants. This study describes a new species of root mealybug that associates with ants; it expands our knowledge about a rarely collected genus of root mealybugs and provides an updated guide to their identification. Furthermore, it provides insights into the evolution of obligatory relationships between groups of scale insects and ants, which has significance not only to agricultural research but to basic scientific research about the ecology of mutualisms.

Technical Abstract: A new myrmecophilous species of root mealybug, Williamsrhizoecus udzungwensis sp. nov., is described from individuals found living within a nest of Acropyga silvestrii in the Udzungwa Mountains of Tanzania. Acropyga ants are highly specialized obligate associates of scale insects, typically members of the family Xenococcidae. Acropyga are best known for vertically transmitting trophobiotic partners during their nuptial flights and for housing them within brood chambers. This article presents the first record of trophobiosis between a species of Williamsrhizoecus and Acropyga, and only the second record of association between Acropyga and rhizoecids occurring in the Old World. This discovery contributes important information about the few species of Rhizoecidae confirmed to engage in these unique symbioses, each putatively the result of a past horizontal transmission event from a xenococcid to rhizoecid lineage. Included is a discussion on the diagnosis of Williamsrhizoecus and an updated key to the species.