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We describe a new pair of trophobiotic partners from the ant genus Acropyga and the root mealybug genus Neochavesia . A recent field study on Acropyga ants and associated root mealybugs, conducted in the Peruvian Amazon, led to the discovery of Acropyga manuense LaPolla & Schneider, sp. nov. and its root mealybug symbiont Neochavesia podexuta Schneider & LaPolla, sp. nov. The new root mealybug belongs to the family Xenococcidae, whose members are all obligate associates of Acropyga ants. Providing joint descriptions of new mutualist partners in the same article is a novel approach for this system, and it offers benefits to the ongoing study of mutualism and patterns of association among these symbiotic ants and scales. Here, we also begin to revise the species-group composition of Acropyga by establishing the smithii species-group, and we provide updated information to aid in identifying the new ant species and root mealybug species.
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Scale insect (Hemiptera: Coccomorpha) morphology is transformed under trophobiosis
Abstract Ants (Hymenoptera: Formicidae) have great potential to exert influence over the morphological evolution of their obligate mutualist partners. Obligately myrmecophilic mealybugs are noted for their unusual morphology, and while this is often attributed to their relationship with ants, a quantitative assessment of this link is lacking. We address this need by evaluating morphological change among mealybugs as a function of ant association. This study considers the associates of 2 independent ant clades—Acropyga Roger, 1862 ants associated with root mealybugs from the families Xenococcidae and Rhizoecidae and herdsmen ants from the Dolichoderus cuspidatus (Smith, F., 1857) species-group associated with mealybugs from the tribe Allomyrmococcini (Pseudococcidae)—and compares them to free-living or potentially myrmecophilic species sampled from among the mealybugs and root mealybugs. We use a combination of geometric morphometric and linear datasets to evaluate characteristics of body shape, body size, leg metrics, and ostiole development. Obligate myrmecophily significantly influences both body shape and size. Myrmecophilous mealybugs are smaller than their free-living counterparts and are either pyriform or rotund in shape rather than oval. Ant-associates from Rhizoecidae also have significantly reduced anterior pairs of ostioles compared to free-living species. Ostioles are involved in defense against natural enemies and mutualist ants typically protect their partners, presumably supplanting the need for structures like ostioles among myrmecophilous species. We discuss the influence ants have on the evolution of their associates in the context of domestication and offer avenues for future exploration.
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- Award ID(s):
- 1754242
- PAR ID:
- 10560608
- Editor(s):
- Solis, Alma
- Publisher / Repository:
- Entomological Society of America
- Date Published:
- Journal Name:
- Annals of the Entomological Society of America
- Volume:
- 117
- Issue:
- 1
- ISSN:
- 0013-8746
- Page Range / eLocation ID:
- 49 to 63
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/aesa/saad033
