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ABSTRACT Alluaud's little yellow ant,Plagiolepis alluaudiEmery 1894, (Hymenoptera: Formicidae), is an emerging nuisance species in floriculture and residential areas around the globe. Originally described from Madagascar, it ranks among the smallest widespread formicine pests. To date, no evaluations of management protocols for this species have been reported. In ants, feeding preference is related to ant body size and viscosity and nutritional content of the food source. Optimizing these factors could lead to improved bait performance. To assess population management implications of various bait parameters on a small pest ant species, four commercial ant baits of varying viscosities, active ingredient (AI) group and concentration, and nutritional content were evaluated in laboratory and field assays againstP. alluaudi. All four products negatively affectedP. alluaudisurvival compared to the untreated control, and all products were associated with greater visitation compared to the control, suggesting all AIs tested are viable candidates forP. alluaudimanagement. However, their direct use for population management in the field may be limited, as feeding cessation was eventually observed on all four baits. When baits were diluted with water, viscosity was reduced and survival was initially higher compared to with undiluted baits. However, similarly low levels of survival were maintained over time. Most importantly, we found in a 2‐year observational field study involving sustained baiting within an infested structure that only the bait formulation with the lowest overall viscosity was able to alleviateP. alluaudinuisance indoors. Our results suggest that diluting baits may be a viable strategy for targeting very small pest ant species, and the greater time to lethality of diluted baits, resulting from reduced toxicant concentration, may be a reasonable trade‐off allowing smaller ant species to continue feeding for a sufficient duration on a bait formulation. 

Many host-symbiont relationships are maintained through vertical transmission. While maternal symbiont transmission is common, biparental transmission is relatively rare. Protist-dependent termites are eusocial insects that harbor obligate, cellulolytic protists in their hindguts. Protists are vertically transmitted by winged reproductives (alates), which disperse to biparentally establish new colonies. Vertical transmission in protist-dependent termites is imperfect, as the protist communities of alates are often incomplete. Biparental transmission of protists may make it unnecessary for alates to harbor complete communities, as colonies would acquire symbionts from both founding kings and queens, which together may harbor sufficient inoculums. To investigate this hypothesis, the protist communities of Coptotermes gestroi and C. formosanus alates and colonies were examined using 18S rRNA amplicon sequencing. The complete protist communities of these Coptotermes species are composed of five parabasalid species each. Whereas alates often harbored 1–3 protist species, nearly all colonies harbored 4–5 species, implying biparental transmission. The probability of each protist species being present in at least one founding alate was used to determine expected protist occurrence in colonies. For most protists, expected and observed occurrence did not significantly differ, suggesting that each protist species only needs to be harbored by one founding alate to be acquired by colonies. Our results imply that biparental transmission allows founding reproductives to transmit adequate symbiont communities to colonies despite their individual communities being incomplete. We discuss biparental transmission in protist-dependent termites in the context of other biparentally transmitted symbioses. 

ABSTRACT Termites have a unique ability to effectively digest lignocellulose with the help of mutualistic symbionts. While gut bacteria and protozoa have been relatively well characterized in termites, the virome remains largely unexplored. Here, we report two genomes of microviruses (termite-associated microvirus-1 [TaMV-1] and termite-associated microvirus-2 [TaMV-2]) associated with the gut of Coptotermes formosanus . 

Abstract Coptotermes formosanusShiraki andCoptotermes gestroi(Wasmann) (Blattoidea: Rhinotermitidae) are invasive subterranean termite pest species with a major global economic impact. However, the descriptions of the mutualistic protist communities harbored in their respective hindguts remain fragmentary. TheC. formosanushindgut has long been considered to harbor three protist species,Pseudotrichonympha grassii(Trichonymphida),Holomastigotoides hartmanni, andCononympha(Spirotrichonympha)leidyi(Spirotrichonymphida), but molecular data have suggested that the diversity may be higher. Meanwhile, theC. gestroicommunity remains undescribed except forPseudotrichonympha leei. To complete the characterization of these communities, hindguts of workers from both termite species were investigated using single‐cell PCR, microscopy, cell counts, and 18S rRNA amplicon sequencing. The two hosts were found to harbor intriguingly parallel protist communities, each consisting of onePseudotrichonymphaspecies, twoHolomastigotoidesspecies, and twoCononymphaspecies. All protist species were unique to their respective hosts, which last shared a common ancestor ~18 MYA. The relative abundances of protist species in each hindgut differed remarkably between cell count data and 18S rRNA profiles, calling for caution in interpreting species abundances from amplicon data. This study will enable future research inC. formosanusandC. gestroihybrids, which provide a unique opportunity to study protist community inheritance, compatibility, and potential contribution to hybrid vigor.