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Fungivorous millipedes (subterclass Colobognatha) likely represent some of the earliest known mycophagous terrestrial arthropods, yet their fungal partners remain elusive. Here we describe relationships between fungi and the fungivorous millipede, Brachycybe lecontii. Their fungal community is surprisingly diverse, including 176 genera, 39 orders, four phyla, and several undescribed species. Of particular interest are twelve genera conserved across wood substrates and millipede clades that comprise the core fungal community of B. lecontii. Wood decay fungi, long speculated to serve as the primary food source for Brachycybe species, were absent from this core assemblage and proved lethal to millipedes in pathogenicity assays while entomopathogenic Hypocreales were more common in the core but had little effect on millipede health. This study represents the first survey of fungal communities associated with any colobognath millipede, and these results offer a glimpse into the complexity of millipede fungal communities.

Simple Summary: Recent research has demonstrated that contact pheromone components of the female Asian longhorned beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae: Lamiinae), are potential precursors that can undergo abiotic oxidation to yield volatile attractants. That study uncovered the basic mechanism of female volatile production, but the identified component blend was incomplete. The main aim of this study was to identify the missing volatile components from female body wash extracts and test them for behavioral activity using laboratory assays and field trials. We identified several new components from ozone- and UV-treated female extracts using coupled gas chromatography–mass spectrometry (GC-MS) and gas chromatography–electroantennographic detection (GC-EAD). Male adult beetles were highly attracted to a blend of these seven new components in olfactometer tests, and males were primarily attracted to traps in the field when this seven-component blend was used. These newly identified compounds are discussed in relation to pheromones and host volatiles that A. glabripennis potentially utilizes in mate location. The Asian longhorned beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae: Lamiinae), is a serious pest of over 43 species of hardwood trees in North America, China and Europe. The development of an effective lure and trap for monitoring A. glabripennis has been hindered by the fact that mate finding involves a rather complex series of behaviors and responses to several chemical (and visual), cues. Adults (female-biased) locate a tree via host kairomones. Research has demonstrated that female contact pheromone components are precursors that undergo abiotic oxidation to yield attractive volatile components. Males also produce a pheromone to attract other adults nearby before the final step of recognition by males to the female-produced trail and contact pheromones. Our research aimed to identify new female-produced components from ozone and UV-treated A. glabripennis body washes and test them for behavioral activity using laboratory and field assays. The ozone and UV treatment of virgin female extract yielded sixteen aldehydes, nine of which were found in trace amounts. All sixteen aldehydes elicited antennal responses (GC-EAD) in both males and females, although responses were clearer and more distinct with standards of hexanal, heptanal, octanal, nonanal, decanal, undecanal and dodecanal. Olfactometer assays showed that males were highly attracted to a blend of these seven aldehydes. Females did not show any attraction to the blend in olfactometer assays. Despite low population levels during field tests in 2018 in China, traps containing the aldehyde blend detected A. glabripennis on a weekly basis over 6 weeks and caught significantly more adults (mainly males) than control 'flight intercept panel' traps. Field tests in China in 2019 that used the aldehyde blend along with a three-component host blend lure also caught significantly more males (nearly 5×) than blank control traps. [ABSTRACT FROM AUTHOR]

With fossil representatives from the Silurian capable of respiring atmospheric oxygen, millipedes are among the oldest terrestrial animals, and likely the first to acquire diverse and complex chemical defenses against predators. Exploring the origin of complex adaptive traits is critical for understanding the evolution of Earth's biological complexity, and chemical defense evolution serves as an ideal study system. The classic explanation for the evolution of complexity is by gradual increase from simple to complex, passing through intermediate "stepping stone" states. Here we present the first phylogenetic-based study of the evolution of complex chemical defenses in millipedes by generating the largest genomic-based phylogenetic dataset ever assembled for the group. Our phylogenomic results demonstrate that chemical complexity shows a clear pattern of escalation through time. New pathways are added in a stepwise pattern, leading to greater chemical complexity, independently in a number of derived lineages. This complexity gradually increased through time, leading to the advent of three distantly related chemically complex evolutionary lineages, each uniquely characteristic of each of the respective millipede groups.

Simple Summary: Evidence suggesting that the invasive species spotted lanternfly (SLF), Lycorma delicatula, may use pheromones has previously been shown. We hypothesized that sunlight might play a key role in SLF pheromone production based on observations that SLF adults spend time in the upper canopies of their host trees and their affinity for ultraviolet light. In this study, extracts from SLF nymphs and adults were either exposed to simulated sunlight (photo-degradation), or not exposed to light (crude), while volatiles were collected. Attraction of SLF nymphs and adults to volatiles from photo-degraded and crude samples, and their residues, was measured in dual-choice bioassays. SLF nymphs and adults responded differently to either residues or volatiles of both crude and photo-degraded body extracts. Photo-degradation did not increase the attraction of SLF individuals tested in two-choice bioassays, except for third instars. However, SLF males chose the residue from photo-degraded extracts over the residue from crude extracts of females. The results suggest that photo-degradation may play a role in sex-specific short-range communication, but photo-degradation did not appear to play a substantial role in long-range intraspecific chemical communication in SLF. This study produced additional evidence that SLF likely use pheromones in aggregation and mating. Since its discovery in North America in 2014, the spotted lanternfly (SLF), Lycorma delicatula, has become an economic, ecological, and nuisance pest there. Developing early detection and monitoring tools is critical to their mitigation and control. Previous research found evidence that SLF may use pheromones to help locate each other for aggregation or mating. Pheromone production necessitates specific conditions by the insects, and these must be investigated and described. A chemical process called photo-degradation has been described as a final step in the production of pheromones in several diurnal insect species, in which cuticular hydrocarbons were broken down by sunlight into volatile pheromone components. In this study, photo-degradation was investigated as a possible pheromone production pathway for SLF. Extracts from SLF mixed-sex third and fourth nymphs and male or female adults were either exposed to simulated sunlight to produce a photo-degradative reaction (photo-degraded), or not exposed to light (crude), while volatiles were collected. Behavioral bioassays tested for attraction to volatiles from photo-degraded and crude samples and their residues. In third instars, only the volatile samples from photo-degraded mixed-sex extracts were attractive. Fourth instar males were attracted to both crude and photo-degraded residues, and volatiles of photo-degraded mixed-sex extracts. Fourth instar females were attracted to volatiles of crude and photo-degraded mixed-sex extracts, but not to residues. In adults, only males were attracted to body volatiles from crude and photo-degraded extracts of either sex. Examination of all volatile samples using gas chromatography coupled with mass spectrometry (GC-MS) revealed that most of the identified compounds in photo-degraded extracts were also present in crude extracts. However, the abundance of these compounds in photo-degraded samples were 10 to 250 times more than their abundance in the crude counterparts. Results from behavioral bioassays indicate that photo-degradation probably does not generate a long-range pheromone, but it may be involved in the production of a short-range sex-recognition pheromone in SLF. This study provides additional evidence of pheromonal activity in SLF. [ABSTRACT FROM AUTHOR]

The fungus-growing ant Mycetomoellerius (previously Trachymyrmex) zeteki (Weber 1940) has been the focus of a wide range of studies examining symbiotic partners, garden pathogens, mating frequencies, and genomics. This is in part due to the ease of collecting colonies from creek embankments and its high abundance in the Panama Canal region. The original description was based on samples collected on Barro Colorado Island (BCI), Panama. However, most subsequent studies have sampled populations on the mainland 15 km southeast of BCI. Herein we show that two sibling ant species live in sympatry on the mainland: Mycetomoellerius mikromelanos Cardenas, Schultz, & Adams and M. zeteki. This distinction was originally based on behavioral differences of workers in the field and on queen morphology (M. mikromelanos workers and queens are smaller and black while those of M. zeteki are larger and red). Authors frequently refer to either species as "M. cf. zeteki," indicating uncertainty about identity. We used an integrative taxonomic approach to resolve this, examining worker behavior, chemical profiles of worker volatiles, molecular markers, and morphology of all castes. For the latter, we used conventional taxonomic indicators from nine measurements, six extrapolated indices, and morphological characters. We document a new observation of a Diapriinae (Hymenoptera: Diapriidae) parasitoid wasp parasitizingM. zeteki. Finally, we discuss the importance of vouchering in dependable, accessible museum collections and provide a table of previously published papers to clarify the usage of the name T. zeteki. We found that most reports of M. zeteki or M. cf. zeteki-including a genome-actually refer to the new species M. mikromelanos. [ABSTRACT FROM AUTHOR]

NMR spectroscopic studies, using unlabeled and deuterated samples, shed light on the tautomeric behavior of phosphono enamines. The phosphonates are intermediates in the Emmons version of the Wittig reaction used in the synthesis of the Megalomyrmex ant venom. The studies clearly point to a facile imine-enamine double-bond tautomerism between the pyrrolidine and the pyrroline forms, with the olefinic bond resonating between N-1 of pyrroline and C-alpha of the pyrrolidine. The earlier confusion in characterization is traced to the obscuring effect of the substitutents.

A previously unidentified class of compounds has been isolated from the regurgitant of the grasshopper species Schistocerca americana. These compounds (named here ‘caeliferins’) are composed of saturated and monounsaturated sulfated α-hydroxy fatty acids in which the ω-carbon is functionalized with either a sulfated hydroxyl or a carboxyl conjugated to glycine via an amide bond. The regurgitant contains a series of these compounds with fatty acid chains of 15–20 carbons and in varying proportions. Of these, the 16-carbon analogs are predominant and are also most active in inducing release of volatile organic compounds when applied to damaged leaves of corn seedlings. Caeliferins are nonlepidopteran elicitors identified in insect herbivores. This adds a category of insect herbivore-produced elicitors of plant responses, providing further evidence of the ability of plants to detect and respond to a broad range of insect herbivore-produced compounds. [ABSTRACT FROM AUTHOR]