## 2 Results and Discussion
### Test of EAG  
In the EAG bioassays, the antennae of female individuals of _C. lunulata_ to the VOCsB of _M. morganii_ (Figure 4) presented a statistically significant greater response to VOCsB than to the control (\(t=2.80\), n = 11, \(p=0.01\)).  
From the antennal response to VOCsB of _Ci. freundii_ and _K. oxytoca_ (Figure 5), the antennae of male _C. barrerai_ presented a statistically significant greater response to VOCsB than to the control (F = 7.19, df = 9, \(p<0.01\)). In _C. lunulata_, the females presented a statistically significant greater response to VOCsB than to the control (F = 5.272, df = 11, \(p=0.01\)) and males (F = 4.022, df = 10, \(p=0.03\)).  
Figure 4: Antennal depolarization of _Cyclocophila lunulata_ at VOCsB of _Morganella morganii_. The asterisk indicates significant differences in the paired \(t\)-test (n = 11, \(p>0.05\)).  
Figure 3: Attraction of females (n = 18) and males (n = 18) of _Cyclocophila lunulata_ towards the VOCsB of the bacteria resident of the genital chamber of females of _Cyclocophila barrerai_. The asterisk indicates significant differences in \(\chi^{2}\) test, and \(p>0.05\)).  
In view of the above, the EAG tests revealed that those compounds produced antennal responses where phenol showed the greatest effects. EAG tests are important to ensure that the insect recognizes the substance to which it is exposed [62]. The attraction of beetles to VOCsB has been widely studied; however, the study of the antennal response has not, whereas EAG studies have been carried out for pheromones, allowing to relate attraction and recognition in the insect [7]. In this study, it was observed that VOCsB caused antennal depolarization, particularly those containing aromatic alcohols, such as phenol and 2-phenylethanol.  
The attraction of both male and female individuals of _C. lunulata_ towards several of the VOCsB indicates that these are aggregation attractants [62, 63]. Aggregation has been cited for species from Dynastinae; although the production of these chemical substances has been primarily associated with males [64, 65, 66, 37, 67, 68, 69], there are reports of female beetles emitting this type of pheromone as well [70, 71]. In this study, the females of _Cyclochepala_ produced the compounds, possibly with the assistance of bacteria associated with their genital chamber, and this coincides with other studies reporting that VOCsB act as aggregation attractants for their insect hosts [35, 36]. In other studies, the VOCsB of _Bactrocera zonata_ [PERSON] attract a greater number of females [18], and the VOCsB from the intestinal microbiota of _Dendroctous ponderosae_ [PERSON] provoke aggregation for the mass invasion of trees [72].  
The emission of alcohols by bacteria from the genital chamber of _C. lunulata_ could also serve a defensive role against pathogenic microorganisms, in addition to their function in insect chemical communication. Alcohol derivatives such as phenol and, particularly, long-chain alcohols are usually produced by members of Enterobacteriaceae [25], and they inhibit the growth and development of Gram-positive bacteria, fungi [2, 73], and the most representative species of insect pathogens [74]. This could explain why, until now, all bacteria isolated from the female reproductive apparatus of Melolonthidae beetles belonged to Enterobacteriaceae. For instance, the intestinal bacteria of _Schistocerca gregaria_[35] act primarily as a form of defense and participate in the synthesis of food and secondarily function in the chemical communication of the host. Therefore, bacteria from different species are metabolically similar and emit similar compounds [18].