Camponotus Research Articles

PENINGKATAN PEMASARAN PADA UMKM LAHANG AREN GULA SEMUT DANWEDANG JAHE MELALUI DIGITAL DI DESA WAY KALAM KECAMATAN PENENGAHAN KABUPA1TEN LAMPUNG SELATAN

The community service work practice program is a means of self-actualization of several skills orskills, both soft skills or hard skills that have been obtained during lectures, which will be applied inthe community for 1 month.In this community service practice report, our participants will take partin the Program, which is located in Way Kalam Village and Gula Semut UMKM, South Lampung for 1 month, from January 31, 2022 to March 2, 2021.The placement of this community servicepractice is located at the Sugar Ants SMEs located in Way Kalam village.Here I will focus on the use of social media for digital marketing to improve marketing and also make ant sugar products forthe Haris Pratama Ants Sugar SMEs.As well as participating in village activities, including: road repair work, mutual cooperation, helping the Way Kalam village tourism awareness group,measuring and mapping village land assets and holding a farewell event at the village hall

Additional records of parasitic Camponotus Mayr (Hymenoptera: Formicidae) species from Turkey with queen description of Camponotus ruseni Karaman, 2012

The genus Camponotus Mayr is the second speciose ant genus after Pheidole Westwood and includes two parasitic species, Camponotus ruseni Karaman and C. universitatis Forel which are known only from Turkey to co-exist. We present new records with some biological notes of this parasitic species from Turkey and describe the hitherto unknown queen of C. ruseni. Also, the parasitism status of C. ruseni is discussed.

Practical meliponiculture: use of trap boxes to control Tracuá Carpenter ants (Camponotus atriceps Smith, 1858), an important natural enemy

This study aimed to observe the attractiveness efficiency of trap boxes installed in collective shelters of stingless bee colonies (Melipona flavolineata, Melipona fasciculata and Scaptotrigona aff. depilis), as an alternative method for non-chemical control of tracuá carpenter ants (Camponotus atriceps). The study was conducted at Embrapa Amazônia Oriental, in Belém, Pará, Brazil, from March to August 2015. The results showed that the efficiency of this technique depended on the presence of bee colonies and on the bee species in the collective shelter. Overall, an efficiency of 40.6% was found in the capture of C. atriceps individuals, which rose to 75% considering only collective shelters of M. fasciculata colonies, and to 87.5% for collective shelters of M. flavolineata. Trap boxes installed in collective shelters of S. depilis did not attract any C. atriceps group or individuals. The use of trap boxes in collective shelters of stingless bee colonies of the genus Melipona (M. flavolineata and M. fasciculata) is an efficient alternative method of non-chemical control of tracuá carpenter ants (C. atriceps).

A taxonomic revision of the Malagasy endemic subgenus Mayria of the genus Camponotus (Hymenoptera, Formicidae) based on qualitative morphology and quantitative morphometric analyses.

The subgenus Mayria of the genus Camponotus (Hymenoptera: Formicidae) is revised. The subgenus is endemic to Madagascar where it occupies a broad range of habitats, from deciduous and dry forest to rainforest. A taxonomic review is provided of this subgenus, integrating multiples lines of evidence including qualitative morphology and quantitative morphometry. Species hypotheses are formed by Nest Centroid clustering. In total, 36 species are treated, of which eleven are newly described: Camponotusandrianjakasp. nov., Camponotusantsaraingysp. nov., Camponotuschrislainisp. nov., Camponotusclaverisp. nov., Camponotusivadiasp. nov., Camponotusjjacquiasp. nov., Camponotusmaintilanysp. nov., Camponotusnorvigisp. nov., Camponotusihazofotsysp. nov., Camponotustsimelahysp. nov., Camponotuszorosp. nov. Five species are redescribed. Camponotusthemistocles Forel stat. nov., is raised to species. In addition, the subgenus is redefined to include 39 species. Twenty-two previously described species are transferred to this subgenus and thirteen species previously placed in the subgenus are transferred out of the subgenus. Nine morphologically consistent species groups are delineated to facilitate species identification within the subgenus. This revision includes a classification, a key to species groups, and an updated key to species based on the minor worker caste.

Time-course RNASeq of Camponotus floridanus forager and nurse ant brains indicate links between plasticity in the biological clock and behavioral division of labor

BackgroundCircadian clocks allow organisms to anticipate daily fluctuations in their environment by driving rhythms in physiology and behavior. Inter-organismal differences in daily rhythms, called chronotypes, exist and can shift with age. In ants, age, caste-related behavior and chronotype appear to be linked. Brood-tending nurse ants are usually younger individuals and show “around-the-clock” activity. With age or in the absence of brood, nurses transition into foraging ants that show daily rhythms in activity. Ants can adaptively shift between these behavioral castes and caste-associated chronotypes depending on social context. We investigated how changes in daily gene expression could be contributing to such behavioral plasticity in Camponotus floridanus carpenter ants by combining time-course behavioral assays and RNA-Sequencing of forager and nurse brains.ResultsWe found that nurse brains have three times fewer 24 h oscillating genes than foragers. However, several hundred genes that oscillated every 24 h in forager brains showed robust 8 h oscillations in nurses, including the core clock genes Period and Shaggy. These differentially rhythmic genes consisted of several components of the circadian entrainment and output pathway, including genes said to be involved in regulating insect locomotory behavior. We also found that Vitellogenin, known to regulate division of labor in social insects, showed robust 24 h oscillations in nurse brains but not in foragers. Finally, we found significant overlap between genes differentially expressed between the two ant castes and genes that show ultradian rhythms in daily expression.ConclusionThis study provides a first look at the chronobiological differences in gene expression between forager and nurse ant brains. This endeavor allowed us to identify a putative molecular mechanism underlying plastic timekeeping: several components of the ant circadian clock and its output can seemingly oscillate at different harmonics of the circadian rhythm. We propose that such chronobiological plasticity has evolved to allow for distinct regulatory networks that underlie behavioral castes, while supporting swift caste transitions in response to colony demands. Behavioral division of labor is common among social insects. The links between chronobiological and behavioral plasticity that we found in C. floridanus, thus, likely represent a more general phenomenon that warrants further investigation.

Diversity and Distribution of Ants (Hymenoptera: Formicidae) in Sunderbans, West Bengal, India

The present study deals with the biodiversity of ants in Indian Sunderbans. Study locations were selected from reclaimed area of eastern, central and western sector of Indian Sunderbans. Ants were collected randomly during pre-monsoon and post-monsoon period from different habitats of selected locations likely homestead orchard, paddy field, sandy beach, mangrove patch and waste land by using honey bait and hand picking method. Altogether 62 species of ants under 30 genera and 5 subfamilies were identified from the inhabited areas of Sunderbans. The present study revealed that the predominant subfamily was the Myrmicinae with 12 genera and 28 species followed by Formicinae, Ponerinae and Dolichoderinae. The genus Camponotus was found to be the most speciose genus in all the studied locations. Total 4 genera namely Camponotus, Pheidole, Lepisiota and Crematogaster were common in all the six habitats. The species richness of ant communities in the mangrove habitat was found relatively poor than agricultural land and homestead orchard. The ant genera Monomorium, Camponotus, Pheidole, Crematogaster, Paratrechina, Lepisiota, Tapinoma, Diacamma, Nylanderia, Tetramorium, Pseudoneoponera, Trichomyrmex, Iridomyrmex, Solenopsis, Carebara, Dolichoderus, Dilobocondyla, Leptogenys, Oecophylla, Cataulacus and Tetraponera were found in both pre- and post-monsoon seasons. Shannon diversity index and Simpson diversity index values indicated that the ant community is mature and stable in studied locations of Sunderbans.

Positive Eusocial Impacts on Ants by Taurine Derivatives.

The present study is to investigate potential eusocial effects on ants from treatment of taurine or its derivatives: galactose-taurine (GT) or xylose-taurine (XT). Japanese carpenter ants (Camponotus japonicus) were maintained on taurine-supplemented diets, and their performance was evaluated according to arbitrary eusocial indexes. Four classes of criteria were employed: establishment of residence chambers, survival at severe conditions, cooperative defense index (CDI), and population size. Taurine or its derivatives were administered orally in 0.1mM sucrose solution. When fed with taurine or taurine derivatives, ants built more chambers than the non-fed control. Among the taurine groups, the XT-fed group showed the highest number of chambers. Differences in survivorship were obvious between the control and taurine-fed groups at the extreme conditions of light exposure and high temperature. More ants survived when fed with taurine or its derivatives. The taurine-supplemented groups took less time to organize a defense form than the control. The XT-fed group showed a high level of CDI which refer to the willingness to participate in defense against a foreign queen. The taurine-fed group sustained higher total numbers of ants. The XT-fed groups showed a 15% increase in the number of workers and an 11% increase in the number of eggs. The taurine-fed ants positively responded according to the eusocial vitality indexes, especially when fed with XT. In summary, these results show that ants respond more like superorganisms when treated with XT among taurine or its two derivatives.

Жесткокрылые (Coleoptera) в гнездах мухоловки-пеструшки Ficedula hypoleuca (Pallas, 1764) на юго-востоке Приладожья (Республика Карелия)

Invertebrates collected in the Republic of Karelia in 2016 from nests of the pied flycatcher Ficedula hypoleuca (Pallas, 1764) are analyzed and 516 specimens of invertebrates are identified. The vast majority of these invertebrates are Hymenoptera (ants of the genus Camponotus) – 46.6% and various beetles (Coleoptera) – 46.37%. An annotated list of 38 species of beetle from 22 families is presented. The beetle fauna of the studied European pied flycatcher nests is mixed and includes both nidicolous species and free-living species that are not directly related to nest microcenoses. The rare beetles species Melandrya dubia (Schaller, 1783) and Otho sphondyloides (Germar, 1818), were found.

Production, characterization and pesticidal potential of Bacillus species metabolites against sugar ant (Camponotus consobrinus)

The use of biopesticides in pest management and pre-harvest disease and crop pest control have been advocated in recent years. This is because of their eco-friendliness and suitability for pest control in the agricultural industry. The objective of this study was to determine the antibacterial and pesticidal potential against sugar ant of metabolites produced by Bacillus species. The species were B. proteolyticus, B. thuringensis, B. cereus and B. subtilis. Metabolite production was carried out in batch experimental setup. The inoculated flasks were incubated in an incubator shaker for 120 h at temperature of 37 °C ± 2 °C. Metabolite extraction was carried out using the acid precipitation method. The crude metabolites were characterized using Fourier Transform Infrared (FTIR) and Gas Chromatography Mass Spectroscopy (GC-MS). Antibacterial activity of the metabolites was carried out both in agar and broth media while pesticidal potential was carried out using the diet-fed approach. All the metabolites showed antibacterial activity against the test pathogens used for investigation. This was irrespective of whether they were used singly or in combination. Generally, the rate of kill of the sugar ants by the respective metabolites was directly proportional to metabolite concentration in the diet. In the control diet setup with no added metabolite, no mortality was recorded throughout the period of incubation. The study findings gave an indication of the potential of these metabolites for possible control of phytopathogens.

Educational Background and Gender Factors Affecting Sales Turnover of SMEs Sugar Ants Entrepreneur

The purpose of this study was to determine the influence of educational background and gender on the sales turnover of UKM Sugar Ant Entrepreneurs. The method used is SEM PLS 3 with a population of 50 respondents of SMEs Sugar Ant Entrepreneurs. The results of the study found that educational background had a positive effect on sales turnover of SMEs Sugar Ant Entrepreneurs, while gender did not have a positive effect on sales turnover of SMEs Sugar Ants Entrepreneurs. So, the Sugar Ant Entrepreneurs who are in Lebak Banten in obtaining sales turnover are not determined by gender itself, but are determined by educational background

Formic acid modulates latency and accuracy of nestmate recognition in carpenter ants.

Decision-making processes face the dilemma of being accurate or faster, a phenomenon that has been described as speed-accuracy trade-off in numerous studies on animal behaviour. In social insects, discriminating between colony members and aliens is subject to this trade-off as rapid and accurate rejection of enemies is of primary importance for the maintenance and ecological success of insect societies. Recognition cues distinguishing aliens from nestmates are embedded in the cuticular hydrocarbon (CHC) layer and vary among colonies. In walking carpenter ants, exposure to formic acid (FA), an alarm pheromone, improves the accuracy of nestmate recognition by decreasing both alien acceptance and nestmate rejection. Here, we studied the effect of FA exposure on the spontaneous aggressive mandible opening response (MOR) of harnessed Camponotus aethiops ants presented with either nestmate or alien CHCs. FA modulated both MOR accuracy and the latency to respond to odours of conspecifics. In particular, FA decreased the MOR towards nestmates but increased it towards aliens. Furthermore, FA decreased MOR latency towards aliens but not towards nestmates. As response latency can be used as a proxy of response speed, we conclude that contrary to the prediction of the speed-accuracy trade-off theory, ants did not trade off speed against accuracy in the process of nestmate recognition.

Inhibition of serotonergic signaling induces higher consumption of both sucrose solution and toxic baits in carpenter ants

Biogenic amines play an important role in the regulation of appetitive responses in insects. Among them, serotonin (5-HT) regulates feeding-related processes in numerous insect species. In carpenter ants, 5-HT administration has been shown to depress feeding behavior, thus opening the possibility of using 5-HT modulation in control strategies against those species considered as pest. Here we studied if administration of a 5-HT antagonist, ketanserin, promotes feeding of a sucrose solution and a toxic bait in carpenter ants Camponotus mus. We found that 3 h after a single oral administration of ketanserin, the mass of sucrose solution consumed by carpenter ants increased significantly. A similar effect was found after a chronic administration that lasted 5 days. Yet, ketanserin did neither affect the intake rates nor the activity of the pharyngeal pump that mediates feeding dynamics. In addition, ketanserin promoted the consumption of a toxic bait based on boric acid. Our results thus show that feeding motivation and consumption of both sucrose solution and a toxic bait can be enhanced via prior administration of ketanserin. We discuss the possible mechanisms underlying these effects and conclude that understanding basic physiological and neural principles that underlie feeding motivation allows establishing more efficient control strategies for pest insects.

Leaf litter and rock bag surveys allow for detection and DNA barcoding characterization of diet composition of dusky salamanders

Salamanders are vital components of many aquatic ecosystems food webs and are often found in diverse habitats, including both urban and semi-rural environments. The northern dusky salamander, Desmognathus fuscus is a common salamander found throughout the southeastern United States and is an important predator of aquatic macroinvertebrates. However, very little is known about either diet or suitable survey techniques for this species in human altered habitats, which may vary based on level of urbanization (e.g., are either spring-fed, derived from ponds, modified ditches, etc.). Therefore, we used multiple survey methods (leaf litter bags, novel rock bags, and quadrat sampling) to quantify relative abundance of D. fuscus on Wingate University's campus, in Wingate, North Carolina. We also collected and identified aquatic invertebrates from bag sampling and diet items obtained from gastric lavage of adult salamanders from quadrat sampling. Leaf litter bags contained the highest relative abundance of salamanders (47) compared to rock bags (14), with quadrat sampling yielding primarily adult salamanders. We noted a significant difference among our two sites sampled in salamander relative abundance (Man-Whitney U test = 67.5, p < 0.001), possibly due to reduced water quality, canopy cover, or less available habitat. Aquatic worms represented the most frequent potential food item sampled from both bag types (61.9%), followed by Diptera nymphs (13.7%). Potential food items from leaf and rock bags as well as gastric lavage samples collected from Desmognathus were further identified using DNA barcoding. These food items included a variety of both aquatic and terrestrial invertebrates (annelid worms, springtails, chironomids, carpenter ants, shore flies, wasps, and wood lice). These results indicate urban salamanders may forage both in the stream and in the riparian zone or advantageously consume insects which fall into the stream. This study adds to our body of knowledge on the ecology of salamanders in urban stream environments.

Antenna Cleaning Is Essential for Precise Behavioral Response to Alarm Pheromone and Nestmate-Non-Nestmate Discrimination in Japanese Carpenter Ants (Camponotus japonicus).

Simple SummaryGrooming is a common behavior in animals. It serves the function of removing foreign materials and excessive amounts of self-secreted materials from the body’s surface. Social insects, such as honeybees or ants, use various types of pheromones, some of which propagate information about the environment to conspecific individuals, for chemical communication. The individuals that receive such information can respond with suitable behaviors to protect themselves and their society. Hence, grooming is important for the maintenance of the correct performance of their sensory organs on antennae for pheromone perception. Here, we experimentally limited self-grooming of the antennae in workers of the Japanese carpenter ant (Camponotus japonicus) by removing a pair of antennal cleaning apparatuses from the forelegs and investigated their behavioral change in response to exposure to the alarm pheromone or to encounters with nestmates or non-nestmates. Comparisons between self-grooming-nonlimited and self-grooming-limited ants showed that the self-grooming-limited ants gradually exhibited decreased locomotion activity in their fight-or-flight response to the alarm pheromone and experienced increased failure in nestmate and non-nestmate discrimination. Thus, the results of the present study suggest that antennal sensory system maintenance supports social communication, which is indispensable not only to the individual workers but also to the survival of their society.Self-grooming of the antennae is frequently observed in ants. This antennal maintenance behavior is presumed to be essential for effective chemical communication but, to our knowledge, this has not yet been well studied. When we removed the antenna-cleaning apparatuses of the Japanese carpenter ant (C. japonicus) to limit the self-grooming of the antennae, the worker ants demonstrated the self-grooming gesture as usual, but the antennal surface could not be sufficiently cleaned. By using scanning electron microscopy with NanoSuit, we observed the ants’ antennae for up to 48 h and found that the antennal surfaces gradually became covered with self-secreted surface material. Concurrently, the self-grooming-limited workers gradually lost their behavioral responsiveness to undecane—the alarm pheromone. Indeed, their locomotive response to the alarm pheromone diminished for up to 24 h after the antenna cleaner removal operation. In addition, the self-grooming-limited workers exhibited less frequent aggressive behavior toward non-nestmate workers, and 36 h after the operation, approximately half of the encountered non-nestmate workers were accepted as nestmates. These results suggest that the antennal sensing system is affected by excess surface material; hence, their proper function is prevented until they are cleaned.

Co-occurrence in ant primary parasitoids: a Camponotus rectangularis colony as host of two eucharitid wasp genera.

Different assemblages of parasitoids may attack a given host species and non-random distribution patterns in parasitoid species assemblages have been reported on various occasions, resulting in co-occurrence at the population, colony, or even individual host levels. This is the case for different closely related species of eucharitid wasps (a family of specialized ant parasitoids) sharing similar niches and co-occurring on the same host at different levels. Here we reviewed all known associations between eucharitid wasps and the ant host genus Camponotus Mayr, 1861 and reported new ant-parasitoid associations. In addition, we report a new case of co-occurrence in eucharitid wasps, at the host colony level, involving a new undescribed species of Pseudochalcura Ashmead, 1904 and an unidentified species of Obeza Heraty, 1985, which attack the common but very poorly known neotropical arboreal ant Camponotus rectangularis Emery, 1890. Most attacks were solitary, but various cocoons were parasitized by two (16%) or three (8%) parasitoids. Globally, parasitism prevalence was very low (3.7%) but showed an important variability among samples. Low parasitism prevalence along with host exposure to parasitoid attack on host plants and overlapping reproductive periods of both parasitoid species may have allowed the evolution of co-occurrence. We also provided some additional data regarding the host ant nesting habits, the colony composition and new symbiotic associations with membracids and pseudococcids. The seemingly polydomous nesting habits of C. rectangularis could play a part in the reduction of parasitism pressure at the population level and, combined with occasionally important local parasitism rates, could also contribute to some parts of the colonies escaping from parasites, polydomy possibly representing an effective parasitism avoidance trait.

Taxonomic notes on rattan-inhabiting ants of the genus Camponotus (Hymenoptera: Formicidae)

Camponotus megalonyx Wheeler, 1919 is an ant species nesting in rattan and represents the single member of the subgenus Myrmopalpella Stärcke, 1934. Camponotus (Tanaemyrmex) dracocephalus Stitz, 1938, syn. nov., described from a queen with a strangely shaped head is synonymised with C. mega­lonyx, based on the comparison of a queen from Sabah (Borneo), associated with a worker of C. megalonyx, with the images of the holotype of C. dracocephalus. Comparison of the type of C. dracocephalus with queens of other species from the subgenus Tanaemyrmex Ashmead, 1905 clearly confirms that this species should be excluded from the subgenus. Relationship of the species of the subgenus Myrmoplatys Forel, 1916, also inhabitants of rattans, with C. (Myrmopalpella) megalonyx is briefly discussed. Based on a number of characters of the worker and queen, C. (Myrmoplatys) korthalsiae concilians Forel, 1915 is upgraded to specific rank. An illustrated redescription of C. concilians stat. promotus is given.

All sugars ain't sweet: selection of particular mono-, di- and trisaccharides by western carpenter ants and European fire ants.

Ants select sustained carbohydrate resources, such as aphid honeydew, based on many factors including sugar type, volume and concentration. We tested the hypotheses (H1–H3) that western carpenter ants, Camponotus modoc, seek honeydew excretions from Cinara splendens aphids based solely on the presence of sugar constituents (H1), prefer sugar solutions containing aphid-specific sugars (H2) and preferentially seek sugar solutions with higher sugar content (H3). We further tested the hypothesis (H4) that workers of both Ca. modoc and European fire ants, Myrmica rubra, selectively consume particular mono-, di- and trisaccharides. In choice bioassays with entire ant colonies, sugar constituents in honeydew (but not aphid-specific sugar) as well as sugar concentration affected foraging decisions by Ca. modoc. Both Ca. modoc and M. rubra foragers preferred fructose to other monosaccharides (xylose, glucose) and sucrose to other disaccharides (maltose, melibiose, trehalose). Conversely, when offered a choice between the aphid-specific trisaccharides raffinose and melezitose, Ca. modoc and M. rubra favoured raffinose and melezitose, respectively. Testing the favourite mono-, di- and trisaccharide head-to-head, both ant species favoured sucrose. While both sugar type and sugar concentration are the ultimate cause for consumption by foraging ants, strong recruitment of nest-mates to superior sources is probably the major proximate cause.

Allocordyceps baltica gen. et sp. nov. (Hypocreales: Clavicipitaceae), an ancient fungal parasite of an ant in Baltic amber

An ancient fungal parasite of a Camponotus ant (Formicidae: Hymenoptera) in Baltic amber is described as Allocordyceps baltica gen. et sp. nov. (Hypocreales: Clavicipitaceae). The new genus is characterized by an orange, stalked, cup-shaped ascoma with partially immersed perithecia that emerges from the rectum of the ant, two separate stromata with septate mycelium that emerge from the base of the neck and the abdomen of the ant, respectively, and free-standing putative perithecia bearing putative asci with putative multicellular ascospores fragmented into one-celled partspores. This oldest known fossil fungus of an ant could represent a precursor of the genus Ophiocordyceps, which at present is the only fungal lineage parasitizing ants of the genus Camponotus. The fossil shows unique morphological features that existed in the Hypocreales some 35–55 MYA.

Quantitative cognition in carpenter ants

Processing information about quantities allows animals to make optimal decisions during many natural contexts, such as foraging, territorial defense, offspring care, mate choice, and intra-sexual competition. Compared to the wealth of information available in vertebrates, much less is known in invertebrates, even though the processing of quantities is equally relevant for both taxa. Here, we used two separate ecologically relevant tasks (brood pile preference and landmark-guided foraging) to investigate two dimensions of quantitative cognition in carpenter ants: spontaneous quantitative judgments and trained use of sequential landmarks. Individual ants spontaneously discriminated between two piles of dummy cocoons both when the choice involved smaller (1 vs. 2, 3, 4) and larger numerical contrasts (2 vs. 4, 6, 8). Ants used both chemical and visual/tactile cues and their performance was dependent on the numerical ratio. In the second task, ants preferentially searched near the trained landmark (out of five identical ones) despite alterations in its position, suggesting that they used ordinal information about its location when searching for food. In this experiment, ants showed a limit at four since their performance drastically decreased when they were trained to the 5th landmark. We showed that carpenter ants use both relative quantity and relative position to make efficient decisions. Our study contributes to the scant body of knowledge available on quantitative cognition in invertebrate species. There is ample experimental evidence that non-human animals are able to process quantitative information, in particular mammals, some birds, and fish, and that this ability is useful in a variety of ecologically relevant situations. Yet, information about quantitative cognition in invertebrates is very scarce. We show that individual ants are able to use both relative quantity and relative position of items. Nurse ants spontaneously discriminated between two brood piles of different sizes and foragers were able to learn to identify a landmark associated with food on the basis of its position in a series of identical ones. These results suggest that ants might use quantitative information to make optimal choices in their natural environment although the precise mechanisms underlying this ability should be further investigated.

Know your foe: synanthropic spiders are deterred by semiochemicals of European fire ants.

Many ants prey on spiders, suggesting that web-building spiders may avoid micro-locations near ant colonies or frequented by foraging ants. Here we tested the hypothesis that ant-derived semiochemicals deter synanthropic spiders. To generate stimuli, we exposed filter paper for 12 h to workers of European fire ants, Myrmica rubra, black garden ants, Lasius niger, or western carpenter ants, Camponotus modoc, and then offered select urban spiders in three-chamber olfactometer bioassays a choice between ant-exposed filter paper and unexposed control filter paper. Semiochemical deposits of M. rubra, but not of L. niger or C. modoc, had a significant deterrent effect on subadults of the false black widow, Steatoda grossa, the black widow, Latrodectus hesperus, and the hobo spider, Eratigena agrestis, as well as a moderate (but statistically not significant) deterrent effect on the cross spider, Araneus diadematus. The deterrent effect caused by semiochemical deposits of M. rubra may be attributable to the aggressive nature and efficient foraging of M. rubra in its invaded North American range, exerting selection pressure on community members to recognize M. rubra semiochemicals and to avoid micro-locations occupied by M. rubra.