ants and Ectoparasitic-Infestations

Mutualisms between honeydew-producing insects and ants change the emission of volatiles from plants, but whether such changes alter the behaviors of ants that tend honeydew-producing insects or wasps that parasitize honeydew-producing insects remain unknown. This study compared the behavioral responses of the ant Tetramorium bicarinatum and the parasitoid wasp Aenasius bambawalei to odors from cotton plants infested with the mealybug Phenacoccus solenopsis or infested with the mealybug and the ant, which tends the mealybug. The ant could not distinguish between the volatiles from plants infested with the mealybug alone and those from plants infested with the mealybug and the ant. Likewise, naïve wasps failed to distinguish between volatiles from the two treatments. In contrast, experienced wasps preferred volatiles from plants infested with the mealybug and the ant. Volatile analysis showed that the amounts of MeSA were increased and those of methyl nicotinate were decreased when plants were infested by the mealybug and the ant rather than when plants were uninfested or were infested by the mealybug alone. Thus, the mutualism between the mealybug and ant changed the volatiles emitted by cotton plants such that the attraction of A. bambawalei (but not that of the ant) to the plants was increased.

Topics: Animals; Ants; Ectoparasitic Infestations; Feeding Behavior; Host-Parasite Interactions; Plants; Symbiosis; Volatile Organic Compounds; Wasps

Predation can regulate populations and strongly affect invasion success of novel prey. The deer ked (Lipoptena cervi; Linnaeus 1758) is an invasive ectoparasite of cervids that spends a long period of its life cycle outside the host. Prior to this study, virtually nothing was known about natural summer time predation on the deer ked. We aimed to evaluate the magnitude of summer time predation on L. cervi pupae in different habitats and to identify potential predators. We conducted a set of field experiments, where we exposed L. cervi pupae to various ground-dwelling vertebrate and invertebrate predators. The loss of pupae was monitored for different predator guilds. Three habitats of the moose, the main host species, were studied: (1) moist heath forest; (2) dry, logged heath forest; and (3) moist meadow. The results indicate notable summer time predation on L. cervi pupae, and the pupal predation varied within and between habitats, being lowest in the meadow habitat. We found a positive correlation between pupal loss and abundance of the common lizard (Zootoca vivipara), harvestmen (Opiliones), ground spiders (Gnaphosidae) and Formicinae-ants. We conclude that summer time predation during the pupal phase can have a notable local importance for the L. cervi abundance.

Topics: Animals; Ants; Deer; Diptera; Ectoparasitic Infestations; Lizards; Predatory Behavior; Pupa; Seasons; Spiders

Determination of the number of founders responsible for the establishment of invasive populations is important for developing biologically based management practices, predicting the invasive potential of species, and making inferences about ecological and evolutionary processes. The fire ant Solenopsis invicta is a major invasive pest insect first introduced into the USA from its native South American range in the mid-1930s. We use data from diverse genetic markers surveyed in the source population and the USA to estimate the number of founders of this introduced population. Data from different classes of nuclear markers (microsatellites, allozymes, sex-determination locus) and mitochondrial DNA are largely congruent in suggesting that 9-20 unrelated mated queens comprised the initial founder group to colonize the USA at Mobile, Alabama. Estimates of founder group size based on expanded samples from throughout the southern USA were marginally higher than this, consistent with the hypothesis of one or more secondary introductions of the ant into the USA. The rapid spread and massive population build-up of introduced S. invicta occurred despite the loss of substantial genetic variation associated with the relatively small invasive propagule size, a pattern especially surprising in light of the substantial genetic load imposed by the loss of variation at the sex-determination locus.

Topics: Animals; Ants; Base Sequence; Computer Simulation; DNA, Mitochondrial; Ectoparasitic Infestations; Enzymes; Female; Genetic Variation; Haplotypes; Microsatellite Repeats; Molecular Sequence Data; Sequence Analysis, DNA; Southeastern United States

A 32-year-old woman presented with an abrupt, localized loss of scalp hair that occurred on the previous day. Her nails, skin, and mucosae were normal. On the vertex of the scalp, there was a circular patch of alopecia; the hairs were broken at approximately equal lengths above the skin surface. Several erythematous macules were seen in the affected area, but scale, twisted hair, and exclamation-mark hairs were not present. Further examination revealed the presence of ants on the scalp. This patient is one of several referred to our department presenting with hair loss associated with hair-cutter ant invasion.

Topics: Adult; Alopecia; Animals; Ants; Ectoparasitic Infestations; Female; Humans; Scalp

Localized hair shedding caused by Pheidole ants is reported as a newly recognized type of hair loss, mimicking alopecia areata. We report two cases from Kerman, Iran. This sudden hair loss demonstrates that ants such as the Pheidole dimorphic species can cause hair shedding. Fairly clean cutting of the scalp hair takes place just a few micrometers above the skin surface and simulates alopecia areata or mechanical shaving of scalp hair. This infestation has not been reported from other countries, and this report is the second from Iran.

Topics: Adolescent; Adult; Alopecia Areata; Animals; Ants; Ectoparasitic Infestations; Female; Humans; Male; Scalp