Horizontal transmission of a microsporidium from the convergent lady beetle, Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae), to three coccinellid species of Nova Scotia

Evolutionary Relationships of “CandidatusRiesia spp.,” EndosymbioticEnterobacteriaceaeLiving within Hematophagous Primate Lice

“…While phoresy itself does not involve any humoral interaction between passenger (phoront) and carrier, in one case, a phoretic mite (Macrocheles subbadius) has been shown to feed on the hemolymph of its transporting host (Drosophila nigrospiracula) (30). The close association between the endosymbionts of lice and louse flies might be explained by horizontal transmission, which appears to be more common among microorganisms than previously thought (23,37). One might presume that the P-endosymbiont in lice is derived from the S-endosymbiont (i.e., increasing specialization over evolutionary time); however, this presents a hypothesis that can be tested directly in future studies.…”

Microsporidia Biological Control Agents and Pathogens of Beneficial Insects

“…hippodamiae prolongs the development of H. convergens larvae and reduces the fecundity and survival of adults. The pathogen is transmitted horizontally with 100% efficiency among H. convergens cohorts and other coccinellids when microsporidia-infected H. convergens eggs are cannibalized (Saito & Bjørnson 2006, 2008Joudrey & Bjørnson 2007). Under laboratory conditions, T. hippodamiae infects several coccinellids, including Adalia bipunctata (the two-spotted lady beetle), Coccinella septempunctata (seven-spotted lady beetle), C. trifasciata perplexa (three-banded lady beetle), and Harmonia axyridis (multicolored Asian lady beetle).…”

“…Under laboratory conditions, T. hippodamiae infects several coccinellids, including Adalia bipunctata (the two-spotted lady beetle), Coccinella septempunctata (seven-spotted lady beetle), C. trifasciata perplexa (three-banded lady beetle), and Harmonia axyridis (multicolored Asian lady beetle). For all of these beetle species, the development of T. hippodamiaeinfected larvae is prolonged when compared to uninfected larvae, but the pathogen has no effect on larval mortality (Saito & Bjørnson 2006, 2008.…”

Response to Comments on “Invasive Harlequin Ladybird Carries Biological Weapons Against Native Competitors”

“…However, several previous studies have already shown that horizontal transmission of microsporidia occurs among ladybird species through intraguild predation (10,11). Indeed, for this very reason, it is recommended that field-collected ladybirds should be controlled for the presence of microsporidia before being used for mass rearing and release in biological control programs (10). These data provide adequate evidence for horizontal transmission without considering more unlikely mechanisms such as cohibernation, which we would not advocate as a useful hypothesis for the reasons stated by de Jong et al Similarly, we see no similarity between the microsporidia we identified and the male-killing bacteria discussed by Sloggett: There is no indication that the microsporidia are endosymbiotic, and they are clearly maintained in an inactive state as spores in the hemolymph.…”

“…Sloggett compares this situation with the malekilling endosymbiotic bacteria in some ladybird species that are rarely transferred between individuals in the field, even within the same species. However, several previous studies have already shown that horizontal transmission of microsporidia occurs among ladybird species through intraguild predation (10,11). Indeed, for this very reason, it is recommended that field-collected ladybirds should be controlled for the presence of microsporidia before being used for mass rearing and release in biological control programs (10).…”