Genetic and morphological variation of bee-parasitic Tropilaelaps mites (Acari: Laelapidae): new and re-defined species

Abstract

Mites in the genus Tropilaelaps are parasites of social honeybees. Two species, Tropilaelaps clareae and T. koenigerum, have been recorded and their primary hosts are presumed to be the giant honeybees of Asia, Apis dorsata and A. laboriosa. The most common species, T. clareae, is also an economically important pest of the introduced Western honeybee (A. mellifera) throughout Asia and is considered an emerging threat to world apiculture. In the studies reported here, genetic (mtDNA CO-I and nuclear ITS1-5.8S-ITS2 gene sequence) and morphological variation and host associations were examined among Tropilaelaps isolates collected from A. dorsata, A. laboriosa and A. mellifera throughout Asia and neighbouring regions. The results clearly indicate that the genus contains at least four species. Tropilaelaps clareae, previously assumed to be ubiquitous in Asia, was found to be two species, and it is here redefined as encompassing haplotypes (mites with distinct mtDNA gene sequences) that parasitise native A. dorsata breviligula and introduced A. mellifera in the Philippines and also native A. d. binghami on Sulawesi Island in Indonesia. Tropilaelaps mercedesae n. sp., which until now has been mistaken for T. clareae, encompasses haplotypes that, together with haplotypes of T. koenigerum, parasitise native A. d. dorsata in mainland Asia and Indonesia (except Sulawesi Island). It also parasitises introduced A. mellifera in these and surrounding regions and, with another new species, T. thaii n. sp., also parasitises A. laboriosa in mountainous Himalayan regions. Methods are described for identifying each species. These studies help to clarify the emerging threat of Tropilaelaps to world apiculture and will necessitate a revision of quarantine protocols for countries that import and export honeybees.

Prevalence and reproduction of Tropilaelaps mercedesae and Varroa destructor in concurrently infested Apis mellifera colonies

“…For example, the environmental conditions in Pakistan allow continuous rearing of brood and thus survival of Tropilaelaps (Waghchoure-Camphor and Martin 2009). According to these authors, T. clareae (likely referring to T. mercedesae based on species distribution reported by Anderson and Morgan 2007) infestations coincide with the increase in brood production (April to May). In our study, we found a negative correlation between the amount of brood and Tropilaelaps infestation, which corroborated the findings of Kavinseksan et al (2004)).…”

“…Although both V. destructor and T. mercedesae are observed in infesting colonies, T. mercedesae is considered to be a more serious problem of A. mellifera colonies than Varroa mites in Northern Thailand Anderson and Morgan 2007). This discrepancy in severity may be due to differences in their abilities to compete for honey bee hosts and reproduce within brood cells.…”

The ectoparasitic mite Tropilaelaps mercedesae (Acari, Laelapidae) as a vector of honeybee viruses

“…If this is the case, Tropilaelaps mites could also act as biological vectors similar to the other ectoparasitic mite V. destructor (Chen and Siede, 2007). Here we test this hypothesis by analyzing T. mercedesae (Anderson and Morgan, 2007) for the presence and replication of six honeybee viruses (KBV, SBV, CBPV, BQCV, ABPV, DWV).…”

“…The primary host of one of the better known species Tropilaelaps clareae is Apis dorsata (Laigo and Morse, 1968) but Tropilaelaps mites were able to switch to the western honeybee, Apis mellifera (Delfinado and Baker, 1961;Anderson and Morgan, 2007). Tropilaelaps clareae was first discovered on A. mellifera in the Philippines (Delfinado and Baker, 1961).…”

Changes in protein profile and RNA content of Apis mellifera worker pupa on parasitization with Tropilaelaps clareae

“…Tropilaelaps mites (Acari-Laelapidae) are ectoparasites of honeybees native to Asia (Delfinado and Baker, 1961;Laigo and Morse, 1968).The primary host of mite Tropilaelaps clareae is Apis dorsata (Laigo and Morse, 1968) but the mites also infested the western honey bee when the latter was introduced in India (Delfinado and Baker, 1961;Anderson and Morgan, 2007). Today mites (Acari) parasitizing honey bees have become a global problem.…”