title: Large scale patterns of abundance and distribution of parasites in Mexican bumblebees.
abstract: Bumblebees are highly valued for their pollination services in natural ecosystems as well as for agricultural crops. These precious pollinators are known to be declining worldwide, and one major factor contributing to this decline are infections by parasites. Knowledge about parasites in wild bumblebee populations is thus of paramount importance for conservation purposes. We here report the geographical distribution of Crithidia and Nosema, two common parasites of bumblebees, in a yet poorly investigated country: Mexico. Based on sequence divergence of the Cytochrome b and Glycosomal glyceraldehyde phosphate deshydrogenase (gGPDAH) genes, we discovered the presence of a new Crithidia species, which is mainly distributed in the southern half of the country. It is placed by Bayesian inference as a sister species to C. bombi. We suggest the name Crithidia mexicana for this newly discovered organism. A population of C. expoeki was encountered concentrated on the flanks of the dormant volcanic mountain, Iztaccihuatl, and microsatellite data showed evidence of a bottleneck in this population. This study is the first to provide a large-scale insight into the health status of endemic bumblebees in Mexico, based on a large sample size (n=3,285 bees examined) over a variety of host species and habitats.
authors.affiliation: Institute of Integrative Biology (IBZ), ETH Zürich, Universitätsstrasse 16, CH-8092 Zürich, Switzerland. Electronic address: marie.gallot@gmail.com.
authors.forename: Marie
authors.initials: M
authors.lastname: Gallot-Lavallée
authors.affiliation: Institute of Integrative Biology (IBZ), ETH Zürich, Universitätsstrasse 16, CH-8092 Zürich, Switzerland.
authors.forename: Regula
authors.initials: R
authors.lastname: Schmid-Hempel
authors.affiliation: Departamento de Agricultura, Sociedad y Ambiente, El Colegio de la Frontera Sur, San Cristóbal de Las Casas, Chiapas, Mexico.
authors.forename: Rémy
authors.initials: R
authors.lastname: Vandame
authors.affiliation: Departamento de Ciencias Químico Biológicas, Universidad de las Américas Puebla, Mexico.
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Vergara
authors.affiliation: Institute of Integrative Biology (IBZ), ETH Zürich, Universitätsstrasse 16, CH-8092 Zürich, Switzerland.
authors.forename: Paul
authors.initials: P
authors.lastname: Schmid-Hempel
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D001516:Bees / Q000469:parasitology*; D003247:Conservation of Natural Resources; D003421:Crithidia / Q000235:genetics / Q000502:physiology*; D016054:DNA, Protozoan / Q000737:chemistry; D058507:Host Specificity; D006790:Host-Parasite Interactions; D008800:Mexico; D018895:Microsatellite Repeats; D016818:Nosema / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D011156:Population Density
chemical_list: D016054:DNA, Protozoan
keywords: Crithidia mexicana; Mexico; Nosema; Parasite; Trypanosome; Wild bumblebee