Diversity of bacterial endosymbionts and bacteria–host co‐evolution in Gondwanan relict moss bugs (Hemiptera: Coleorrhyncha: Peloridiidae)

Abstract

Many hemipterans are associated with symbiotic bacteria, which are usually found intracellularly in specific bacteriomes. In this study, we provide the first molecular identification of the bacteriome-associated, obligate endosymbiont in a Gondwanan relict insect taxon, the moss bugs (Hemiptera: Coleorrhyncha: Peloridiidae), which represents one of the oldest lineages within the Hemiptera. Endosymbiotic associations of fifteen species of the family were analysed, covering representatives from South America, Australia/Tasmania and New Zealand. Phylogenetic analysis based on four kilobases of 16S-23S rRNA gene fragments showed that the obligate endosymbiont of Peloridiidae constitute a so far unknown group of Gammaproteobacteria which is named here 'Candidatus Evansia muelleri'. They are related to the sternorrhynchous endosymbionts Candidatus Portiera and Candidatus Carsonella. Comparison of the primary-endosymbiont and host (COI + 28S rRNA) trees showed overall congruence indicating co-speciation the hosts and their symbionts. The distribution of the endosymbiont within the insect body and its transmission was studied using FISH. The endosymbionts were detected endocellularly in a pair of bacteriomes as well as in the 'symbiont ball' of the posterior pole of each developing oocyte. Furthermore, ultrastructural analysis of the Malpighian tubules revealed that most host nuclei are infected by an endosymbiotic, intranuclear bacterium that was determined as an Alphaproteobacterium of the genus Rickettsia.

Endosymbiotic microorganisms of aphids (Hemiptera: Sternorrhyncha: Aphidoidea): Ultrastructure, distribution and transovarial transmission

“…in the ovaries of the mother) (see e.g. Buchner, 1965;Szklarzewicz & Moskal, 2001;Szklarzewicz et al, 2006Szklarzewicz et al, , 2010Szklarzewicz et al, , 2013Sacchi et al, 2008;Kuechler et al, 2012Kuechler et al, , 2013Swiatoniowska et al, 2013 for further details). Both the histological studies of Buchner (1965Buchner ( , 1966Buchner ( , 1967) and more recent ultrastructural studies (Cheng & Hou, 2001;Szklarzewicz & Moskal, 2001;Szklarzewicz et al, 2006Szklarzewicz et al, , 2010Szklarzewicz et al, , 2013Sacchi et al, 2008;Kuechler et al, 2011Kuechler et al, , 2012Koga et al, 2012;Matsuura et al, 2012;Swiatoniowska et al, 2013) have revealed that the latter transmission of endosymbionts (termed transovarial transmission) may differ even in closely related groups of hemipterans.…”

Heritable symbiosis: The advantages and perils of an evolutionary rabbit hole

“…The diversity and abundance of insects feeding on xylem or phloem sap reflect the dominance of vascular plants in terrestrial ecosystems: symbionts provided the entry to a vast and expanding new niche that spread across the globe. As a counterexample, the Coleorrhyncha, which resembles other sap-feeding groups in originating around the same time (the Permian) and having an obligate symbiont, contains only about 24 species, reflecting ties to specific nonvascular plants (certain mosses) (13,14).…”

Pharmaceuticals and personal care products alter the holobiome and development of a medically important mosquito

“…Once they reach the fourth instar, larvae cease feeding and prepare to molt into a non-feeding pupal stage. Mosquitoes, like many insects, rely on endosymbionts (microorganisms which provide nutrients or other beneficial functions) to grow and develop (Chouaia et al, 2012;Clark et al, 2010;Kafil et al, 2013;Kuechler et al, 2013;Moran et al, 2005b). For example, bacteria in the genus Buchnera are commonly endosymbionts of aphids and provide the aphid with essential amino acids (Douglas, 1998).…”