Sympatric lineages of inbreeding species provide an excellent opportunity to investigate species divergence patterns and processes. Many ambrosia beetle lineages (Curculionidae: Scolytinae) reproduce by predominant inbreeding through sib mating in nests excavated in woody plant parts wherein they cultivate symbiotic ambrosia fungi as their sole source of nutrition. The Xyleborini ambrosia beetle species Cnestus solidus and Cnestus pseudosolidus are sympatrically distributed across eastern Australia and have overlapping morphological variation. Using multilocus sequencing analysis of individuals collected from 19 sites spanning their sympatric distribution, we assessed their phylogenetic relationships, taxonomic status and microbial symbionts. We found no genetic differentiation between individuals morphologically identified as C. solidus and C. pseudosolidus confirming previous suggestions that C. pseudosolidus is synonymous to C. solidus. However, within C. solidus we unexpectedly discovered the sympatric coexistence of two morphologically indistinguishable but genetically distinct lineages with small nuclear yet large mitochondrial divergence. At all sites except one, individuals of both lineages carried the same primary fungal symbiont, a new Ambrosiella species, indicating that fungal symbiont differentiation may not be involved in lineage divergence. One strain of the maternally inherited bacterial endosymbiont Wolbachia was found at high prevalence in individuals of the more common lineage but not in the other, suggesting that it may influence host fitness. Our data suggest that the two Australian Cnestus lineages diverged allopatrically, and one lineage then acquired Wolbachia. Predominant inbreeding and Wolbachia infection may have reinforced reproductive barriers between these two lineages after their secondary contact contributing to their current sympatric distribution.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10798974 | PMC |
http://dx.doi.org/10.1038/s41437-023-00659-w | DOI Listing |
Sci Rep
December 2024
Laboratory of Fish Microbiology, Institute of Coastal Studies, Federal University of Para (UFPA), Alameda Leandro Ribeiro s/n, Braganca, 68600-000, Para, Brazil.
We evaluate the evidence of cryptic speciation in Larimus breviceps, a species widely distributed in the western South Atlantic, from the Greater Antilles to Santa Catarina in Brazil. Mitochondrial (COI, Cyt b, and Control Region) and nuclear (IGF1 and Tmo-4C4) sequences were obtained from populations in the western South Atlantic. The analysis revealed two genetically distinct, sympatric lineages with no gene flow, with L.
View Article and Find Full Text PDFNat Commun
December 2024
Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
The circumstances under which species diversify to genetically distinct lineages is a fundamental question in biology. Atlantic herring (Clupea harengus) is an extremely abundant zooplanktivorous species that is subdivided into multiple ecotypes that differ regarding spawning time and genetic adaption to local environmental conditions such as temperature, salinity, and light conditions. Here we show using whole genome analysis that multiple populations of piscivorous (fish-eating) herring have evolved sympatrically after the colonization of the brackish Baltic Sea within the last 8000 years postglaciation.
View Article and Find Full Text PDFNew Phytol
December 2024
Environmental Genomics, Christian-Albrechts University of Kiel, Am Botanischen Garten 1-11, 24118, Kiel, Germany.
The barley disease Septoria Speckled Leaf Blotch, caused by the fungus Zymoseptoria passerinii, last appeared in North America in the early 2000s. Although rare in crops, field sampling of wild grasses in the Middle East revealed the disease persistence in wild barley. Identification of Z.
View Article and Find Full Text PDFMol Ecol
December 2024
CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.
Speciation is a continuous process driven by barriers to gene flow. Based on genome-wide SNPs (single nucleotide polymorphisms) of 190 toads from 31 sampling sites of Scutiger boulengeri complex, we found evidence for monophyly which represented a continuous speciation process of at least six lineages in S. boulengeri, which radiated and exhibited varying degrees of divergence and gene flow.
View Article and Find Full Text PDFPlant Biol (Stuttg)
December 2024
Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Biosciences Center, Federal University of Pernambuco, Recife, Pernambuco, Brazil.
Interspecific hybridization plays an important role in plant evolution, contributing to taxonomic uncertainty through intermediate phenotypes or the emergence of novel traits. The characterization of hybridization is important to elucidate systematic relationships and its role in the diversification of lineages. The genus Cenostigma comprises neotropical legume trees with phylogenetic inconsistencies, and individuals showing intermediate morphology between sympatric species, suggesting natural hybridization.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!