Life Cycle and Development ofCoptoborus ochromactonus(Coleoptera: Curculionidae: Scolytinae), a pest of balsa

The Essential Role of Taxonomic Expertise in the Creation of DNA Databases for the Identification and Delimitation of Southeast Asian Ambrosia Beetle Species (Curculionidae: Scolytinae: Xyleborini)

“…The uncommon haplodiploid mating system of Xyleborini may provide the best explanation for the high intraspecific COI sequence differences. The diploid female/haploid male sex-ratio is skewed on average 13:1 and ranges from 2:1 to 83:1 (French and Roeper, 1975;Beaver and Browne, 1979;Kirkendall, 1993;Cooperband et al, 2016;Castro et al, 2019). A female has an apparent greater chance of reproducing compared to diploid-diploid species because if unmated she lays a haploid egg which produces a male.…”

“…Xyleborine ambrosia beetles (Curculionidae: Scolytinae) occur throughout the world's forests with most of the diversity in the moist tropics where they comprise the majority of the scolytine diversity (Browne, 1961;Wood and Bright, 1992;Hulcr et al, 2015). These beetles exhibit two conspicuous life history traits: they cultivate symbiotic fungi for food in tunnels that they bore into recently dead trees (and their parts), and they are haplodiploid and highly inbred with female-skewed sex ratios averaging 13:1 (Kirkendall, 1993;Cooperband et al, 2016;Castro et al, 2019). These traits have allowed these beetles to colonize the world and gave them their infamous reputation as potential invasive species (Jordal et al, 2001;Gohli et al, 2016;Brockerhoff and Liebhold, 2017).…”

A revision of the Neotropical genus Coptoborus Hopkins (Coleoptera, Curculionidae, Scolytinae, Xyleborini)

“…This species has only been collected from balsa, Ochroma pyrimidale ( Malvaceae ), and is a serious pest of balsa in Ecuador. The biology of C. ochromactonus has been studied in detail ( Stilwell et al 2014 ; Castro et al 2019 ; Martínez et al 2020 ).…”

“…Of these ambrosia beetle genera, Coptoborus Hopkins, 1915 and Theoborus Hopkins, 1915 are similar in morphology, closely related and comprise ~30 species ( Wood 2007 ; Cognato et al 2011 ). Theoborus coartatus (Sampson, 1921), T. theobromae Hopkins, 1915, T. villosulus (Blandford, 1898), Coptoborus tolimanus (Eggers, 1928), and C. vespatorius (Schedl, 1931) have long been recognized as pests of cacao ( Terra 1987 ) and a newly emerging pest, Coptoborus ochromactonus Smith & Cognato, 2014 ( Stilwel et al 2014 ) threatens balsa wood production ( Stilwel et al 2014 ; Castro et al 2019 ; Martínez et al 2020 ), but otherwise, the remaining species are assumed benign. An accumulation of recently collected specimens and museum loans which represents hand collected material from dispersed Neotropical localities and specimens from the Ecuadorian Amazonian canopy, presents an opportunity to re-examine the generic limits of Coptoborus and Theoborus and to contribute to the knowledge of the alpha diversity of xyleborines.…”

Novel Symbiotic Association Between Euwallacea Ambrosia Beetle and Fusarium Fungus on Fig Trees in Japan

“…In this study, the sex ratio of adults emerging from the galleries was about 31:1 (♀: ♂). This value was much higher than that of Xyleborini ambrosia beetle which has an average ratio of 13:1 (Kirkendall, 1993;Cooperband et al, 2016;Castro et al, 2019;Cognato et al, 2020). A total of 51 adult specimens (female and alive) were randomly selected and used for fungal isolation during March 2, 2018-April 6, 2018 (Supplementary Table 1).…”