Morphological and genetic confirmation of the millipede Chordeuma sylvestre C. L. Koch, 1847 new to Ireland

Gaul, W.; Tighe, A. J.

doi:10.1101/2020.05.17.100263

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bioRxiv · 10.1101/2020.05.17.100263

Morphological and genetic confirmation of the millipede Chordeuma sylvestre C. L. Koch, 1847 new to Ireland

Gaul, W.·Tighe, A. J.

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Abstract

We report the millipede Chordeuma sylvestre C. L. Koch, 1847 for the first time from Ireland. We used morphology of male gonopods and DNA barcoding of the COI gene from two individuals to confirm the identification of one male and one female collected from the campus of University College Dublin. DNA barcoding revealed two mitochondrial haplotypes, implying that colonization was from multiple females or eggs from multiple females. To evaluate how likely it is that C. sylvestre arrived relatively recently in Ireland, we used species richness estimates and species accumulation curves to evaluate the completeness of the species list compiled during two previous periods of intensive millipede recording going back to 1971. Millipede recording in Ireland was far from complete during the period 1971 – 1984, with multiple species present but undetected. Recording was more complete during the period 1986 – 2005. The area within 20 km of the new C. sylvestre records was poorly recorded during the period 1986 – 2005, so we cannot rule out the possibility that C. sylvestre has been in Dublin for at least a few decades. However, the disjunct location of the current records compared to the species’s known native range in northern France, the urban location of the current site, and the lack of records from the relatively intensive millipede recording in Ireland between 1986 and 2005 suggest that C. sylvestre is a recent anthropogenic introduction in Ireland.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Gaul, W., Tighe, A. J.. 2020-05-17. Morphological and genetic confirmation of the millipede Chordeuma sylvestre C. L. Koch, 1847 new to Ireland. https://doi.org/10.1101/2020.05.17.100263

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