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Nicrophorus vespilloides is a burying beetle

Taxonomy
It was first formally described by the German entomologist and naturalist Johann Friedrich Wilhelm Herbst. In 1783 Herbst's description was published in his Kritisches Verzeichniss meiner Insectensammlung, part of the fourth heft of Zurich bookseller Johann Caspar Fuessly's Archiv der Insectengeschichte. The taxonomic history of Nicrophorus has been contentious, with workers disagreeing on the taxonomic signifiance of elytal colour variants. Some workers (e.g. Portevin in the nineteenth century)

Separation of N. hebes
In 2016 researchers published a review of the unity of the N. vespilloides taxon, motivated by the reported ecological differences between Nearctic and Palearctic populations. Most scientific work on N. vespilloides had been in the Palearctic, and here the beetle was found to be relatively common in forests and grassland; this contrasted strongly with the Nearctic where the beetle called N. vespilloides was rarely caught and restricted to bogs/marshes. DNA barcode data from the COI gene from 23 N.vespilloides individuals (14 from the Palearctic, five from Canada and four from Alaska) were downloaded from public databases and aligned. This genetic data was then used to construct an evolutionary tree using Bayesian methods: the tree strongly supported the existence of two distinct monophyletic groups within the N. vespilloides sampled, one group (clade) containing all and only the beetles from Canada and the other conaining all and only those from Alaska and the Palearctic. The two groups differed by an average of 3.74% genetically: this is significant as most animal species differ by at least 2% from their closest evolutionary relatives. . The Canadian clade contained zero within-group variation in contrast to the Palearctic-Alaskan clade in which sequences differed by 0.3% on average. Between-clade laboratory breedings produced fewer offspring than within-clade laboratory breedings, and offspring of between-clade pairings had a higher mortality rate than offspring of within-clade pairings, i.e. post-zygotic barriers exist between the two clades that make any interbreeding costly. There was no difference in the latency to mate between within-clade and between-clade pairings, consistent with a lack of pre-zygotic barriers.

Morphological analysis of over one thousand N.vespilloides museum specimens revealed two traits that differed between Canadian specimens and Alaskan-Palearctic specimens. The Canadian specimens usually have a short anterior black band on the side of their wingcase (their wikt:epipleuron) whilst in the Alaskan-Palearctic specimens' the epipleural band is usually longer. The Alaskan-Palearctic specimens also generally had bristles (setae) on their wikt:metepisternum (the wikt:episternum of their metathorax]) whilst the Canadian specimens usually have a bald metepisternum. The exception were specimens from the westerly Canadian Yukon and Northwest Territories (YT and NT respectively) grouped with the Alaskan-Palearctic clade morphologically: no genetic data was available for YT and NT populations, but based on their morphological characteristics they were amalgamated with the Alaskan-Palearctic clade. The combination of ecological, morphological and genetic disparites between the Alaskan + YT + NT + Palearctic clade and the Canadian clade, combined with the barrier to gene flow that the pre-zygotic isolating mechanism imposes, indicated that the two clades represented two distinct biological species (albeit cryptic ones). As the holotype of N. vespilloides was collected by Herbst in Berlin, the Alaskan + YT + NT + Palearctic kept the vespilloides specific epithet; the name Nicrophorus hebes Kirby (1837) was resurrected from synonymy and applied to the Canadian clade, its type locality being Nova Scotia.

Distribution
Alongside N. defodiens, N.vespilloides is one of only two of the 72 Nicrophorus species to have a Holarctic distribution, the others being confined to either the New or Old World. Most N. vespilloides records are north of the 40th parallel north, making it a relatively high-latitude species. Using DNA sequences from the