Non-native; accidental introduction
Siphonethus dudleycookeorum is a distinctive species with a brown body and a small triangular head, similar in appearance to the native Polyzonium germanicum, but differs in a number of morphological characters and particularly in habitat and distribution.
Following morphological and genetic analysis this was recognised as a species new to science. A full description is given by Moritz, Gregory & Wesener, 2022.
A male and several females were collected from an ornamental garden in Cornwall in September 2020. Additional specimens were seen in November 2021.
Other known species in this genus are endemic to New Zealand and this species thought to have been introduced into Cornwall from there.
Specimens have been found within soil and leaf-litter and beneath 'logs' lying on the ground (cut tree fern stems) in an area dominated by introduced tree ferns.
Leif Moritz, Steve J. Gregory & Thomas Wesener (2022) A pinhead millipede astray: a new polyzoniidan millipede from New Zealand in Great Britain and the genus Siphonethus Chamberlin, 1920 in New Zealand (Polyzoniida: Siphonotidae). New Zealand Entomologist 44(2): 88-120. DOI: 10.1080/00779962.2022.2071001
MilliBase - Global catalogue of Millipedes: https://millibase.org/aphia.php?p=taxdetails&id=1591522
