First records of penicillate millipedes (Diplopoda, Polyxenidae) from Thailand, with descriptions of two new species

Two new species are described from the family Polyxenidae. Monographis panhai sp. nov. and Unixenus thailandicus sp. nov. represent the first records of their respective genera in Thailand. Monographis panhai sp. nov. shows distinct morphological differences in the arrangement of sensilla in the antennomere VI, as well as in the structures of the labrum and the claw. Collections from different areas of Thailand showed that not only is it widespread but also exhibits geographic variation in morphology. Unixenus thailandicus sp. nov. exhibits sexual dimorphism in the number of conical sensilla on the lateral palp, with 24 in males and 22 in females, differing from the typical count of 13 within the genus.

Revealing the millipede and other soil-macrofaunal biodiversity in Hong Kong using a citizen science approach

Background

Soil biodiversity plays important roles in nutrient recycling in both the environment and agriculture. However, they are generally understudied worldwide. To reveal the diversity of soil macrofauna in Hong Kong, here we initiated a citizen science project involving university, non-governmental organisations and secondary school students and teachers. It is envisioned that the citizen science approach used in this study could be used as a demonstration to future biodiversity sampling and monitoring studies.

New information

Throughout a year of monitoring and species sampling across different localities in Hong Kong, 150 soil macrofaunal morphospecies were collected. Eighty five of them were further identified by morphology and DNA barcoding was assigned to each identified morphospecies, yielding a total of 646 DNA barcodes, with new millipede sequences deposited to the GenBank. The soil macrofauna morphospecies in Hong Kong found in this study are mainly dominated by millipedes (23 out of 150) and oligochaetes (15 out of 150). Amongst the twenty three identified millipedes, two polyxenid millipedes, Monographisqueenslandica Huynh & Veenstra, 2013 and Alloproctoidesremyi Marquet and Condé, 1950 are first recorded in Hong Kong. Information has been curated on an online platform and database (http://biodiversity.sls.cuhk.edu.hk/millipedes). A postcard summarising the findings of millipedes in Hong Kong has also been made as a souvenir and distributed to citizen participants. The identified macrofauna morphospecies and their 646 DNA barcodes in this study established a solid foundation for further research in soil biodiversity.