The species of the ant genusStrumigenysSmith, 1860 found in Hong Kong are reviewed based on new sampling efforts performed over the past five years (2014–2018). Prior to this, 12Strumigenysspecies had been recorded from Hong Kong, all confirmed here. Moreover, we add to this list three newly described species:S.hirsutasp. n.,S.lantauisp. n., andS.nathistorisocsp. n., and describe for the first time the worker caste ofS.formosaTerayama, Lin & Wu, 1995. We report new records for nine additional species, bringing the total number of species to 24, including four newly recorded species (S.hexameraBrown, 1958,S.membraniferaEmery, 1869,S.nepalensisBaroni Urbani and De Andrade, 1994, andS.rogeriEmery, 1890) which are considered to be introduced to Hong Kong. A global review of the introducedStrumigenysspecies is presented. The taxonomic validity ofS.feaeandS.formosensisis discussed in light of new specimen measurements. New ecological information on the swarming periods of 11 species is presented on the basis of year-long sampling of aerial insects. Finally, the importance of our results within Southeast Asia and the need for future sampling efforts in the region is discussed.

We report surveillance conducted in 217 pestiferous rodents in Hong Kong for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We did not detect SARS-CoV-2 RNA but identified 1 seropositive rodent, suggesting exposure to a virus antigenically similar to SARS-CoV-2. Potential exposure of urban rodents to SARS-CoV-2 cannot be ruled out.

Some species of cynipid wasp engage in mutualisms with ants by producing nectar‐secreting galls, providing carbohydrates, and receiving protection from parasitoids. The galls are functionally similar to extrafloral nectaries, plant structures well known for their role in ant–plant mutualisms. Though not well known, nectar‐secreting galls may have important ecological and evolutionary implications for arthropods, plants, and the evolution of ant‐mutualisms. Here, I review the known ecology of nectar‐secreting galls and speculate on their wider ecological significance based on past research and similar ecological systems. I then develop a conceptual framework for considering the possible historical role of nectar‐secreting galls in the evolution of ant‐mutualisms. I review current knowledge on the origin of ant‐mutualisms and develop a hypothesis for the role of nectar‐secreting galls using examples of similar, contemporary species interactions. Finally, I lay out some of the future directions for research into nectar‐secreting galls and their species interactions, including important questions that remain to be addressed. Future studies of the diversity and ecology of nectar‐secreting galls are necessary to determine the extent to which they may be involved in ecological functioning and the evolution of ant‐mutualisms, and it is hoped that this review will contribute to motivating and developing future research.

Metabarcoding is rapidly gaining popularity as a means of conducting biodiversity studies. Using DNA barcodes to identify and catalog biodiversity has many advantages, and compares favorably with traditional methods based on morphological examination. Ease of use, taxonomic coverage, and increased efficiency are qualities that make metabarcoding a valuable ecological tool, particularly in light of the drastic anthropogenically induced ecosystem changes currently underway. However, limitations and challenges pertaining to existing barcodes create gaps from which inaccuracies can arise, contributing to skepticism regarding the value of metabarcoding based methods. Developing novel ways to address these limitations is crucial to improve metabarcoding methods and dispel doubt about their utility. Ultraconserved genomic elements (UCEs), genetic markers that have been used successfully in the field of phylogenomics, possess advantageous qualities that may be applied to fill in the gaps of existing metabarcoding methods. Here, I outline the strengths of UCEs and discuss their potential for complementing and strengthening existing metabarcoding methods based on the mitochondrial marker cytochrome oxidase I (COI).