Although Borneo has received more attention from biologists than most other islands in the Malay Archipelago, many questions regarding the systematic relationships of Bornean mammals remain. Using next-generation sequencing technology, we obtained mitochondrial DNA sequences from the holotype of Suncusater, the only known specimen of this shrew. Several shrews collected recently in Sarawak are closely aligned, both morphologically and mitochondrially, with the holotype of S.ater. Phylogenetic analyses of mitochondrial sequences indicate that the S.ater holotype and new Sarawak specimens do not belong to the genus Suncus, but instead are most closely related to Palawanosorexmuscorum. Until now Palawanosorex has been known only from the neighboring Philippine island of Palawan. Additional sequences from nuclear ultra-conserved elements from the new Sarawak specimens strongly support a sister relationship to P.muscorum. We therefore transfer ater to Palawanosorex. The new specimens demonstrate that P.ater is more widespread in northern Borneo than previously recorded. Continued sampling of Bornean mammal diversity and reexamination of type material are critical in understanding the evolutionary history of the biologically rich Malay Archipelago.
Bats are extraordinary mammals. They have evolved to consume various dietary sources, such as insects, fruits, nectar, blood, and meat. This diversity has generated considerable interest in the scientific community, resulting in efforts to leverage bats as model organisms to study the correlation between diet and gut microbiome community. Although such studies now commonly use Next Generation Sequencing (NGS), similar studies are early in their development in Southeast Asia, especially in Malaysia, which harbours an incredibly diverse bat fauna. This study provides pioneering NGS metabarcoding information on Bornean bats. By using a high-throughput Nanopore-based 16S rRNA gene sequencing method, Bacillota, Pseudomonadota, and Campylobacterota were found in insectivorous bats and phytophagous bats. Both insectivorous and phytophagous groups harboured no dominant taxon (D = 0.076; D = 0.085). A comparative analysis of gut bacteria functional groups identified eight major groups in both phytophagous and insectivorous bats, with fermentation being the predominant group. The correlation network analysis revealed a negative correlation between the 'good bacteria' Lactobacillus and various pathogenic bacteria genera, such as Salmonella (-0.4124) and Yersinia (-0.4654), demonstrating its prebiotic characteristics. This study broadens our understanding of the bat gut microbiome from various diets, with emphasis on new data from Borneo.