Review of Malaysian black flies (Diptera: Simuliidae): note on new record on Simulium kalimantanense from Sabah

Black flies are the two-winged, small-bodied (3mm to 6mm) and blood-sucking insects of medical and veterinary importance. Female of certain species play a role as a vector of several disease agents including, Onchocerca volvulus, causative agent of human onchocerciasis. Despite their medical significance, the biodiversity of black flies in the Borneo part of Malaysia as well as other Southeast Asian countries (except Thailand, Vietnam and Indonesia) are unknown. Our recent visit to the Kangkawat Reserve within the Imbak Canyon Conservation Area (ICCA) has successfully discovered one new record from Malaysia, Simulium kalimantanense of the S. banauense species-group and one from Sabah, Simulium sarawakense of the S. epistum species-group. Based on these current findings, the total number of species and species-group of black flies inhabiting Malaysia has increased to 96 and 22 respectively

Comparative Assessment of Moyog River Watershed and Malaysia Water Quality Index

Water is vital to the existence of all living organisms, but this invaluable resource is badly threatened by fast-growing human population and urbanization when increasing number of rivers are polluted due to the uncontrolled human activities. Here, we report the assessment of Water quality of Moyog river through the Malaysia Water Quality Index (NWQI) versus Canadian Water Quality Index (CWQI) as well as Biological Monitoring Work Party (BMWP) index. Sampling stations were set at Kg. Kibunut (KB), Kg. Notoruss (NT) and Kg. Babagon (BB) located in middle stream, as well as Kg. Kibabaig (KG) located in the lower stream of the Moyog river. NWQI shows that all the selected sites except KG fall under First Class category indicating an excellent water quality of the river. However, under CWQI, water quality for both MY, NT and BB falls into Second Class and Third Class, respectively, signifying a deterioration of water quality, and inconsistency of NWQI and CWQI in the water quality assessment. Besides, through BMWP index approach, a total of 538 individuals belonging to 8 orders, 17 families and 18 genera identified during the whole sampling event. The BMWP index is in good agreement with CWQI and this implies that a more stringent and holistic NWQI should be proposed for better assessment of river water quality in Malaysia

Current and future effects of global change on a hotspot's freshwater diversity

Deforestation, climate change and invasive species constitute three global threats to biodiversity that act synergistically. However, drivers and rates of loss of freshwater biodiversity now and in the future are poorly understood. Here we focus on the potential impacts of global change on freshwater mussels (Order Unionida) in Sundaland (SE Asia), a vulnerable group facing global declines and recognized indicators of overall freshwater biodiversity. We used an ensemble of distribution models to identify habitats potentially suitable for freshwater mussels and their change under a range of climate, deforestation and invasion scenarios. Our data and models revealed that, at present, Sundaland features 47 and 32 Mha of habitat that can be considered environmentally suitable for native and invasive freshwater mussels, respectively. We anticipate that by 2050, the area suitable for palm oil cultivation may expand between 8 and 44 Mha, representing an annual increase of 2–11%. This is expected to result in a 20% decrease in suitable habitat for native mussels, a drop that reaches 30% by 2050 when considering concomitant climate change. In contrast, the habitat potentially suitable for invasive mussels may increase by 44–56% under 2050 future scenarios. Consequently, native mussels may compete for habitat, food resources and fish hosts with invasive mussels across approximately 60% of their suitable range. Our projections can be used to guide future expeditions to monitor the conservation status of freshwater biodiversity, and potentially reveal populations of endemic species on the brink of extinction. Future conservation measures—most importantly the designation of nature reserves—should take into account trends in freshwater biodiversity generally, and particularly species such as freshwater mussels, vital to safeguard fundamental ecosystem services.This study is funded by the Malaysian Ministry of Higher Education (Project FRGS/1/2015/WAB13/UNIM//1). BG was supported by a research fellowship funded by the Spanish Program of R + D + I (JCI2012-11908)

Fish Biodiversity and Water Quality of Tropical Forest Streams Adjacent to the Western Boundary of Kinabalu Park, Sabah

Modification and degradation of habitats outside the boundaries of a national park may result in the park's integrity being compromised. Thus, the present study aims to document variation in freshwater fish and water quality of tropical forest streams adjacent to the western boundary of Kinabalu Park, Sabah. Concurrently, fish samples and environmental parameters were collected at six stations covering a total streamline length of 10 km. The three most abundant species were Tor tambra (34.4%), Barbodes sealei (19.5%), and Lobocheilos ovalis (12.4%). Tor tambra exhibited a negative allometric growth pattern (coefficient < 3) and was in poor to fair condition (0.8 < Fulton’s condition factor < 1.2). The highest fish abundance was found in downstream stations with species addition. Metrics of diversity, such as Shannon's diversity index and the Margalef index of species richness, decreased as elevation increased from 100 to 600 metres above sea level. The water quality of the forest streams is good, classified as Class I and/or Class II by Malaysia's National Water Quality Standards, except for ammoniacal nitrogen at station 6, which was classified as Class III. Higher turbidity, orthophosphate, and ammoniacal-nitrogen values were found near the Podos village. In conclusion, the altitudinal gradient of fish biodiversity was observed in the forest streams near Kinabalu Park. Regular water quality monitoring of the downstream river is necessary, as indicated by the potential domestic impacts on the river

A new genus and two new, rare freshwater mussel (Bivalvia: Unionidae) species endemic to Borneo are threatened by ongoing habitat destruction

1. Most of the Bornean endemic freshwater mussel (Unionida) species known to date have not been recorded by science for the past 50 years or more, owing to a lack of research effort and presumed population losses.2. This study assessed current patterns and recent changes in the diversity and distribution of freshwater mussels in north-eastern Borneo. Physical surveys and interviews were conducted at 24 sites, and anecdotal evidence for current or historical presence of mussels was collected for a further 13 sites.3. Native species, i.e. Schepmania sp. and Khairuloconcha sahanae gen. & sp. nov., were only found in one small stream of the Kinabatangan River basin within the Gomantong Forest Reserve, whereas the non-native Sinanodonta cf. woodiana was common across the study area.4. Molecular phylogenetics (five genes) of the native taxa, including comparative material from West Kalimantan and Sarawak, revealed: (i) the presence of a new genus with two new, rare species: Khairuloconcha lunbawangorum sp. nov. in the Limbang River basin and K. sahanae in the Kinabatangan River basin; (ii) that Khairuloconcha and Ctenodesma form the Bornean endemic tribe Ctenodesmini trib. nov.; and (iii) that Schepmania represents another Bornean endemic tribe Schepmaniini trib. nov.5. Both Khairuloconcha gen. nov. species are known from a single stream each and are apparently restricted to forest stream habitats where they occur at very low densities. Schepmania appears to have a severely contracted range in the Kinabatangan and adjacent basins. We urgently call for full protection of the currently known sites of K. lunbawangorum and K. sahanae, and development of an action plan to save the Bornean freshwater mussel fauna

State and fate of Borneo’s freshwater mussel diversity

Abstract of World Congress of Malacology, July 31- August 5 2022, Munich, Germany.Peer reviewe

Changes and drivers of freshwater mussel diversity and distribution in northern Borneo

Human activities are threatening Borneo's unique biodiversity, but little is known on the status of freshwater invertebrates. We assessed changes in diversity and distribution of freshwater mussels (Bivalvia: Unionida) in northern Borneo, and identified drivers of present distribution and threats. Past distribution data were collected from literature and museum resources. Present distribution data were collected from 21 river basins, and 47 water quality, climatic, landscape and human variables explored as potential predictors of species presence/absence. Species delimitations were identified by morphology and COI barcoding, and haplotype networks generated. Our data indicate that over the past 50 years, four of originally five native species have become very rare or possibly locally extirpated. Since these four species are endemic to Borneo, other Bornean river basins should urgently be surveyed to identify any remaining populations. In the same time span, the non-native Sinanodonta woodiana has become the most widespread freshwater mussel in northern Borneo. The fifth native species was identified as Rectidens sumatrensis and found in four Sarawakian river basins, thus contradicting previous assumptions of an endemic Bornean Rectidens species. Although a number of stable R. sumatrensis populations are retained across Sarawak, the species' strong spatial contraction in mainland Sundaland and apparent low tolerance to eutrophication suggest that it is vulnerable to further habitat alteration. Our results indicate that Borneo's (endemic) freshwater invertebrate biodiversity is declining rapidly. Comprehensive surveys targeting an array of invertebrate and vertebrate taxa are needed to identify Borneo's freshwater biodiversity hotspots, where conservation efforts should be concentrated