Scientia Bruneiana

Editorial and Introduction to the Special Issue

2026-07-04T20:03:09+00:00

This special issue of Scientia Bruneiana features 12 original papers, including one review article. The issue honours two founding members of FOS, whose work established the strong foundation on which the faculty has grown over the past three decades:
1) David Sydney Edwards (1948-2025), and 2) Jimmy Lim Chee Ming (1966–2026).

Updated Checklist of the Herpetofauna of Brunei Darussalam

2026-07-04T20:03:18+00:00

We provide an updated checklist of the herpetofauna of Brunei Darussalam based on literature data, citizen science records, field surveys, and opportunistic observations. Forty-four species are added to the checklist of the country, bringing the total number of herpetofauna in Brunei to 248 species (90 amphibians and 158 reptiles). The new records include the enigmatic Glyphoglossus flavus, G. smithi, Rhacophorus borneensis, Lanthanotus borneensis, four species of Calamaria, Gonyosoma margaritatum and a new species of rock gecko, Cnemaspis gituen. The additional species improve our knowledge on the herpetofaunal diversity of Brunei and their range distribution in this region. Our study also reflects the need for further field and taxonomic work as well as citizen-science involvement, to uncover the hidden herpetofaunal diversity of Brunei. With the expanding threat of extinctions, enhanced knowledge on Borneo’s biodiversity and their population trends will provide essential baseline information to support evidence-based conservation actions.

Identification of Seeds and Seedlings of Different Species of Plants Found in Universiti Brunei Darussalam

2026-07-04T20:03:01+00:00

Identification tools for fruits, seeds, or seedlings can greatly aid biodiversity rehabilitation projects. Since morphological and pictorial data are usually lacking, especially in species-rich tropical regions, this study aims to provide such data for Brunei. To accomplish this, fruits and seeds of different plant species were collected from forested areas inside Universiti Brunei Darussalam campus and described and photographed in a standardised way. The same was done for the seedlings that germinated from the collected seeds. A total of 21 species from 15 families were described although two species remained unidentified. Seedling descriptions are only provided for 17 species since not all the seeds were successfully germinated. For the two unknown species, fruit descriptions were not given since the fruits were not known. Furthermore, only the fruits from eight species were described based on direct observations while 11 were based on existing literature due to the unavailability of fruits on site. While the data from this study are useful for the public to identify fruits, seeds and seedlings, more studies are needed to document the many plant species of Brunei Darussalam not yet included in this study.

Decadal Change in the Kerangas Avifaunal Complex in Universiti Brunei Darussalam, Brunei Darussalam

2026-07-04T20:02:52+00:00

An urbanized forest habitat is often subjected to spatial and temporal changes in the avian assemblage that inhabits it. The Universiti Brunei Darussalam (UBD) campus built on a coastal kerangas forest (tropical heath) in 1985, is a case in point. This forest type is vulnerable to fires and extensive areas have been burnt over the years and parts of the chosen site for the campus too have been affected. Four avian surveys to study the extent of change in the species richness, were carried out in this site in 1989-1991, 1998-2000, 2006-2007 and 2019-2020. When comparing species richness between years and before and after the building of the campus, there was a significant decline after the campus was built. Three kinds of forests were surveyed - undisturbed contiguous forests, fragmented kerangas sites and the UBD kerangas. To understand the significance of this change, the species richness in undisturbed contiguous sites was five times greater than in the fragmented sites, while that in UBD was twice greater than in the fragmented sites. Furthermore, contiguous sites showed a high dissimilarity from the fragmented disturbed sites. Though UBD was grouped together with the fragmented sites it showed a high dissimilarity from them. As expected, species richness increases with site area, the large contiguous kerangas sites harbouring more species than the small fragmented disturbed sites. A scrutiny of the avian species assemblage shows a large shift from the presence of kerangas forest species before building of the campus to habitat generalists especially granivores at present, characteristic of an urbanized forest habitat.

Natural and Artificial Rocky Shores of Brunei, Including a Preliminary Checklist of Invertebrate Species

2026-07-04T20:02:42+00:00

This review summarises current knowledge of Brunei Darussalam’s rocky shore ecosystems. Although wave-washed rocky shores comprise a small fraction of the local coastal habitats, which are dominated by sandy beaches, mangroves, and mudflats, they support distinct and diverse faunal communities. We describe the formation, physical environment and biotic zonation of both natural and artificial rocky shores and compare the factors driving habitat heterogeneity for each shore. We also outline the known species diversity and the human impact on these shores. Two hundred and ten (210) invertebrate species are reported to occur on these shores, with intertidal gastropods (61 species) and subtidal cnidarians (45 species) being the best represented. Other typically diverse taxa, including sponges, crustaceans (decapods and amphipods) and polychaetes, however, remain poorly documented. The natural shores are continuously being disturbed and degraded by human activity, threatening local species extinction and reducing resilience and population recovery potential. This pressure is somewhat offset by the recent establishment of artificial rocky shores, which enhance the subtidal habitat and present novel intertidal habitat with respect to wave action exposure, especially the sheltering of rocky shores in modified embayment systems. Ecologically, artificial structures should facilitate greater colonization and recolonization potential by enhancing habitat and local larval supply. However, these structures present a small subset of the habitat types found on natural shores. Importantly, the artificial shores lack low-sloped or horizontal surfaces that trap waterbodies (tidal pools) during emersion and microhabitat/substratum complexity, both of which drive habitat heterogeneity and species diversity. We therefore call for further coastal research as a priority, to support effective conservation management of the remaining natural shores and to improve understanding of the ecological functions of artificial shores. Because of their limited extent, these ecosystems have been overlooked in the past, and this undermines Brunei’s responsibility for biodiversity conservation and its commitments within its national jurisdiction under international treaties.

Influence of Sound Pressure Level of Frog Advertisement Calls on Attraction of Frog-Biting Midges

2026-07-04T20:02:33+00:00

Frog-biting midges (Diptera: Corethrellidae) have evolved the ability to eavesdrop on the distinctive acoustic signals emitted by male frogs from which they obtain a blood meal. Acoustic traps broadcasting the advertisement calls of Collett’s treefrog, Polypedates colletti, at 80 dB versus 90 dB sound pressure level were used to test the influence of sound pressure level on midge attraction. An increase in call amplitude by 10 dB led to a 5-fold increased capture rate, suggesting that amplitude is a critical factor in determining frog-biting midge attraction and the incidence of parasitism.

Four New Records of Astropecten Seastar (Asteroidea: Astropectinidae) from Brunei

2026-07-04T20:02:25+00:00

Establishing definitive regional species records is crucial to understand how marine faunas change under anthropogenic stresses. Other than reef corals, the marine invertebrate species diversity of Brunei Darussalam and in fact the entire Palawan-North Borneo ecoregion is relatively poorly known. The present study reports the first records of the occurrence of four species of the seastar genus, Astropecten, from muddy/sandy, intertidal and benthic ecosystems in Brunei. We briefly describe the species, showing key distinguishing features, and discuss their distributions in modified coastal ecosystems and natural embayments in Brunei. Finally we discuss the geographical distributions of these species within the South China Sea and elsewhere.

Benthic Faunal Ecology in the Algal Turf Zone of a Bornean Rocky Shore: the Influence of Habitat-Forming Species

2026-07-04T20:02:16+00:00

Brunei lies within the highly diverse Palawan-North Borneo ecoregion, but taxonomic and ecological assessments of the benthic marine fauna are distinctly lacking. Local intertidal ecosystems are dominated by sandy beaches, mudflats and mangroves, with sparsely distributed rocky shores. We studied the fauna and community ecology associated with the low-shore algal turf zone of the only remaining ‘undisturbed’ natural rocky shore of Brunei (the Empire). We assessed the macrobenthic invertebrate species and tested whether assemblage structure related to turf habitat complexity (16 samples; 20×20 cm). Comparisons were made between two categories of substratum, (1) finely branched and (2) broadly expanded substrata, determined by the predominance of differently structured coralline and green algae, and sessile animals (sponge and mussels). More than 1099 macrofaunal specimens were retrieved from the samples, comprising 30 families and 46 OTUs (Operational Taxonomic Unit), with the most abundant groups being amphipods (12 OTUs), ostracods (2), tanaidaceans (2), isopods (3), polychaetes (5) and gastropods (22). Multivariate analyses based on 25 common OTUs revealed significant dissimilarity in assemblages associated with the different substrate types. Indicator species analysis identified amphipods (abundant in coralline algae) and tanaidaceans (abundant on flat substrates) as contributing the most to this differentiation (28.63% for three species). The gastropod, Zafra cf. troglodytes (17.7%) and the ostracod cylindroleberid sp. (14.3%) contributed the most to assemblage similarity of the finely branched and expanded substrates, respectively. The drivers of habitat preference, and local spatial and temporal variation in assemblage structure are discussed. This work adds to our knowledge of local rocky shore benthic ecology but reveals a dire need for dedicated taxonomic work to resolve the species, crucial for appropriate environmental conservation and management.

Stem Abundance, Basal Area and Species Richness of Intact and Degraded Kerapah Forest Plots in Lumut, Brunei Darussalam

2026-07-04T20:02:08+00:00

Kerapah forests are a rare form of permanently waterlogged tropical heath forest that develop on highly acidic, nutrient-poor soils and support a distinctive flora adapted to harsh edaphic conditions. In Brunei Darussalam, these forests are increasingly threatened by deforestation and degradation, yet quantitative information on their forest structure and species composition remains limited. This study presents baseline structural and floristic data by comparing stem abundance, basal area, and species richness between intact Kerapah forest stands and areas that were completely cleared in 2012 and allowed to regenerate naturally for five years prior to sampling in Lumut, Brunei Darussalam. Six plots (three intact and three cleared), each measuring 15 × 50 m, were established, and all trees with diameter at breast height (DBH) ≥ 6 cm were measured and identified to species level. Forest structural attributes, diameter class distribution, and species composition were analysed and compared between forest conditions. Intact forest plots exhibited substantially higher stem abundance, basal area, and species richness per plot than cleared forest plots (101.3 ± 14.3 vs. 2 stems, 41.9 ± 7.7 vs. 0.08 m² ha⁻¹, and 27.7 ± 1.9 vs. 2 species, respectively). Diameter class distribution in intact forests was characterised by a high proportion of pole-sized and young adult trees, indicating ongoing regeneration, whereas cleared plots contained only pole-sized individuals, reflecting severe structural simplification and limited recovery. The intact plots supported multiple tree species listed on the IUCN Red List, including Critically Endangered (Gonystylus bancanus), Endangered (Dryobalanops rappa, Rubroshorea pachyphylla), and Vulnerable species (Lithocarpus andersonii, Madhuca curtisii, Rubroshorea albida), underscoring the high conservation importance of intact Kerapah forests. In contrast, cleared plots lacked threatened species and characteristic dominants, possibly because 5 years was too short to observe any meaningful regeneration. This study provides an important ecological baseline to inform evidence-based rehabilitation, conservation planning, and long-term management of Kerapah forests in Brunei Darussalam.

Foliar Trait and Nutrient Differences Between Invasive Acacia and Native Species in Disturbed Coastal Kerangas Forests of Brunei Darussalam

2026-07-04T20:01:59+00:00

Invasive Acacia species are fast-growing exotic trees that were introduced to Brunei Darussalam in the 1990s for plantation forestry and land rehabilitation. Over time, several Acacia species have spread beyond planted areas and are now invading disturbed coastal Kerangas (tropical heath) forests, raising concerns about their impacts on native vegetation adapted to nutrient-poor conditions. However, information on the functional traits associated with Acacia invasion in Brunei’s Kerangas ecosystems remains limited. This study investigated differences in selected foliar traits and foliar nutrient concentrations among three invasive Acacia species (Acacia auriculiformis, Acacia holosericea and Acacia mangium) and six co-occurring native species (Buchanania arborescens, Calophyllum soulattri, Dillenia suffruticosa, Melastoma malabathricum, Ploiarium elegans and Symplocos polyandra,), which represent a range of functional strategies present in disturbed Kerangas habitats. Measured foliar traits included leaf thickness, specific leaf area (SLA), leaf dry matter content (LDMC) and green leaf tissue pH, while foliar nutrients assessed were leaf nitrogen content (LNC) and leaf phosphorus content (LPC). Results showed that invasive Acacia species, particularly Acacia auriculiformis and Acacia mangium, exhibited significantly higher SLA, thinner leaves and higher foliar nutrient concentrations compared to native Kerangas species. These traits indicate a resource-acquisitive strategy associated with rapid growth and competitive ability under disturbed conditions. In contrast, native Kerangas species displayed lower SLA, higher LDMC and greater investment in leaf structural traits, reflecting conservative resource-use strategies consistent with adaptation to nutrient-poor environments. Dillenia suffruticosa exhibited trait characteristics similar to invasive Acacia species, while Melastoma malabathricum showed mixed strategies. Other native species were associated with more conservative trait syndromes. Overall, the findings indicate that differences in foliar traits and nutrient allocation strategies are likely to contribute to the invasion success of Acacia species in coastal Kerangas forests, with potential implications for the persistence of Brunei’s increasingly rare Kerangas ecosystems.

Tropical Fern Flora of Brunei Shows Entire Fronds in Epiphytic Species and Divided Fronds in Terrestrial Species: Two Working Hypotheses to Explain Such Morphological Differences

2026-07-04T20:01:50+00:00

Fern species are famous for their frond division, often used as a fractal representation. Fronds can be entire, or divided into first, second and third orders of division. In general, fern species tend to have divided fronds, while species with entire fronds are less common. In tropical regions, where fern species reach their highest richness and morphological diversity, the frequency of entire fronds versus divided fronds has rarely been studied. In this study, I present the frond division pattern for the fern flora of Brunei Darussalam. I use the recently published checklist of the ferns of Brunei Darussalam, which lists 341 species. I also divided the species by their life form: terrestrial and epiphytic. Terrestrial species represent 60% of the Brunei fern diversity, while epiphytes represent the remaining 40%. I find that terrestrial species have the highest proportion of first-order frond division, followed by entire fronds, second-order fronds, and third-order fronds. In contrast, the epiphyte species are predominantly represented by entire fronds, followed by first-order frond division. I conclude this article with two working hypotheses to explain this remarkable morphological difference between the two tropical life forms.

A Comparative Evaluation of the Wound Healing Properties of Stingless Bee Honey in Diabetic Animal Models

2026-07-04T20:01:42+00:00

Diabetes is commonly associated with delayed wound healing, highlighting the need for alternative wound management approaches. This study evaluates the wound-healing potential of honey from two stingless bees from Brunei Darussalam, Geniotrigona thoracica and Heterotrigona itama, in alloxan-induced diabetic Wistar rats. The honey was applied topically at 100% concentration to excision wounds for a period of 14 days, with normal non-diabetic and diabetic untreated rats used as controls. Wound contraction was assessed using ImageJ while histological analysis was performed on Day-6 post wounding to evaluate tissue repair. Wound contraction increased in all groups with G. thoracica treated group showing significantly higher wound contraction on Day 7 and Day 10 at 72.9 ± 6.7% and 92.3 ± 2.09 % respectively. Histological analysis on Day 6 showed reduced inflammatory cell infiltration, increased collagen deposition, and improved re-epithelialisation in the honey-treated groups. These findings suggest that Brunei stingless bee honey, particularly G. thoracica, may promote wound healing in diabetic rats and has potential as a natural wound management agent.

A Case Report: Rapid Progression of Postpartum Uterine Rupture to Sepsis and Multi Organ Dysfunction (MOD) in a Boer Goat (Capra aegagrus hircus)

2026-07-04T20:01:32+00:00

A two-year-old female Boer goat in Belait district, Brunei Darussalam died within 24 hours postpartum following abnormal vulvar discharge. Investigation into the cause of the death was conducted by post-mortem examination and targeted histological assessment of affected organs. Post-mortem revealed a ruptured and disintegrated uterus with dark, mucoid fluid, unilateral mastitis, pulmonary congestion, hepatic pallor, renal cortical discoloration, and myocardial striations. Histopathology demonstrated lymphocytic infiltration in the uterus, kidneys, and myocardium, alveolar oedematous hemorrhage, and fat accumulation in the epicardial space. The findings are consistent with peritonitis and sepsis leading to multi-organ dysfunction (MOD). The rapid progression from parturition to death highlights the peracute nature of postpartum uterine rupture and its systemic consequences in goats. Regular monitoring and preventive care during the postpartum period are essential to reduce the risk of complication and ensure the health of the animal.