The responses of lowland tropical communities to climate change will critically influence global biodiversity but remain poorly understood. If species in these systems are unable to tolerate warming, the communities-currently the most diverse on Earth-may become depauperate ('biotic attrition'). In response to temperature changes, animals can adjust their distribution in space or their activity in time, but these two components of the niche are seldom considered together. We assessed the spatio-temporal niches of rainforest mammal species in Borneo across gradients in elevation and temperature. Most species are not predicted to experience changes in spatio-temporal niche availability, even under pessimistic warming scenarios. Responses to temperature are not predictable by phylogeny but do appear to be trait-based, being much more variable in smaller-bodied taxa. General circulation models and weather station data suggest unprecedentedly high midday temperatures later in the century; predicted responses to this warming among small-bodied species range from 9% losses to 6% gains in spatio-temporal niche availability, while larger species have close to 0% predicted change. Body mass may therefore be a key ecological trait influencing the identity of climate change winners and losers. Mammal species composition will probably change in some areas as temperatures rise, but full-scale biotic attrition this century appears unlikely.
The rising sea level at the end of the Pleistocene that created the islands of the Sunda Shelf in Indonesia and Malaysia provides a natural experiment in community disassembly and offers insights into the effects of body size and niches on abundance, distribution, and diversity. Since isolation, terrestrial mammal communities of these islands have been reduced by extinction, with virtually no offsetting colonization. We document three empirical patterns of disassembly, all of which are significantly different from null models of random assembly: (i) a diversity-area relationship: the number of taxa is strongly and positively correlated with island area; (ii) nested subset composition: species that occur on small islands tend to be subsets of more diverse communities inhabiting larger islands; and (iii) body size distributions: species of intermediate body sizes occur on the greatest number of islands, and smaller islands have smaller ranges of body sizes, caused by the absence of species of both very large and extremely small size. These patterns reveal the role of body size and other niche characteristics, such as habitat requirements and trophic status, in the differential susceptibility of taxa to extinction.
Two new species of Paraneseuthia are described from peninsular Malaysia: P. joeparkeri sp. n. from Bukit Larut (Maxwell Hill) and P. titiwangsana sp. n. from the Genting Highlands. The new species are morphologically allied to species known so far only from Sumatra; they all share emarginate apex of the aedeagus bordered at each side by a subtriangular projection and a pair of setae. This is the first record of this eutheiine genus from the Malay Peninsula and extends the known diversity of Paraneseuthia species within the historical Sundaland area.
M. megabinluyog spec. nov. is described from a location in Brunei on the island of Borneo. Additional illustrations of its sister species M. astamii are provided.
Meristic, morphometric and distributional patterns of cyprinid fishes of the genus Neolissochilus found in Peninsular Malaysia are presented. Based on the current concept of Neolissochilus, only two species are present: N. soroides and N. hendersoni. Neolissochilus hendersoni differs from N. soroides by having lower scale and gill raker counts. Neolissochilus soroides has three mouth types (normal with a rounded snout, snout with a truncate edge, and lobe with a comparatively thick lower lip). A PCA of log-transformed measurements did not reveal significant differences between N. hendersoni and N. soroides, or between any of the morphotypes of N. soroides; however, a CVA of log-transformed measurements successfully classified 87.1% of all specimens. Removing body size by running a CVA on all of the principal components except PC1 (which was correlated with length) only slightly decreased the successful classification rate to 86.1%. Differences in morphometrics were as great between the three morphotypes of N. soroides as between any of the morphotypes and N. hendersoni suggesting that the morphotypes should be examined in greater detail with genetic tools. The PCA of morphometrics revealed separate clouds for N. hendersoni and N. soroides, but no differences between the N. soroides morphotypes. This study revealed that N. hendersoni is recorded for the first time in the mainland area of Peninsular Malaysia. Other nominal species of Neolissochilus reported to occur in the river systems of Peninsular Malaysia are discussed. Lissochilus tweediei Herre in Herre & Myers 1937 and Tor soro Bishop 1973 are synonyms of Neolissochilus soroides.
An illustrated key is provided to the economically important Thripinae (Thysanoptera) of Malaysia, together with a checklist and information on hosts and distributions. Information about the diversity and pest status for these Thripinae is provided, together with the prominent character states that are useful for recognising each species.
The monotypic genus Paracyriothasastes Breuning, 1978 was established for Cereopsius marmoreus Pascoe, 1857 from Malaysia. Uraechoides Breuning, 1981 was established for Uraechoides vivesi Breuning, 1981 also from Malaysia, and is currently composed of the type species and U. taomeiae Hayashi, Nara Yu, 1995, the latter from China (Taiwan) (Tavakilian Chevillotte 2020).
The genus Theopea Baly, 1864 is redefined. Seventeen species from Sundaland and the Philippines are recognized and classified into four species groups (including seven new species): T. impressa (Fabricius, 1801), T. longicollis (Jacoby, 1896), T. louwerensi Jolivet, 1951, T. lunduensis Mohamedsaid, 1998, T. chungi sp. nov. in the T. impressa group; T. flavipalpis Laboissère, 1940, T. guoi sp. nov., T. lui sp. nov., T. sabahensis sp. nov. in the T. flavipalpis group; T. elegantula Baly, 1864, T. pulchella Baly, 1864, T. fairmairei Duvivier, 1885, T. kedenburgi Weise, 1922, T. houjayi sp. nov., T. tsoui sp. nov., T. yuae sp. nov. in the T. pulchella group; and T. costata (Allard, 1889) in the T. costata group. The following new synonyms are established: Theopea pulchella Baly, 1864 = T. nigricollis Jacoby, 1892 syn. nov.; Theopea impressa (Fabricius, 1801) = T. impressa flavicornis Laboissère, 1940 syn. nov. and T. impressa malaccana Laboissère, 1940 syn. nov.; T. lunduensis Mohamedsaid, 1998 = T. sepilokensis Mohamedsaid, 2000 syn. nov. Lectotypes are designated for Crioceris impressa Fabricius, 1801, Ozomena longicollis Jacoby, 1896, Theopea elegantula Baly, 1864, T. fairmairei Duvivier, 1885, T. nigricollis Jacoby, 1892, and T. pulchella Baly, 1864. Theopea obliterata Jacoby, 1884, T. variabilis (Jacoby, 1887), T. incostata (Allard, 1889), T. clypeata Jacoby, 1896, T. modiglianii Jacoby, 1896, T. dohrni (Jacoby, 1899), T. viridipennis (Jacoby, 1899), and T. weberi (Weise, 1913) are removed from Theopea and regarded as species incertae sedis.
Earthworm specimens collected from various parts of Thailand were found to contain seven new species of the genus Metaphire Sims & Easton, 1972. These are M. songkhlaensis sp. n. in the octothecal pulauensis species group, M. trangensis sp. n. in the octothecal ignobilis species group, M. khaoluangensis sp. n. and M. khaochamao sp. n. in the sexthecal houlleti species group, M. doiphamon sp. n. in the sexthecal peguana species group, M. saxicalcis sp. n. in the quadrithecal planata species group, and the bithecal M. surinensis sp. n. Type material of some established species from Thailand or northern Malaysia was reinvestigated and illustrated to confirm the status of the new species and to facilitate species comparisons: M. pulauensis (Beddard, 1900), M. baruana (Stephenson, 1932), both with newly designated lectotypes, and M. planata (Gates, 1936), illustrated and redescribed.
Most of arthropod biodiversity is unknown to science. Consequently, it has been unclear whether insect communities around the world are dominated by the same or different taxa. This question can be answered through standardized sampling of biodiversity followed by estimation of species diversity and community composition with DNA barcodes. Here this approach is applied to flying insects sampled by 39 Malaise traps placed in five biogeographic regions, eight countries and numerous habitats (>225,000 specimens belonging to >25,000 species in 458 families). We find that 20 insect families (10 belonging to Diptera) account for >50% of local species diversity regardless of clade age, continent, climatic region and habitat type. Consistent differences in family-level dominance explain two-thirds of variation in community composition despite massive levels of species turnover, with most species (>97%) in the top 20 families encountered at a single site only. Alarmingly, the same families that dominate insect diversity are 'dark taxa' in that they suffer from extreme taxonomic neglect, with little signs of increasing activities in recent years. Taxonomic neglect tends to increase with diversity and decrease with body size. Identifying and tackling the diversity of 'dark taxa' with scalable techniques emerge as urgent priorities in biodiversity science.
The taxonomy of poorly known crickets from the genus Pendleburyella Chopard, 1969 (Gryllidae, Pentacentrinae) is reviewed. The type specimens of described species were re-located and re-examined. Based on more recent collections, we describe two new species: Pendleburyella eirmosa sp. nov. and Pendleburyella pimela sp. nov., from Brunei Darussalam and Singapore respectively. The new material also allowed us to examine the male genitalia and describe the male calling song of the genus for the first time.
Both community composition changes due to species redistribution and within-species size shifts may alter body-size structures under climate warming. Here we assess the relative contribution of these processes in community-level body-size changes in tropical moth assemblages that moved uphill during a period of warming. Based on resurvey data for seven assemblages of geometrid moths (>8000 individuals) on Mt. Kinabalu, Borneo, in 1965 and 2007, we show significant wing-length reduction (mean shrinkage of 1.3% per species). Range shifts explain most size restructuring, due to uphill shifts of relatively small species, especially at high elevations. Overall, mean forewing length shrank by ca. 5%, much of which is accounted for by species range boundary shifts (3.9%), followed by within-boundary distribution changes (0.5%), and within-species size shrinkage (0.6%). We conclude that the effects of range shifting predominate, but considering species physiological responses is also important for understanding community size reorganization under climate warming.
*Three Bornean pitcher plant species, Nepenthes lowii, N. rajah and N. macrophylla, produce modified pitchers that 'capture' tree shrew faeces for nutritional benefit. Tree shrews (Tupaia montana) feed on exudates produced by glands on the inner surfaces of the pitcher lids and defecate into the pitchers. *Here, we tested the hypothesis that pitcher geometry in these species is related to tree shrew body size by comparing the pitcher characteristics with those of five other 'typical' (arthropod-trapping) Nepenthes species. *We found that only pitchers with large orifices and lids that are concave, elongated and oriented approximately at right angles to the orifice capture faeces. The distance from the tree shrews' food source (that is, the lid nectar glands) to the front of the pitcher orifice precisely matches the head plus body length of T. montana in the faeces-trapping species, and is a function of orifice size and the angle of lid reflexion. *Substantial changes to nutrient acquisition strategies in carnivorous plants may occur through simple modifications to trap geometry. This extraordinary plant-animal interaction adds to a growing body of evidence that Nepenthes represents a candidate model for adaptive radiation with regard to nitrogen sequestration strategies.
The genus Pedionis with its species Pedionis (Pedionis) rufoscutellata Huang & Viraktamath, 1993 is recorded for the first time from Malaysia. A new species Pedionis (Pedionis) spiculata sp. nov. is described and illustrated. An updated species checklist with distribution of the genus Pedionis is also provided.
Three new species, B. catopuma sp. nov. (♀) (Borneo, Malaysia), B. musang sp. nov. (♂♀) and B. tangalunga sp. nov. (♂) (both from Mindanao, Philippines), are described. Species of shakeit group are recorded outside of Borneo for the first time (Philippines). The females of Bowie neukoeln Jäger, 2022 and Bowie shakeit Jäger, 2022, and the male of B. hosei (F.O. Pickard-Cambridge, 1897) are redescribed. Detailed descriptions, digital photographs and a distributional map are provided.
The Copelatus latipes species complex is introduced for Oriental species of Copelatus Erichson, 1832 belonging to the C. irinus group and characterised by the presence of processes on the ventral side of the median lobe of the aedeagus, forming a "beak-shaped" structure. The complex comprises six species, including two newly described taxa: Copelatus bezdeki Sheth, Ghate & Hájek, 2018 (India), C. brivioi Rocchi, 1976 (Bangladesh, India, Nepal), C. kopetzi sp. nov. (Nepal), C. lanxangensis sp. nov. (Laos), C. latipes Sharp, 1882 (Cambodia, Indonesia, Laos, Malaysia) and C. schereri Wewalka, 1981 (India, Sri Lanka). All species are diagnosed, and their habitus and male genitalia are illustrated.
From the Malay Peninsula (West Malaysia) 18 species of the genus Laena Dejean, 1821 are known so far. Additional two species are described herein as new: L. johoria sp. nov. and L. ledangica sp. nov. They originate exclusively from the southernmost, hitherto less explored Malaysian Federal State of Johor. Some new records of known Malaysian species are also listed.
Concern for megafauna is increasing among scientists and non-scientists. Many studies have emphasized that megafauna play prominent ecological roles and provide important ecosystem services to humanity. But, what precisely are 'megafauna'? Here, we critically assess the concept of megafauna and propose a goal-oriented framework for megafaunal research. First, we review definitions of megafauna and analyse associated terminology in the scientific literature. Second, we conduct a survey among ecologists and palaeontologists to assess the species traits used to identify and define megafauna. Our review indicates that definitions are highly dependent on the study ecosystem and research question, and primarily rely on ad hoc size-related criteria. Our survey suggests that body size is crucial, but not necessarily sufficient, for addressing the different applications of the term megafauna. Thus, after discussing the pros and cons of existing definitions, we propose an additional approach by defining two function-oriented megafaunal concepts: 'keystone megafauna' and 'functional megafauna', with its variant 'apex megafauna'. Assessing megafauna from a functional perspective could challenge the perception that there may not be a unifying definition of megafauna that can be applied to all eco-evolutionary narratives. In addition, using functional definitions of megafauna could be especially conducive to cross-disciplinary understanding and cooperation, improvement of conservation policy and practice, and strengthening of public perception. As megafaunal research advances, we encourage scientists to unambiguously define how they use the term 'megafauna' and to present the logic underpinning their definition.
The taxonomy of the little-known cricket genus Changiola from the subfamily Pteroplistinae is reviewed here. This genus consisted of three species, two from Malay Peninsula and one from Indochina. Here, we describe a new species from Borneo, the first from the island: Changiola sarawakensis n. sp. We also provide a key to the species, although it is likely that more species will be added to this genus with more sampling in the region.
The concentrations of cadmium, copper, zinc and lead, in the total soft tissues of green-lipped mussel Perna viridis of a wide range of sizes (2-11 cm), were determined from a population at Pasir Panjang. The metal contents (μg per individual) and concentrations (μg per g) of cadmium, lead, copper and zinc were studied in P. viridis to find the relationships with body sizes. Smaller and younger mussels showed higher concentrations (μg per g) of Cd, Pb and Zn than the larger and older ones. The results of the present study showed that the plotting of the metal content, against dry body flesh weight on a double logarithmic basis, gave good positive straight lines; this observation is in agreement with Boyden’s formula (1977). This indicated that P. viridis showed a different physiological strategy for each metal being studied, which is related to age.