PEER-REVIEWED ARTICLE bioresources.com Siam et al. (2023). “Malaysian Wood Anatomy,” BioResources 18(1), 1232-1250. 1232 Wood Anatomical Features of Anacardiaceae from Malaysia Nordahlia Abdullah Siam, a, * Nor Azahana Abdullah, b Mohd Khairun Anwar Uyup, a Che Nurul Aini Che Amri, b Muhammad Amirul Aiman Ahmad Juhari, c and Noraini Talip d This study examined the anatomical features of Anacardiaceae from Malaysia. A total of 31 species from 13 genera of the family Anacardiaceae in Malaysia were obtained from Kepong Xylarium (KEPw), Forest Research Institute Malaysia. The genera in Anacardiaceae were distinguished based on anatomical features. The diagnostic anatomical features that were used to separate the genera are scalariform perforations plates present in Campnosperma, larger rays in Pentaspadon and Spondias, and radial canals in some genera. Mineral inclusion, i.e., crystals and silica also could be diagnostic features to distinguish the genera in Malaysian Anacardiaceae; silica was observed in Gluta, Parishia, and Swintonia. Anatomical features could be used as indicators to the other wood properties and lead to potential usage of timber in Anacardiaceae. However, the presence of druses in individual Toxicodendron succedaneum indicated its adaptation to the local microclimatic conditions. DOI: 10.15376/biores.18.1.1232-1250 Keywords: Anatomical features; Anacardiaceae; Potential usage; Wood identification Contact information: a: Forest Research Institute Malaysia, Kepong 52109 Selangor; b: Kulliyah of Science, International Islamic University Malaysia, Kuantan 25200 Pahang; c: Faculty of Forestry and Environment, University Putra Malaysia, Serdang 43400 Selangor; d: Faculty of Science and Technology, University Kebangsaan Malaysia, Bangi 43600 Selangor; * Corresponding author: nordahlia@frim.gov.my INTRODUCTION The importance of wood anatomical studies has been demonstrated in the classification and identification of plants based on certain diagnostic characteristics (Carlquist 2001; Akinloye et al. 2012; Macedo et al. 2014; Elamin 2018). Wood is identified by examining its anatomical features to determine its species, genera, or family. It is a necessary requirement to know the exact species, genera, or family in trade, customs, construction, and scientific research to avoid disputes in pricing, taxation, strength performance, and biological characteristics (Wheeler and Baas 1998; Lim et al. 2016). Wood identification is also important in forensics, archaeology, and paleontology (Wheeler and Baas 1998). There are several methods used to identify wood. Observation of the cross section of the wood using a hand lens of 10x magnification is sufficient. However, for timber groups that do not have distinct features, it is necessary to observe their microscopic features. Other important physical features, including colour, density, hardness, texture, grain, figure, and odour, are also useful in wood identification (Menon et al. 1993; Wheeler and Baas 1998; Nordahlia and Lim 2016). Generally, anatomical features are used as indicators of wood properties (Bowyer et al. 2003; Dewi and Supartini 2017; Noraini et al. 2019). Toong et al. (2014)