The Southeast Asian Journal of Tropical Biology Vol. 31 No. 2, 2024: 169 - 180 DOI: 10.11598/btb.2024.31.2.1874 ISSN: 0215-6334 | e-ISSN: 1907-770X 169 CONSERVATION STATUS OF TREE SPECIES OF THE FRESHWATER SWAMP FOREST, PERAK TENGAH, MALAYSIA Liliwirianis Nawi1*, Mohd Nazip Suratman2, Farida Zuraina Mohd Yusof3, Abdul Latiff Mohamad4 1Faculty of Applied Sciences, Universiti Teknologi MARA Pahang, Bandar Tun Abdul Razak Jengka 26400, Malaysia. 2Institute for Biodiversity and Sustainable Development, Universiti Teknologi MARA (UiTM), Shah Alam 40450, Malaysia. 3Faculty of Applied Sciences, Universiti Teknologi MARA (UiTM), Shah Alam 40450, Malaysia. 4Department of Biological Science and Biotechnology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia. ARTICLE HIGLIGHTS • Approximately 3,364 tree individuals with a diameter at breast height (dbh) of 10.0 cm and above were assessed in the Perak Tengah freshwater swamp forest. • The study has recognised 58 species identified are new to Perak. • 72 tree species are listed as endemic, and 194 species are listed in the Red List of Threatened Species by The International Union for Conservation of Nature (IUCN). • This study mphasize the need to preserve ecology and mitigate threats. ABSTRACT The forests of Peninsular Malaysia have long been recognized as a significant home of endemic species. The purpose of this study was to assess the endemism and conservation status of tree species present in the Perak Tengah freshwater swamp forest. A total of 150 plots (20 m × 20 m) were established in the study area using a random sampling design. Approximately 3,364 tree individuals with diameter at breast height (dbh) of 10.0 cm and above were enumerated in all plots. In the study area, 58 species identified are new to Perak, 72 tree species are listed as endemic, and 194 species are listed in the Red List of Threatened Species by IUCN. Thus, it is crucial to preserve the ecology and lessen the impact of threats in the Perak Tengah freshwater swamp forest, which is home to numerous endemic and endangered species. Keywords: endangered, endemic, freshwater swamp forest, malaysia, perak, threatened Article Information Received 25 January 2023 Revised 23 March 2024 Accepted 22 May 2024 *Corresponding author, e-mail: liliwirianis@uitm.edu.my Research Article INTRODUCTION Malaysia has lost a substantial amount of forest due to cash-crop plantations (oil palm, rubber, and acacia, including fallow lands) and urban expansion (Huang & Oey 2019). For the past 29 years, nearly 16% (189,423 ha) of Perak’s forest cover has disappeared due to anthropogenic activities (Kanniah & Siong 2017; Jaafar et al. 2020). According to the Fifth National Report of the Convention on Biological Diversity (2020), over 80% of the larger genera are endemic. Most endemic species are vulnerable to extinction because they are only restricted to one area with a specific microclimate. Malaysia is estimated to possess 15,000 species of flora, with 8,300 species found in Peninsular Malaysia. There are currently at least 9,030 vascular plant taxa in Peninsular Malaysia, made up of 1,651 genera and 248 families, with at least 149 new taxa identified since 2005 (Yong et al. 2021). Malaysia has also recorded approximately 2,500 species of endemic vascular plants (Saw & Chung 2015). Rare species are becoming the most significant concern for conservationists due to the risk of extinction. Species can be considered rare when they have small population sizes, restricted geographical ranges, or narrow habitat tolerances. When combined, these characteristics define several forms of rarity and different levels of extinction risk (Kruckeberg & Rabinowitz 1985). https://doi.org/10.11598/btb.2024.31.2.1741 BIOTROPIA Vol. 31 No. 2, 2024 170 Rare species have greater sensitivity to both natural- and human-induced disturbances, such as overexploitation, habitat loss, and global environmental changes (Davies et al. 2004). Meanwhile, from the ecological aspect, endemism refers to the occurrence of any taxonomic entity (species, genus, or family) within a restricted and entirely defined area. Endemism is essential to ecologists, biogeographers, and evolutionary biologists in general. Endemics can be old (palaeoendemics) or new (neoendemics). Endemic species are an important target of global conservation efforts. As for species richness, a smaller amount of total area will need to be conserved if endemism patterns among taxa are correlated. Generally, the number of taxa endemic to a particular area increases with size and geographic isolation (Anderson 1994). Extinction will result in ecological loss and disturbance to the equilibrium of the forest. A better understanding of the rarity types and their differences needs to be considered for better conservation planning and strategies. Thus, the establishment of the International Union for Conservation of Nature (IUCN) aims to influence, encourage, and assist societies to conserve diversity and to ensure that any use of natural resources is equitable and ecologically sustainable. The study aimed to assess the endemism and conservation status of species found in the Perak Tengah freshwater swamp forest. Due to the ecology and drainage, freshwater swamp forests are particularly vulnerable to outside influences. Although endemic species are not necessarily rare or threatened by extinction, species typically become rare before going extinct (Kruckeberg & Rabinowitz 1985; Dobson et al. 1995). Endemic species, especially those with narrow distributions, as in this freshwater swamp forest, are particularly vulnerable to extinction resulting from habitat disturbance and other threats (Kiew et al. 2017; Kiew & Rahman 2021). MATERIALS AND METHODS Study Area The study area was located at the freshwater swamp forest remnant located in the District of Perak Tengah, Bandar Sri Iskandar. The area of Perak Tengah District is about 12,205 ha and comprises 11 subdistricts. The study areas were located at the Universiti Teknologi MARA (UiTM) Perak Sri Iskandar Forest (4°21'31.1" N; 100°57'12.7" E), Universiti Teknologi Petronas (UTP) Tronoh Forest (4°22'49.9" N; 100°57'44.8" E), and the Parit Forest Reserve, Parit (4°24'13.9" N; 100°56'03.7" E), as shown in Figure 1. The forest is surrounded by secondary forests with urban development leaving isolated freshwater swamp forest areas. Freshwater swamp forest is a unique habitat that occurs in permanently flooded soil. The forest comprises stilt roots, knee roots, and plank-like sinuous buttresses, which are common features of tree species found in freshwater swamp forests. The mean monthly temperatures for the study area ranged from 26.5 °C to 28.7 °C with an annual rainfall of 245.6 cm. Figure 1 Map of study area at Perak Tengah, Perak Notes: (1) UiTM Perak, Sri Iskandar Forest; (2) UTP, Tronoh Forest; and (3) Parit Forest Reserve, Parit. Endemism and Conservation Status of Tree Species of Freshwater Swamp Forest, Perak, Malaysia - Liliwirianiset. al. 171 Data Collection The study plots were established using random sampling from May 2011 to April 2015. A total of 150 plots of 20 × 20 m each were established in the study area, totalling 6 ha. All trees with a diameter breast height (DBH) of 10 cm or greater were measured using a diameter tape. Leaves and fruit specimens from the trees with DBH of more than 10 cm were collected, recorded, and kept in the Universiti Kebangsaan Malaysia (UKM) Herbarium. Woody climbers and creepers were excluded from the study. The trees were identified to the species level using the existing specimens in the UKM Herbarium, existing taxonomic keys (Whitmore 1972; 1973), and the assistance of an experienced botanist from UKM and the Pahang Forestry Department. The nomenclature of the species was determined according to Turner (1995) and the International Plant Name Index (IPNI). Meanwhile, specimens that could not be matched with herbarium specimens were only identified up to the genus or family level. Species New Records, Endemic and Conservation Status New records and endemic species were listed and referred to according to Turner (1995) and Chua et al. (2010). Conservation status was determined based on the IUCN Red List of Threatened Species version 2020.1 (IUCN Red List of Threatened Species, 2020) and Yong et al. (2021). In addition, the Dipterocarpaceae family was also compared using the Malaysian Plant Red List (Saw et al. 2010). RESULTS AND DISCUSSION New Records of Species About 58 of 624 tree species (9.3%) in the freshwater swamp forest in Perak Tengah were listed as new species to Perak State based on Turner (1995) (Table 1). The new records in Perak State may be due to insufficient sample collection from the past. The freshwater swamp forest also faces threats from deforestation and urban expansion, leading to habitat reduction (Saw 2010). On top of that, in Peninsular Malaysia, habitat degradation and loss pose the biggest challenge to plant populations. The primary causes of habitat loss include changes in land use for agricultural, residential, and commercial development (Yong et al. 2021). The discovery of these 58 species during these two decades may offer signs of hope for Malaysia’s local biodiversity. It also shows that the knowledge about these tree species is still far from satisfactory and complete. Interestingly, some of the species listed in Table 1 were only found in one state. For example, Castanopsis foxworthyi and Helicia maxwelliana were found only in Terengganu. However, the species was also found in the study area, i.e., the freshwater swamp forest. On top of that, theoretically, C. foxworthyi also occupies lowland peat-swamp, heath forest, and upper montane forest, while H. maxwelliana is found in the montane forest at 1,200 m. Nishimura et al. (2008) revealed that some species from the Fagaceae family showed a random distribution pattern. Moreover, Palaquium confertum, Syzygium polyanthum var. polyanthum, S. polyanthum var. sessile, and Trigonostemon polyanthus were only found in Johore, Croton kelantanicus was found in Kelantan, and Syzygium claviflorum var. riparium which were documented in Pahang can also be found in the freshwater swamp forest of Perak Tengah. Endemic Species of Peninsular Malaysia An endemic species usually grows and is found in a specific area and has restricted distribution. A total of 72 tree species from 56 families encountered in the Perak Tengah freshwater swamp forest were listed as endemic based on Turner (1995) and Chua et al. (2010) (Table 2). From the list presented in Table 2, 12 of them are recorded as new in Perak. A previous study in Perak Tengah revealed that Vatica flavida was left with a small number of individuals (249 individuals) due to the loss of large tracts of freshwater swamp forests followed by forest fragmentation. Shorea hemsleyana ssp. hemsleyana and Hopea apiculata were also threatened since their populations have decreased and their habitat has been degraded. It can be concluded that the most significant impact on the habitat has been from activities related to the development and human activities that lead to the depletion of their habitat (Liliwirianis 2021). BIOTROPIA Vol. 31 No. 2, 2024 172 No. Species Known distribution 1 Actinodaphne pruinosa Kd, Pn, Sl, Ns, Ml, Sp 2 Alseodaphne bancana Sl, Jh, Sp. 3 Alstonia scholaris Kd, Kl, Tg, Ph, Sl, Ml, Jh. 4 Anacolosa frutescens Kd, Ph, Sl, Ns, Ml, Jh, Sp. 5 Aporosa frutescens Kd, Pn, Kl, Ph, Jh, Sp. 6 Aporosa microstachya Kd, Tg 7 Ardisia korthalsiana Tg, Ph, Ml, Jh. 8 Artocarpus kemando Tg, Ph, Sl, Jh, Sp. 9 Calophyllum ferrugineum var. ferrugineum Jh, Sp. 10 Calophyllum rubiginosum Sl, Ns, Ml, Jh, Sp. 11 Calophyllum soulattri Ps, Kd, Pn, Kl, Ph, Ns, Ml, Jh. 12 Canarium megalanthum Kd, Ph, Ns, Jh. 13 Canthium cochinchinense P. Langkawi, Tg. 14 Castanopsis foxworthyi Tg. 15 Chrysophyllum roxburghii Kd, Ph, Sl,, Ns, Ml, Jh, Sp. 16 Croton kelantanicus Kl 17 Cryptocarya ferrea Kd, Kl, Tg, Ph, Sl. 18 Cryptocarya zollingeriana Kl, Sl. 19 Dillenia reticulata var. reticulata Ml 20 Diospyros ismailii Kd, Tg, Ph, Sl, Ns, Jh; 21 Diospyros montana P. Langkawi. 22 Diospyros undulata Ps, Kd, P. Langkawi. 23 Durio carinatus Ph, Jh. 24 Elaeocarpus nitidus var. velutinus Kl, Ph, Jh; 25 Helicia maxwelliana Tg. 26 Horsfieldia penangiana Pn, Ph, Sl. 27 Hydnocarpus kunstleri var. tomentosa Tg, Pk, Ph, Sl, Jh; 28 Knema latericia ssp. ridleyi Tg, Jh, Sp. 29 Litsea erectinervia Tg, Ph, Sl, Ml, Sp. 30 Litsea magnifica Pn, Kl, Ph, Ml, Jh 31 Lophopetalum pallidum Kd, Pn, Sl, Ns, Ml, Jh. 32 Madhuca decipiens Jh, Sp. 33 Madhuca selangorica Ph, Sl, Ns; 34 Neo-uvaria acuminatissima Pn, Ph, Sl. 35 Neo-uvaria foetida Tg, Ns, Ml. 36 Nephelium cuspidatum var. cuspidatum Tg, Sl, Ns, Jh 37 Nephelium cuspidatum var. eriopetalum Kl, Ph, Sl, Ns, Jh. 38 Palaquium confertum Jh. 39 Palaquium leiocarpum Kl, Tg. 40 Palaquium macrocarpum Sl, Jh. 41 Palaquium obovatum Kd, Pn, Kl, Tg, Ph, Sl, Ns, Ml, Jh, Sp. 42 Parishia maingayi Tg, Pk, Ph, Sl, Jh, Sp. No. Species Known distribution 43 Pimelodendron macrocarpum Sl, Ml, Jh. 44 Polyalthia cinnamomea Ps, Kd, Pn, Kl, Tg, Ph, Sl, Ns, Ml, Jh. 45 Pternandra galeata Ph, Jh. 46 Rennellia microcephala Kd, Kl, Tg, Ph; 47 Santiria rubiginosa var. nana Sl. 48 Schoutenia accrescens ssp. borneensis Ulu Endau, Jh. 49 Sterculia rubiginosa var. setistipula Sl. 50 Syzygium anisosepalum Kd, Ph, Sl, Ns, Ml; 51 Syzygium attenuatum ssp. attenuatum var. attenuatum Kd, Pn, Ph, Sl, Ml, Jh, Sp. 52 Syzygium claviflorum var. riparium Ph 53 Syzygium polyanthum var. polyanthum Jh 54 Syzygium polyanthum var. sessile Jh 55 Syzygium scortechinii var. scortechinii Tg, Ph, Sl, Ns, Jh; 56 Toona sureni Ps, P. Langkawi, Kd, Pn, Kl, Ph, Sl, Jh. 57 Trigonostemon polyanthus Jh. 58 Urophyllum corymbosum Ps, Ph, Sl, Ns, Jh, Sp. Notes: Kd = Kedah; Pn = Penang; Sl = Selangor; NS = Negeri Sembilan; Ml = Melaka; Sp. = Singapore; Jh = Johore; Tg = Terengganu; Kl = Kelantan; Ps = Perlis; Ph = Pahang. No. Endemic species Total individuals found Distribution 1 Actinodaphne pruinosa* 3 Kd, Pn, Sl, Ns, Ml, Sp 2 Alangium ridleyi 1 Kd, Pn, Tg, Pk, Ph, Sl, Ns, Ml 3 Alphonsea kingii 2 Pk 4 Alphonsea maingayi 1 Pk, Sl, Ns, Ml, Jh, Sp 5 Aporosa selangorica 1 Kd, Pk, Ph, Sl 6 Baccaurea griffithii 16 Throughout 7 Baccaurea polyneura 2 Pk, Ml; 8 Beilschmiedia insignis 1 Kl, Pk, Ph, Sl 9 Beilschmiedia pahangensis 1 Kl, Pk, Ph 10 Calophyllum subsessile 2 Pk 11 Calophyllum ferrugineum var. oblongifolium 4 Kl, Tg, Pk, Ph, Sl, Ns, Ml, Jh 12 Calophyllum wallichianum var. wallichianum 6 Kd, Pn, Kl, Pk, Ns 13 Canarium pseudosumatranum 1 Ps, Kd, Pk, Ph, Sl, Ns 14 Casearia clarkei var. clarkei 5 Pn, Pk, Sl, Ml, Sp Table 1 List of new tree species to Perak State at Perak Tengah Freshwater Swamp Forest, Perak Table 2 List of tree species found at Perak Tengah Freshwater Swamp Forest that are endemic to Peninsular Malaysia Endemism and Conservation Status of Tree Species of Freshwater Swamp Forest, Perak, Malaysia - Liliwirianiset. al. 173 No. Endemic species Total individuals found Distribution 15 Cinnamomum mollissimum 2 Pn, Kl, Tg, Pk, Ph, Sl, Ns, Ml, Jh 16 Croton erythrostachys 1 Tg, Pk, Ph, Sl, Ns, Ml, Jh 17 Croton kelantanicus* 1 Sg Ketil, Kl 18 Cyathocalyx pruniferus 4 Kl, Tg, Pk, Ph, Sl, Ml, Jh 19 Dacryodes kingii 1 Throughout 20 Dacryodes puberula 1 Pk, Ph, Ns, Ml 21 Dillenia reticulata var. reticulata* 8 Ml 22 Diospyros argentea 3 Sp, Tg, Ml, Pk, Sl, Ph, Ns, Jh, 23 Diospyros ismailii* 2 Kd, Tg, Ph, Sl, Ns, Jh 24 Diospyros scortechinii 1 Kl, Tg, Pk, Ph, Ns 25 Diospyros singaporensis 7 Kd, Pk, Ph, Sl, Ns, Ml, Jh 26 Elaeocarpus nitidus var. velutinus* 1 Kl, Ph, Jh 27 Elaeocarpus nitidus var. wrayi 1 Tg, Pk, Ph 28 Enicosanthum fuscum 6 Pk, Ph 29 Enicosanthum macranthum 3 Pk 30 Garcinia uniflora 1 Pk, Ph 31 Gentingia subsessilis 1 Pk, Ph, Sl 32 Gluta curtisii 1 Kd, Kl, Pn, Pk, Ph, Sl, Jh 33 Hydnocarpus filipes 1 Tg, Pk, Ph, Sl 34 Hydnocarpus kunstleri var. tomentosa 1 Tg, Pk, Ph, Sl, Jh; 35 Knema oblongifolia 1 Tg, Pk, Ph, Sl 36 Lithocarpus curtisii 4 Pn, Kl, Tg, Pk, Ph, Sl 37 Litsea curtisii 1 Kd, Pn, Pk, Sl, Jh 38 Litsea wrayi 1 Kd, Pk, Sl, Ns 39 Madhuca selangorica* 1 Ph, Sl, Ns 40 Mallotus griffithianus 2 Throughout 41 Mallotus penangensis 1 Throughout 42 Melanochyla nitida 1 Pn, Pk; 43 Mesua lepidota var. parviflora 1 Tg, Pk, Sl, Ml, Jh 44 Mesua nuda 1 Kd, Pn, Kl, Tg, Pk, Ph, Sl, Ns, Ml, Jh 45 Nephelium costatum 58 Pk, Ph, Ns, Ml, Kd, Kl, Jh 46 Nephelium hamulatum 9 Kd, Kl, Tg, Pk, Ph, Sl, Ns, Ml, Jh 47 Palaquium maingayi 2 Kd, Kl, Pk, Ph, Sl, Ns, Ml, Jh 48 Palaquium oxleyanum 1 Pk, Ph, Sl, Sp 49 Payena maingayi 7 Kd, Pn, Tg, Pk, Ph, Sl, Ns, Ml, Jh, Sp No. Endemic species Total individuals found Distribution 50 Pellacalyx saccardianus 12 Widespread 51 Pentace perakensis 1 Pk 52 Popowia fusca 1 Pk, Ph, Sp 53 Prunus malayana 6 Tg, Ph, Pk 54 Psydrax maingayi 5 Tg, Ph, Pk, Sl, Ns, Ml, Jh 55 Ptychopyxis caput-medusae 17 Kl, Tg, Pk, Ph, Sl, Ns, Ml, Sp 56 Rennellia microcephala* 1 Kd, Kl, Tg, Ph 57 Santiria ridleyi 5 Gg Keladang, Pk 58 Sarcotheca laxa var. laxa 52 Ps, Kd, Kl, Tg, Pk 59 Sarcotheca monophylla 9 Pk, Ph, Sl, Ml 60 Sauropus suberosus 1 Pk, Ph 61 Shorea singkawang ssp. singkawang 1 Tg, Ph, Pk 62 Streblus perakensis 3 Pk, Ph 63 Syzygium anisosepalum* 3 Kd, Ph, Sl, Ns, Ml 64 Syzygium castaneum 2 Pk, Jh 65 Syzygium claviflorum var. riparium* 1 Sg Tahan, Ph 66 Syzygium perakense 3 Pk, Sl 67 Syzygium polyanthum var. polyanthum* 1 Sg Kayu, Jh 68 Syzygium polyanthum var. sessile* 2 Jh 69 Syzygium scortechinii var. scortechinii* 1 Tg, Ph, Sl, Ns, Jh 70 Vatica flavida 6 Pk 71 Vatica pallida 1 Pn, Pk Notes: Pk = Perak; Ml = Melaka; Kl = Kelantan; Ph = Pahang; Sl= Selangor; NS = Negeri Sembilan; Pn = Penang; Sp.= Singapore; Jh = Johore; Tg = Terengganu. *New record in Perak. Since species have a necessary minimum population size and distribution for optimum survival, extremely small residual populations of rare and endemic taxa may all be extinct. This is exacerbated by edge effects, which may include invasion and species composition alteration by more common species prevalent just outside this forest. Most studies identifying hotspots do not use the same criteria proposed at the global scale (Major 1988), and endemicity is often the only criterion used (Huang et al. 2012; Kraf et al. 2010). This is because endemic species are often explored better in a particular area than the complete flora or the threats. Furthermore, since narrowly endemic species are often endangered, endemic taxa are an important category for conservation (Laffan et al. 2013)both within their region and at continental scales. We do this using the plant family Myrtaceae in relation to the globally important Greater Blue Mountains World BIOTROPIA Vol. 31 No. 2, 2024 174 Heritage Area (GBMWHA). Additionally, since their numbers and distribution are well-known and because they sustain virtually all animal life, plants have been employed as indicators of species endemism. IUCN Conservation Status A total of 2,830 plant species in Malaysia are listed in the IUCN Red List of Threatened Species version 2020.1 (The IUCN Red List of Threatened Species, 2020). Only one species is listed in the extinct (EX) category, one species is listed as extinct in the wild (EW), 166 species are listed as critically endangered (CR), 248 species are categorized as endangered (EN), 579 species are included in the vulnerable category (VU), 194 species are classified as near threatened (NT), 102 species are Table 3 The IUCN conservation status of tree species in Perak Tengah freshwater swamp forest categorized as lower risk/conservation dependent (LR/ CD), 98 species are considered in the status of data deficient (DD), and 1,440 species are classified as the least concern (LC; The IUCN Red List of Threatened Species, 2020). Species categorized as CR, EN, and VU are collectively referred to as threatened. All the species found in the study plots were compared with the IUCN Red List, with 194 of 624 tree species in the Perak Tengah freshwater swamp forest were found in the Red List of Threatened Species (Table 3). The study area comprises 7% of the listed plants in the IUCN for Malaysia. The Dipterocarpaceae family leads the number of threatened species with 22 species (46.8%), and the family comprises six species listed as CR. No. Family Species IUCN status 1 Anacardiaceae Gluta curtisii Lower risk/ least concern 2 Anacardiaceae Mangifera foetida Lower risk/ least concern 3 Anacardiaceae Mangifera magnifica Lower risk/ least concern 4 Anacardiaceae Melanochyla nitida Lower risk/ least concern 5 Anacardiaceae Pentaspadon motleyi Data Deficient 6 Anisophylleaceae Anisophyllea apetala Vulnerable 7 Annonaceae Alphonsea kingii Critically endangered 8 Annonaceae Alphonsea maingayi Lower risk/ least concern 9 Annonaceae Cyathocalyx pruniferus Lower risk/ least concern 10 Annonaceae Enicosanthum fuscum Near Threatened 11 Annonaceae Enicosanthum macranthum Vulnerable 12 Annonaceae Popowia fusca Lower risk/ least concern 13 Apocynaceae Alstonia scholaris Lower risk/ least concern 14 Apocynaceae Dyera costulata Lower risk/ least concern 15 Apocynaceae Hunteria zeylanica Lower risk/ least concern 16 Aquifoliaceae Ilex cymosa Lower risk/ least concern 17 Burseraceae Canarium hirsutum Lower risk/ least concern 18 Burseraceae Canarium littorale Lower risk/ least concern 19 Burseraceae Canarium pseudodecumanum Vulnerable 20 Burseraceae Canarium pseudosumatranum Lower risk: conservation dependent 21 Burseraceae Dacryodes incurvata Lower risk/ least concern 22 Burseraceae Dacryodes kingii Lower risk: conservation dependent 23 Burseraceae Dacryodes puberula Vulnerable 24 Burseraceae Dacryodes rostrata Lower risk/ least concern 25 Burseraceae Santiria apiculata var. apiculata Lower risk/ least concern 26 Burseraceae Santiria griffithii Lower risk/ least concern 27 Burseraceae Santiria laevigata Lower risk/ least concern 28 Burseraceae Santiria rubiginosa var. nana Vulnerable 29 Burseraceae Santiria rubiginosa var. rubiginosa Vulnerable 30 Celastraceae Bhesa paniculata Lower risk/ least concern Endemism and Conservation Status of Tree Species of Freshwater Swamp Forest, Perak, Malaysia - Liliwirianiset. al. 175 No. Family Species IUCN status 31 Celastraceae Bhesa robusta Lower risk/ least concern 32 Celastraceae Lophopetalum javanicum Lower risk/ least concern 33 Chloranthaceae Licania splendens Lower risk/ least concern 34 Chrysobalanaceae Parinari costata ssp. polyneura Lower risk/ least concern 35 Ctenolophonaceae Ctenolophon parvifolius Vulnerable 36 Dilleniaceae Dillenia reticulata var. psilocarpella Lower risk/ least concern 37 Dilleniaceae Dillenia reticulata var. reticulata Lower risk/ least concern 38 Dipterocarpaceae Anisoptera costata Endangered 39 Dipterocarpaceae Dipterocarpus crinitus Vulnerable 40 Dipterocarpaceae Dipterocarpus kerrii Endangered 41 Dipterocarpaceae Dipterocarpus kunstleri Critically endangered 42 Dipterocarpaceae Dipterocarpus semivestitus Critically endangered 43 Dipterocarpaceae Hopea apiculata Endangered 44 Dipterocarpaceae Neobalanocarpus heimii Endangered 45 Dipterocarpaceae Shorea curtisii ssp. curtisii Lower risk/ least concern 46 Dipterocarpaceae Shorea guiso Vulnerable 47 Dipterocarpaceae Shorea hemsleyana ssp. hemsleyana Vulnerable 48 Dipterocarpaceae Shorea hopeifolia Critically endangered 49 Dipterocarpaceae Shorea leprosula Near Threatened 50 Dipterocarpaceae Shorea macrantha Critically endangered 51 Dipterocarpaceae Shorea macroptera Lower risk/ least concern 52 Dipterocarpaceae Shorea materialis Critically endangered 53 Dipterocarpaceae Shorea multiflora Lower risk/ least concern 54 Dipterocarpaceae Shorea ovalis ssp. ovalis Endangered 55 Dipterocarpaceae Shorea parvifolia ssp. parvifolia Endangered 56 Dipterocarpaceae Shorea pauciflora Endangered 57 Dipterocarpaceae Shorea platycarpa Critically endangered 58 Dipterocarpaceae Shorea singkawang ssp. singkawang Vulnerable 59 Dipterocarpaceae Vatica flavida Critically endangered 60 Dipterocarpaceae Vatica pallida Endangered 61 Dipterocarpaceae Vatica pauciflora Vulnerable 62 Dipterocarpaceae Vatica stapfiana Vulnerable 63 Dipterocarpaceae Vatica umbonata Lower risk/ least concern 64 Dipterocarpaceae Vatica venulosa Critically endangered 65 Ebenaceae Diospyros apiculata Lower risk/ least concern 66 Ebenaceae Diospyros areolata Lower risk/ least concern 67 Ebenaceae Diospyros argentea Lower risk/ least concern 68 Ebenaceae Diospyros ismailii Lower risk/ least concern 69 Ebenaceae Diospyros scortechinii Lower risk/ least concern 70 Ebenaceae Diospyros singaporensis Lower risk/ least concern 71 Elaeocarpaceae Elaeocarpus petiolatus Lower risk/ least concern 72 Euphorbiaceae Baccaurea ramiflora Lower risk/ least concern 73 Euphorbiaceae Breynia vitis-idaea Lower risk/ least concern 74 Euphorbiaceae Claoxylon longifolium Lower risk/ least concern 75 Euphorbiaceae Croton kelantanicus Vulnerable 76 Euphorbiaceae Endospermum diadenum Lower risk/ least concern 77 Euphorbiaceae Mallotus penangensis Lower risk/ least concern 78 Euphorbiaceae Sapium baccatum Lower risk/ least concern 79 Fagaceae Lithocarpus curtisii Vulnerable BIOTROPIA Vol. 31 No. 2, 2024 176 No. Family Species IUCN status 80 Flacourtiaceae Hydnocarpus filipes Vulnerable 81 Flacourtiaceae Ryparosa javanica Lower risk/ least concern 82 Gnetaceae Gnetum gnemon var. gnemon Lower risk/ least concern 83 Guttiferae Calophyllum soulattri Lower risk/ least concern 84 Guttiferae Cratoxylum arborescens var. arborescens Lower risk/ least concern 85 Guttiferae Cratoxylum formosum Lower risk/ least concern 86 Guttiferae Cratoxylum maingayi Lower risk/ least concern 87 Guttiferae Garcinia scortechinii Lower risk/ least concern 88 Guttifereae Cratoxylum cochinchinense Lower risk/ least concern 89 Guttifereae Garcinia uniflora Lower risk/ least concern 90 Guttifereae Mesua nuda Lower risk/ least concern 91 Irvingiaceae Irvingia malayana Lower risk/ least concern 92 Lauraceae Actinodaphne pruinosa Lower risk/ least concern 93 Lauraceae Alseodaphne insignis Lower risk/ least concern 94 Lauraceae Beilschmiedia insignis Lower risk/ least concern 95 Lauraceae Beilschmiedia kunstleri Lower risk/ least concern 96 Lauraceae Beilschmiedia madang Lower risk/ least concern 97 Lauraceae Beilschmiedia pahangensis Lower risk/ least concern 98 Lauraceae Beilschmiedia wallichiana Vulnerable 99 Lauraceae Cinnamomum iners Lower risk/ least concern 100 Lauraceae Cinnamomum mollissimum Lower risk/ least concern 101 Lauraceae Cinnamomum porrectum Lower risk/ least concern 102 Lauraceae Cryptocarya ferrea Lower risk/ least concern 103 Lauraceae Litsea castanea Lower risk/ least concern 104 Lauraceae Litsea curtisii Endangered 105 Lauraceae Litsea elliptica Lower risk/ least concern 106 Lauraceae Litsea erectinervia Lower risk/ least concern 107 Lauraceae Litsea grandis Lower risk/ least concern 108 Lauraceae Litsea myristicifolia Lower risk/ least concern 109 Lauraceae Litsea sessiliflora Lower risk/ least concern 110 Lauraceae Litsea wrayi Lower risk/ least concern 111 Lauraceae Nothaphoebe panduriformis Lower risk/ least concern 112 Leguminosae Acacia mangium Lower risk/ least concern 113 Leguminosae Cynometra malaccensis Near threatened 114 Leguminosae Koompassia malaccensis Lower risk/ conservation dependent 115 Leguminosae Pongamia pinnata Lower risk/ least concern 116 Leguminosae Sindora coriacea Lower risk/ least concern 117 Meliaceae Aglaia elliptica Lower risk/ least concern 118 Meliaceae Aglaia argentea Lower risk/ least concern 119 Meliaceae Aglaia crassinervia Near Threatened 120 Meliaceae Aglaia odoratissima Lower risk/ least concern 121 Meliaceae Aglaia rubiginosa Near Threatened 122 Meliaceae Aglaia squamulosa Near Threatened 123 Meliaceae Sandoricum koetjape Vulnerable 124 Moraceae Antiaris toxicaria Lower risk/ least concern 125 Moraceae Artocarpus elasticus Lower risk/ least concern 126 Moraceae Ficus fistulosa var. fistulosa Lower risk/ least concern 127 Moraceae Ficus vasculosa Lower risk/ least concern 128 Myristicaceae Horsfieldia crassifolia Near Threatened Endemism and Conservation Status of Tree Species of Freshwater Swamp Forest, Perak, Malaysia - Liliwirianiset. al. 177 No. Family Species IUCN status 129 Myristicaceae Horsfieldia irya Lower risk/ least concern 130 Myristicaceae Horsfieldia penangiana Vulnerable 131 Myristicaceae Horsfieldia superba Near Threatened 132 Myristicaceae Horsfieldia tomentosa Near Threatened 133 Myristicaceae Knema conferta Lower risk/ least concern 134 Myristicaceae Knema curtisii var. paludosa Vulnerable 135 Myristicaceae Knema furfuracea Lower risk/ least concern 136 Myristicaceae Knema glauca Vulnerable 137 Myristicaceae Knema kunstleri Near Threatened 138 Myristicaceae Knema latericia ssp. ridleyi Lower risk/ least concern 139 Myristicaceae Knema laurina var. heteropilis Lower risk/ least concern 140 Myristicaceae Knema laurina var. laurina Lower risk/ least concern 141 Myristicaceae Knema oblongifolia Lower risk: conservation dependent 142 Myristicaceae Knema scortechinii Lower risk/ least concern 143 Myristicaceae Knema stenophylla Lower risk/ least concern 144 Myristicaceae Myristica iners Lower risk/ least concern 145 Myrsinaceae Ardisia korthalsiana Lower risk/ least concern 146 Myrtaceae Melaleuca cajuputi Lower risk/ least concern 147 Myrtaceae Rhodamnia cinerea Lower risk/ least concern 148 Myrtaceae Syzygium claviflorum var. claviflorum Lower risk/ least concern 149 Myrtaceae Syzygium claviflorum var. riparium Lower risk/ least concern 150 Myrtaceae Syzygium nervosum Lower risk/ least concern 151 Olacaceae Anacolosa frutescens Lower risk/ least concern 152 Olacaceae Ochanostachys amentacea Data deficient 153 Opiliaceae Champereia manillana Lower risk/ least concern 154 Oxalidaceae Sarcotheca laxa var. laxa Vulnerable 155 Oxalidaceae Sarcotheca monophylla Near Threatened 156 Proteaceae Helicia attenuata Lower risk/ least concern 157 Proteaceae Helicia petiolaris var. petiolaris Lower risk/ least concern 158 Rhizophoraceae Pellacalyx saccardianus Lower risk/ least concern 159 Rosaceae Prunus arborea var. arborea Lower risk/ least concern 160 Rosaceae Prunus malayana Lower risk/ least concern 161 Rosaceae Prunus polystachya Lower risk/ least concern 162 Rutaceae Acronychia pedunculata Lower risk/ least concern 163 Sapindaceae Arytera littoralis Lower risk/ least concern 164 Sapindaceae Glenniea penangensis Vulnerable 165 Sapindaceae Lepisanthes tetraphylla Lower risk/ least concern 166 Sapindaceae Nephelium costatum Vulnerable 167 Sapindaceae Nephelium hamulatum Vulnerable 168 Sapindaceae Nephelium lappaceum var. lappaceum Lower risk/ least concern 169 Sapindaceae Nephelium lappaceum var. pallens Lower risk/ least concern 170 Sapindaceae Pometia pinnata Lower risk/ least concern 171 Sapotaceae Chrysophyllum roxburghii Lower risk/ least concern 172 Sapotaceae Madhuca korthalsii Near Threatened 173 Sapotaceae Madhuca motleyana Near Threatened 174 Sapotaceae Madhuca selangorica Lower risk: conservation dependent 175 Sapotaceae Madhuca utilis Endangered 176 Sapotaceae Palaquium gutta Near Threatened 177 Sapotaceae Palaquium herveyi Near Threatened BIOTROPIA Vol. 31 No. 2, 2024 178 No. Family Species IUCN status 178 Sapotaceae Palaquium leiocarpum Near Threatened 179 Sapotaceae Palaquium maingayi Vulnerable 180 Sapotaceae Palaquium obovatum Lower risk/ least concern 181 Sapotaceae Payena lucida Near Threatened 182 Sapotaceae Payena maingayi Lower risk/ least concern 183 Sapotaceae Pouteria malaccensis Near Threatened 184 Sterculiaceae Sterculia parviflora Lower risk/ least concern 185 Thymelaeaceae Aquilaria malaccensis Vulnerable 186 Thymelaeaceae Gonystylus affinis Vulnerable 187 Tiliaceae Microcos laurifolia Lower risk: conservation dependent 188 Tiliaceae Microcos tomentosa Lower risk/ least concern 189 Tiliaceae Pentace curtisii Near Threatened 190 Tiliaceae Pentace perakensis Vulnerable 191 Tiliaceae Pentace triptera Lower risk/ least concern 192 Ulmaceae Gironniera subaequalis Lower risk/ least concern 193 Verbenaceae Callicarpa longifolia Lower risk/ least concern 194 Verbenaceae Vitex pinnata Lower risk/ least concern A total of 92 taxa of Peninsular Malaysia Dipterocarps are listed under the threatened category of the IUCN Red List (Saw et al. 2010). There are four species of Burseraceae; three species of Myristicaceae, Sapindaceae, and Sapotaceae; two species of Thymelaeaceae and Lauraceae; and one species of Anisophylleaceae, Annonaceae, Euphorbiaceae, Fagaceae, Flacourtiaceae Meliaceae, Oxalidaceae, and Tiliaceae. Thus, the threatened species of Dipterocarps found in the Perak Tengah freshwater swamp forest contributed to 23.9% of threatened Peninsular Malaysia Dipterocarp species. Liliwirianis (2021) reported that some Dipterocarp species residing in Perak Tengah comprise CR species. Unfortunately, the population size, to some extent, is extremely small, comprising less than 53 individuals, as befallen D. semivestitus. The tree number had decreased from the report by Saw (2010) over ten years. Saw (2010) reported that the freshwater swamp forest of the Lumut District, Perak, containing some of the rarest trees (D. semivestitus and V. flavida), is now confined to remnant areas. In the case of D. semivestitus, the species exists only as a remnant population in a 55-ha freshwater swamp forest at Universiti Teknologi MARA, Perak. To date, it is the only population that has been discovered in Peninsular Malaysia. An extensive survey of this area found only 53 individual trees. The species, which was once considered extinct, has been found in Perak, Malaysia. Endangered tree conservation is of utmost priority, as endangered species compete for limited suitable habitats with human development. Saw et al. (2010) reported that 92 taxa (56.1%) of Dipterocarpaceae were at some level of threat in Malaysia. In addition, Saw and Yen (2000) urged changes in land use patterns and rising demands on forest resources, and Malaysia’s attention to the sustainable use of forest resources now involves consideration of the entire problem of protection of all biodiversity. The IUCN Red List Categories and Criteria were developed using five criteria: population reduction, geographic range in the form of extent of occurrence or area of occupancy, small population size and decline, very small or restricted population, and quantitative analysis. Yong et al. (2021) confirmed that Perak is the second state with the highest number of threatened taxa, with 166 taxa. In addition, Chua et al. (2010) affirmed that Perak is the second highest state that comprises several threatened taxa (53 taxa) of Dipterocarps and perhaps is the most vulnerable as it has the greatest number of CR taxa (10), i.e., Dipterocarpus coriaceus, D. semivestitus, Hopea auriculata, Hopea bilitonensis, Parashorea globosa, S. hemsleyana ssp. Endemism and Conservation Status of Tree Species of Freshwater Swamp Forest, Perak, Malaysia - Liliwirianiset. al. 179 hemsleyana, Shorea lamellata, Shorea lumutensis, Shorea teysmanniana, and V. flavida. Our study showed that the freshwater swamp forest of the Perak Tengah study area consisted of some of the species: D. semivestitus, S. hemsleyana ssp. Hemsleyana, and V. flavida. CONCLUSION For a large field of research in freshwater swamp forests in Perak Tengah, the amount of endangered, new records, and vulnerable species is high. The results indicated that six species were documented as new for Perak, endemic and listed in the IUCN. The species were V. pallida, C. kelantanicus, Madhuca selangorica, Actinodahphne pruinosa, Dillenia reticulata var. reticulata, Diospyros ismailii, and S. claviflorum var. riparium. The species are also highly specialized since they are only confined to their special habitats. Thus, these unique groups would be at risk if the freshwater swamp forest and its adjacent regions are disturbed. Conservation of native and rare species could demand active protection, restoration, and high uniqueness of species-rich habitats and areas since the listed threatened species are currently not protected in the network of Totally Protected Areas (TPA) despite some of the study areas being monitored by the Forest Research Institute of Malaysia (FRIM). The Perak Tengah freshwater swamp forest has unique areas that house many endemic and endangered species needing of protection, and it is important to protect the environment and mitigate the threats. ACKNOWLEDGMENTS This work was supported by the research grants through the Fundamental Research Grant Scheme (FRGS) 600-RMI/FRGS 5/3 (41/2014) and UiTM’s Research Intensive Faculty (RIF) Grant (600-RMI/DANA 5/3/RIF (404/2012)). REFERENCES Anderson S. 1994. Area and endemism. The quarterly review of biology 69(4):451-71. Chua LSL, Suhaida M, Hamidah M, Saw LG. 2010. Malaysia Plant Redlist: Peninsular Malaysian Dipterocarpaceae. Research Pamphlet. No. 129. Kepong (MY): Forest Research Institute Malaysia. Davies KF, Margules CR, Lawrence JF. 2004. A synergistic effect puts rare, specialized species at greater risk of extinction. Ecology 85(1):265-71. Dobson FS, Yu J, Smith AT. 1995. The importance of evaluating rarity. Conservation Biology 9(6):1648-51. Fifth National Report to the Convention on Biological Diversity. 2020. Government of Malaysia Ministry of Natural Resources and Environment Fifth National Report to the Convention on Biological Diversity. www.nre.gov. my Huang J, Chen B, Liu C, Lai J, Zhang J, Ma K. 2012. Identifying hotspots of endemic woody seed plant diversity in China. Diversity and Distributions 18:673-88. DOI:10.1111/j.1472-4642.2011.00845.x Huang S, Oey L. 2019. Malay Archipelago forest loss to cash crops and urban expansion contributes to weaken the Asian summer monsoon: An atmospheric modeling study. J Clim 32(11):3189-3205. DOI:10.1175/JCLI-D-18-0467.1 International Plant Names Index [Internet]. 2020. Available from: https://www.ipni.org/ Jaafar WSWM, Maulud KNA, Kamarulzaman AMM, Raihan A, Sah SM, Ahmad A, Saad SNM, Azmi ATM, Syukri NKAJ, Khan WR. 2020. The Influence of Deforestation on Land Surface Temperature: A Case Study of Perak and Kedah, Malaysia.  Forests  11(6):670. doi.org/10.3390/ f11060670 Kanniah KD, Siong HC. 2017. Urban forest cover change and sustainability of Malaysian cities. Chem Eng Trans 56:673-8. Kessler M. 2002. The elevational gradient of Andean plant endemism: Varying influences of taxon-specific traits and topography at different taxonomic levels. J Biogeogr 29(9):1159-65. DOI: 10.1046/j.1365-2699.2002.00773.x Kiew R, Rafidah AR, Ong PT, Ummul Nazrah AR. 2017 Limestone treasures: Rare plants in Peninsular Malaysia- where they are, where they grow and how to conserve them. Malaysian Naturalist 71:32-41. Kiew R, Rahman RA. 2021. Plant diversity assessment of karst limestone, a case study of Malaysia’s Batu Caves. Nat Conserv 44:21-49. Kraf NJB, Baldwin BG, Ackerly DD. 2010. Range size, taxon age and hotspots of neo endemism in the California flora. Divers Distrib 16:403-13. Kruckeberg AR, Rabinowitz D. 1985. Biological aspects of endemism in higher plants. Ann Rev Ecol Syst 16(1):447- 79. Laffan SW, Ramp D, Roger E. 2013. Using endemism to assess representation of protected areas-the family Myrtaceae in the Greater Blue Mountains World Heritage Area. J Biogeogr 40(3):570-8. DOI:10.1111/jbi.12001 BIOTROPIA Vol. 31 No. 2, 2024 180 Liliwirianis N. 2021. Ecological Characteristics of Freshwater Swamp Forest, Perak Tengah, Malaysia [Thesis]. Bangi (MY): Universiti Kebangsaan Malaysia. Retrieved from Universiti Kebangsaan Malaysia. Liliwirianis N, Suratman MN, Tahir SZM. 2013. Conservation of the critically endangered tree species Dipterocarpus semivestitus in Malaysia. In BEIAC 2013. IEEE Business Engineering and Industrial Applications Colloquium. p.225-8. DOI:10.1109/BEIAC.2013.6560121 Major J. 1988. Endemism: A botanical perspective. In Myers AA, Giller PS (Editors). Analytical Biogeography: An Integrated Approach to the Study of Animal and Plant Distributions. London (UK): Chapman & Hall. p. 117- 46. Ng FSP, Low CM, Sanah MAN. 1990. Endemic trees of the Malay Peninsular. Research Pamphlet No. 106. Forest Research Institute Malaysia. Nishimura S, Yoneda T, Fujii S, Mukhtar E, Kanzaki M. 2008. Spatial patterns and habitat associations of Fagaceae in a hill dipterocarp forest in Ulu Gadut, West Sumatra. J Trop Ecol 24(5):535-50. Primack RB. 2002. Essentials of Conservation Biology. Sunderland (US): Sinauer Association. Saw LG. 2010. Vegetation of Peninsular Malaysia. In Kiew R, Chung RCK, Saw LG, Soepardmo E, Boyce PC (Editors). Flora of Peninsular Malaysia 2(1):21-45. Saw LG. 2010. Vegetation of Peninsular Malaysia. Seed Plant 1:1-41. Saw LG, Chung RCK. 2015. The Flora of Malaysia Projects. Rodriguesia 66(4):947-60. Saw LG, Yen SY. 2000. Conservation of Dipterocarpaceae in Peninsular Malaysia. J Trop For Sci 12(3):593-615. Turner IM. 1995. A Catalogue of the Vascular Plants of Malaya. Vol. 1. National Parks Board Singapore Botanic Garden. Walker BH. 1987. A general model of savanna structure and function. IUBS Monogr Ser. 1-12. Whitmore TC. 1972. Tree Flora of Malaya. Kuala Lumpur (MY): Longman Malaysia Sdn. Berhad. Whitmore TC. 1973. Tree Flora of Malaya. Vol. 2. Kuala Lumpur (MY):Longman Malaysia Sdn. Berhad. Yong WS, Chua LS, Lau KH, Siti Nur Fatinah K, Cheah YH, Yao TL, Rafidah AR, Lim CL, Syahida Emiza S, Ummul Nazrah AR, Nor Ezzawanis AT. 2021. Malaysia Red List: Plants of Peninsular Malaysia Part 1. Aslita, Kuala Lumpur.