Land snails and slugs of Bau limestone hills, Sarawak (Malaysia, Borneo), with the descriptions of 13 new species Author Marzuki, Mohammad Effendi bin Institute of Biodiversity and Environmental Conservation, Universiti Malaysia Sarawak, 94300, Kota Samarahan, Sarawak, Malaysia & Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Jalan UMS, 88450, Kota Kinabalu, Sabah, Malaysia fendiemz@gmail.com Author Liew, Thor-Seng https://orcid.org/0000-0002-9437-5924 Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Jalan UMS, 88450, Kota Kinabalu, Sabah, Malaysia thorsengliew@gmail.com Author Mohd-Azlan, Jayasilan Institute of Biodiversity and Environmental Conservation, Universiti Malaysia Sarawak, 94300, Kota Samarahan, Sarawak, Malaysia text ZooKeys 2021 2021-04-27 1035 1 113 http://dx.doi.org/10.3897/zookeys.1035.60843 journal article http://dx.doi.org/10.3897/zookeys.1035.60843 1313-2970-1035-1 ED19022EA1704DB79587FEFE15D07854 4C2258D4EE6754488B9280D3AB0447A1 Opisthostoma brachyacrum lambi (Vermeulen, 1991) Figure 10C Opisthostoma lambii Vermeulen, 1991a: 155. Type locality. "SARAWAK. 1st Div.: W of Kpg. Lobang Batu 12.5 km S of Tebakang". Material examined. Gunung Sebayat: ME 8002. Bukit Sekunyit: ME 0311. Gunung Doya: ME 0287, ME 9082, ME 9246. Gunung Kapor: ME 0281, ME 0310, ME 2875, ME 8978, ME 9003, ME 9077. Kampung Padang Pan: ME 6670. Lobang Angin: ME 9106, ME 9147, ME 9224. Distribution in Borneo. Sarawak: Kuching, Serian and Kapit divisions. Sabah: Interior and West Coast divisions. Endemic to Borneo. Remarks. Living snails were observed foraging among leaf litter and plant debris near the cliff in a lowland limestone forest.