taxonID	type	description	language	source
93C14AFA9C625F7F933B65684F2F8BD5.taxon	description	Fig. 2 A – D	en	Nurinsiyah, Ayu Savitri, Azizah, Salma Syifa, Prasetia, Ahmad Ghifari, Mujiono, Nova, Laitupa, Ibnu Wahab, Heryanto, (2025): Revisiting Bacan Island in the footsteps of Alfred Russel Wallace: unveiling the diversity of land snails (Mollusca, Gastropoda). ZooKeys 1233: 207-243, DOI: 10.3897/zookeys.1233.143563
93C14AFA9C625F7F933B65684F2F8BD5.taxon	diagnosis	Diagnosis. Shell with bulbous penultimate whorl and a distinct constriction on the dorsal part of the penultimate whorl. Radial ribs are distinct before and after the constriction, but on the penultimate whorl the ribs are less distinct and almost smooth with no spiral striae. One outer parietalis, three parallel palatalis, and three perpendicular palatalis are present beside the constriction inside the penultimate whorl. Colour almost white.	en	Nurinsiyah, Ayu Savitri, Azizah, Salma Syifa, Prasetia, Ahmad Ghifari, Mujiono, Nova, Laitupa, Ibnu Wahab, Heryanto, (2025): Revisiting Bacan Island in the footsteps of Alfred Russel Wallace: unveiling the diversity of land snails (Mollusca, Gastropoda). ZooKeys 1233: 207-243, DOI: 10.3897/zookeys.1233.143563
93C14AFA9C625F7F933B65684F2F8BD5.taxon	description	Description. The shell is small, elongated, and sinistral with a pointed apex, whitish cream in colour. The shell has 7 – 7.5 whorls that increase in size, with the body whorl being narrower than the penultimate whorl. There is a rapid increase in shell whorl size from the beginning of the teleoconch until the 5 th whorl, followed by a drastic constriction at the whorl 5.5 – 6, reducing the whorl size to that of the third whorl. The penultimate whorl (before constriction) is bulbous. The whorl size then increases again after the constriction for 1.5 whorls until the aperture. The umbilicus is closed. The protoconch is smooth, lacking ribs on the first whorl. Radial ribs are not sinuous but rather distinct, low, thin, and densely placed. The spacing between ribs increases from the beginning of the teleoconch until the 5 th or 6 th whorl, where the whorl size increases rapidly, causing the ribs to become less distinct and almost smooth. After the constriction, the ribs become more widely spaced before transitioning to a tighter spacing towards the aperture. Spiral striae are absent. A constriction is present on the penultimate whorl, with one outer parietalis, three parallel palatalis, and three perpendicular palatalis beside the constriction. The aperture is slightly oval and nearly rounded. Peristome simple because the outer and inner peristome fused. Operculum multispiral. Shell dimensions of the specimens (n = 16): H = 4.9 – 5.7 mm (mean 5.4 mm); D = 2.8 – 3.3 mm (mean 3.1 mm); ha = 2.0 – 2.4 mm (mean 2.2 mm); da = 1.8 – 2.3 mm (mean 2.1 mm).	en	Nurinsiyah, Ayu Savitri, Azizah, Salma Syifa, Prasetia, Ahmad Ghifari, Mujiono, Nova, Laitupa, Ibnu Wahab, Heryanto, (2025): Revisiting Bacan Island in the footsteps of Alfred Russel Wallace: unveiling the diversity of land snails (Mollusca, Gastropoda). ZooKeys 1233: 207-243, DOI: 10.3897/zookeys.1233.143563
93C14AFA9C625F7F933B65684F2F8BD5.taxon	distribution	Geographic distribution and habitat. The species has so far been recorded on Bacan Island, making it possibly endemic to this region. Specimens were collected from the karst forest habitat.	en	Nurinsiyah, Ayu Savitri, Azizah, Salma Syifa, Prasetia, Ahmad Ghifari, Mujiono, Nova, Laitupa, Ibnu Wahab, Heryanto, (2025): Revisiting Bacan Island in the footsteps of Alfred Russel Wallace: unveiling the diversity of land snails (Mollusca, Gastropoda). ZooKeys 1233: 207-243, DOI: 10.3897/zookeys.1233.143563
93C14AFA9C625F7F933B65684F2F8BD5.taxon	etymology	Etymology. The species name “ batu bacan ” refers to the famous Chrysocolla mineral / stone found on Bacan Island. Known for its striking beauty, the mineral shares a similar beauty to that of Diancta batubacan sp. nov.	en	Nurinsiyah, Ayu Savitri, Azizah, Salma Syifa, Prasetia, Ahmad Ghifari, Mujiono, Nova, Laitupa, Ibnu Wahab, Heryanto, (2025): Revisiting Bacan Island in the footsteps of Alfred Russel Wallace: unveiling the diversity of land snails (Mollusca, Gastropoda). ZooKeys 1233: 207-243, DOI: 10.3897/zookeys.1233.143563
