Additions to the knowledge of the land snails of Sabah (Malaysia, Borneo), including 48 new species

We present reviews of the Sabah (Malaysia, on the island of Borneo) species of the following problematical genera of land snails (Mollusca, Gastropoda): Acmella and Anaglyphula (Caenogastropoda: Assimineidae); Ditropopsis (Caenogastropoda: Cyclophoridae); Microcystina (Pulmonata: Ariophantidae); Philalanka and Thysanota (Pulmonata: Endodontidae); Kaliella, Rahula, (Pulmonata: Euconulidae); Trochomorpha and Geotrochus (Pulmonata: Trochomorphidae). Next to this, we describe new species in previously revised genera, such as Diplommatina (Diplommatinidae); Georissa (Hydrocenidae); as well as some new species of genera not revised previously, such as Japonia (Cyclophoridae); Durgella and Dyakia (Ariophantidae); Amphidromus, and Trachia (Camaenidae); Paralaoma (Punctidae); Curvella (Subulinidae). All descriptions are based on the morphology of the shells. We distinguish the following 48 new species: Acmella cyrtoglyphe, A. umbilicata, A. ovoidea, A. nana, A. subcancellata, A. striata, and Anaglyphula sauroderma (Assimineidae); Ditropopsis davisoni, D. trachychilus, D. constricta, D. tyloacron, D. cincta, and Japonia anceps (Cyclophoridae); Diplommatina bidentata and D. tylocheilos (Diplommatinidae); Georissa leucococca and G. nephrostoma (Hydrocenidae); Durgella densestriata, Dyakia chlorosoma, Microcystina microrhynchus, M. callifera, M. striatula, M. planiuscula, and M. physotrochus (Ariophantidae); Amphidromus psephos and Trachia serpentinitica (Camaenidae); Philalanka tambunanensis, P. obscura, P. anomphala, P. rugulosa, and P. malimgunung (Endodontidae); Kaliella eurytrochus, K. sublaxa, K. phacomorpha, K. punctata, K. microsoma, Rahula delopleura, (Euconulidae); Paralaoma angusta (Punctidae); Curvella hadrotes (Subulinidae); Trochomorpha trachus, T. haptoderma, T. thelecoryphe, Geotrochus oedobasis, G. spilokeiria, G. scolops, G. kitteli, G. subscalaris, and G. meristorhachis (Trochomorphidae).