The land area of Laos is composed of a large variety of undisturbed habitats, such as high mountainous areas, huge limestone karsts and the lower Mekong Basin. Therefore, Laos is expected to have a high species diversity, especially for the land snails. However, with respect to research on malacology, Laos is probably the least well-researched area for land snail diversity in Indochina (including Laos) over the past few centuries. The handful of species lists have never been systematically revised from the colonial period to the present, so these classifications are outdated. Herein we present the first comprehensive annotated checklist with an up-to-date systematic framework of the land snail fauna in Laos based on both field investigations and literature surveys. This annotated checklist is collectively composed of 231 nominal species (62 ‘prosobranch’ and 169 heterobranches), of which 221 nominal species are illustrated. The type specimens of 143 species from several museum collections and/or 144 species of newly collected specimens are illustrated. There are 58 species recorded as new to the malacofauna of the country, and two new replacement names are proposed asHemiplectalanxangnicaInkhavilay and Panha,nomen novum(Ariophantidae) andChloritiskhammouanensisInkhavilay and Panha,nomen novum(Camaenidae). Four recently described species of the genusAmphidromusfrom Laos, “thakhekensis”, “richgoldbergi”, “attapeuensis” and “phuonglinhae” are synonymized with previously described species. In addition, thirteen nominal species are listed as uncertain records that may or may not occur in Laos. This annotated checklist may inspire malacologists to carry on systematic research in this region.

Land snails were collected for the project ‘Conserving Myanmar’s Karst Biodiversity’ from the limestone karsts in Mon, Kayin, and Shan states and in the regions of Tanintharyi and Mandalay between 2015 and 2017, through cooperation with Fauna and Flora International (FFI) and the Forestry Department of Myanmar. Here, we report on a portion of the collection, and list 17 species from seven genera of the Hypselostomatidae microsnails. Three new species from two genera are described as Bensonella taiyaiorum Tongkerd & Panha, sp. nov., B. lophiodera Tongkerd & Panha, sp. nov., and Gyliotrachela aunglini Tongkerd & Panha, sp. nov. All new species are known only from the type locality in Shan State (Bensonella) and Kayin State (Gyliotrachela). A new combination of Acinolaemus dayanum and three newly recorded species, namely A. cryptidentatus, B. anguloobtusa and G. hungerfordiana are discussed. The low morphological variability of the widely distributed G. hungerfordiana is discussed, and two species are proposed for formal synonymisation. Constituting the first records for Myanmar, five species of Bensonella and two species of Acinolaemus were collected.

Hypselostomatidae is a large family of terrestrial pulmonate molluscs currently represented by 284 extant species, most confined to Southeast Asia. The current system of grouping species into genera is based on the morphology of the apertural barriers and the level of last whorl detachment. However, these characters overlap, challenging generic definitions. In this paper, these characters are evaluated and a novel classification proposed for hypselostomatid species belonging to the genera Anauchen (17 species), Bensonella (36 species), Boysidia (7 species, in part) and Hypselostoma (85 species). We assigned all species belonging to the genera Bensonella and Hypselostoma into two and four species groups respectively, which are characterised by combinations of morphological traits. Altogether 46 new species are described, seven species in Anauchen: A. crassus Gojšina, Hunyadi & Páll-Gergely, sp. nov., A. evanidus Gojšina & Páll-Gergely, sp. nov., A. grandiportus Gojšina, Grego & Páll-Gergely, sp. nov., A. obesus Gojšina, Hunyadi & Páll-Gergely, sp. nov., A. picasso Gojšina & Páll-Gergely, sp. nov., A. turritus Gojšina, Hunyadi & Páll-Gergely, sp. nov., A. jokaii Gojšina & Páll-Gergely, sp. nov.; 19 species in Bensonella: B. alycaeus Gojšina & Páll-Gergely, sp. nov., B. cardiostoma Gojšina, Vermeulen & Páll-Gergely, sp. nov., B. cristatissima Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. dha Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. dracula Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. exploda Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. fracta Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. microdentata Gojšina & Páll-Gergely, sp. nov., B. mitochondria Gojšina, Vermeulen & Páll-Gergely, sp. nov., B. mirabilis Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. montawa Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. multidentata Gojšina, A. Reischütz & Páll-Gergely, sp. nov., B. nitens Gojšina & Páll-Gergely, sp. nov., B. obex Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. perfecta Gojšina & Páll-Gergely, sp. nov., B. sericata Gojšina & Páll-Gergely, sp. nov., B. serrata Gojšina, Hunyadi & Páll-Gergely, sp. nov., B. spelaea Gojšina, Grego & Páll-Gergely, sp. nov., B. spinosa Gojšina, Hunyadi & Páll-Gergely, sp. nov.; 20 species in Hypselostoma: H. aquila Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. bubalus Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. circumcarinatum Gojšina, Auffenberg & Páll-Gergely, sp. nov., H. coriaceum Gojšina & Páll-Gergely, sp. nov., H. aenigma Gojšina, Grego & Páll-Gergely, sp. nov., H. fortunatum Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. fungus Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. geckophilum Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. iunior Gojšina & Páll-Gergely, sp. nov., H. ophis Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. platybasis Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. populare Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. sculpturatum Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. similare Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. sorormajor Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. sororminor Gojšina, Hunyadi & Páll-Gergely, sp. nov., H. torta Gojšina, Auffenberg & Páll-Gergely, sp. nov., H. vesovici Gojšina & Páll-Gergely, sp. nov., H. vicinum Gojšina, Auffenberg & Páll-Gergely, sp. nov., H. vujici Gojšina & Páll-Gergely, sp. nov. One replacement name is proposed: H. tertiusfrater Gojšina & Páll-Gergely, nom. nov. pro Boysidia salpinx F. G. Thompson & Dance, 1983, non Hypselostoma salpinx (van Benthem Jutting, 1961) (originally described as Gyliotrachela). Gyliotrachela and Antroapiculus are both treated as junior synonyms of Hypselostoma. An additional 28 species and subspecies are reassigned to the synonymies of other taxa.

Knowledge of Myanmar land snails is based on the late eighteenth to early twentieth century literature and many species need to be re-investigated, especially in the genera Macrochlamys Gray, 1847 and Sarika Godwin-Austen, 1907. In order to update this knowledge, this paper presents information on these two related genera based on new materials from south-eastern Myanmar. Fifteen species are recognised in the south-east of Myanmar. Of these, live material was available for eight Macrochlamys and Sarika species and these are described in full herein, based on data from the shell, external morphology and genitalia, including three species new to science (M. brachystia n. sp., S. concavata n. sp. and S. lopa n. sp.) and five species redescribed (M. aspides, M. kelantanensis, M. petasus, S. consepta and S. obesior). The remaining five species are known only from their shell morphology (M. cauisa, M. perpaula, M. poongee, M. salwinensis and S. birmana) and two species are known from genitalia (S. dugasti and S. resplendens). For these species the shells are figured and some taxonomic remarks are provided. http://www.zoobank.org/urn:lsid:zoobank.org:pub:58D2A9E7-50FD-49C2-B2F4-4D00457EA331

The collection of land caenogastropod snails in the genus Cyclophorus Monfort, 1810 housed in the Natural History Museum, London (NHM), includes 52 type lots. Lectotypes have been designated for 41 available species-level names to stabilize existing nomenclature, three previously designated lectotype, two holotypes, one paratype, two syntypes, one possible syntype and two paralectotypes are also listed. A complete catalogue of the Cyclophorus types in NHM, London is provided for the first time.