Contributions of a small collection of terrestrial microsnails (Pupilloidea, Hypselostomatidae) from Myanmar with description of three new species.

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 Bensonellataiyaiorum Tongkerd & Panha, sp. nov., B.lophiodera Tongkerd & Panha, sp. nov., and Gyliotrachelaaunglini 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 Acinolaemusdayanum 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.

Many roads to success: alternative routes to building an economic shell in land snails.

Land snails exhibit an extraordinary variety of shell shapes. The way shells are constructed underlies biological and mechanical constraints that vary across gastropod clades. Here, we quantify shell geometry of the two largest groups, Stylommatophora and Cyclophoroidea, to assess the potential causes for variation in shell shape and its relative frequency. Based on micro-computed tomography scans, we estimate material efficiency through 2D and 3D generalizations of the isoperimetric ratio, quantifying the ratios between area and perimeter of whorl cross-sections (2D) and shell volume and surface (3D), respectively. We find that stylommatophorans optimize material usage through whorl overlap, which may have promoted the diversification of flat-shelled species. Cyclophoroids are bound to a circular cross-section because of their operculum; flat shells are comparatively rare. Both groups show similar solutions for tall shells, where local geometry has a smaller effect because of the double overlap between previous and current whorls. Our results suggest that material efficiency is a driving factor in the selection of shell geometry. Essentially, the evolutionary success of Stylommatophora likely roots in their higher flexibility to produce an economic shell.

Five times over: 42 new Angustopila species highlight Southeast Asia's rich biodiversity (Gastropoda, Stylommatophora, Hypselostomatidae).

The Southeast Asian genus Angustopila, currently comprising 13 nominal species, encompasses the world's tiniest land snails. This work shows that there are far more species than previously suspected, and that this genus is in fact, a very speciose group of tiny snails widely distributed in Southeast Asia. Angustopila is revised based on type material of known species as well as 211 samples newly collected in China, Laos, Myanmar, Thailand and Vietnam. Altogether, 53 species and one subspecies are recognised, of which 42 species and subspecies are new to science: A.akrodon Páll-Gergely & Hunyadi, sp. nov., A.apiaria Páll-Gergely & Hunyadi, sp. nov., A.apiostoma Páll-Gergely & Vermeulen, sp. nov., A.apokritodon Páll-Gergely & Hunyadi, sp. nov., A.antidomedon Páll-Gergely & Hunyadi, sp. nov., A.babel Páll-Gergely & Vermeulen, sp. nov., A.bathyodon Páll-Gergely & Hunyadi, sp. nov., A.bidentata Páll-Gergely & Jochum, sp. nov., A.cavicola Páll-Gergely & Dumrongrojwattana, sp. nov., A.cicatricosa Páll-Gergely & Vermeulen, sp. nov., A.coprologosuninodus Páll-Gergely & Grego, ssp. nov., A.erawanica Páll-Gergely & Dumrongrojwattana, sp. nov., A.fratermajor Páll-Gergely & Vermeulen, sp. nov., A.fraterminor Páll-Gergely & Vermeulen, sp. nov., A.gracilis Páll-Gergely & Hunyadi, sp. nov., A.halongensis Páll-Gergely & Vermeulen, sp. nov., A.hyron Páll-Gergely & Vermeulen, sp. nov., A.maasseni Páll-Gergely & Vermeulen, sp. nov., A.majuscula Páll-Gergely & Hunyadi, sp. nov., A.margaritarion Páll-Gergely & Hunyadi, sp. nov., A.megastoma Páll-Gergely & Vermeulen, sp. nov., A.occidentalis Páll-Gergely & Hunyadi, sp. nov., A.oostoma Páll-Gergely & Vermeulen, sp. nov., A.papaver Páll-Gergely & Hunyadi, sp. nov., A.parallela Páll-Gergely & Hunyadi, sp. nov., A.prolixa Páll-Gergely & Hunyadi, sp. nov., A.pusilla Páll-Gergely & Hunyadi, sp. nov., A.pustulata Páll-Gergely & Hunyadi, sp. nov., A.quadridens Páll-Gergely & Vermeulen, sp. nov., A.rara Páll-Gergely & Hunyadi, sp. nov., A.reticulata Páll-Gergely & Hunyadi, sp. nov., A.somsaki Páll-Gergely & Hunyadi, sp. nov., A.steffeki Páll-Gergely & Grego, sp. nov., A.tetradon Páll-Gergely & Hunyadi, sp. nov., A.thersites Páll-Gergely & Vermeulen, sp. nov., A.tonkinospiroides Páll-Gergely & Vermeulen, sp. nov., A.tridentata Páll-Gergely & Hunyadi, sp. nov., A.tweediei Páll-Gergely & Hunyadi, sp. nov., A.uvula Páll-Gergely & Hunyadi, sp. nov., A.vandevenderi Páll-Gergely & Jochum, sp. nov., A.vitrina Páll-Gergely & Hunyadi, sp. nov., A.vomer Páll-Gergely & Hunyadi, sp. nov., A.werneri Páll-Gergely & Hunyadi, sp. nov. Angustopilasubelevata Páll-Gergely & Hunyadi, 2015 is moved to the synonymy of Angustopilaelevata (F. G. Thompson & Upatham, 1997), and A.singuladentis Inkhavilay & Panha, 2016 is a junior synonym of A.fabella Páll-Gergely & Hunyadi, 2015. Three species, namely A.elevata, A.fabella and A.szekeresi, are widespread over several hundred kilometres while some other species (A.huoyani, A.parallelasp. nov., A.cavicolasp. nov.) are known from just two sites a few hundred kilometres apart. All others are small range or single-site endemics. The reproductive anatomy of A.erawanicasp. nov. is described.

Revision of the Alycaeidae of China, Laos and Vietnam (Gastropoda: Cyclophoroidea) II: The genera Alycaeus and Pincerna.

This is the second part of the revision of Chinese, Lao and Vietnamese Alycaeidae (superfamily Cyclophoroidea), and covers the genera Alycaeus and Pincerna. Three new species are described: Alycaeus goliath Páll-Gergely, n. sp. (central Laos), Pincerna acroptychia n. sp. (Ha Giang Province, northern Vietnam), Pincerna viginticostatus n. sp. (Lang SÆ¡n Province, northern Vietnam). Pincerna vallis Z.-Y. Chen & M. Wu, 2020 is treated as a junior synonym of Pincerna costulosus (Bavay & Dautzenberg, 1912), and Pincerna clausus D. S. Do & T. S. Nguyen, 2022 as a synonym of Pincerna vanbuensis (Bavay & Dautzenberg, 1900).

The genus Acicula W. Hartmann, 1821 in the Caucasus (Gastropoda: Caenogastropoda: Aciculidae).

The Aciculidae is a family of terrestrial operculate snails with a western Palaearctic distribution. Historically three Acicula species were reported from the Caucasus Mountains, which represents the eastern edge of the family's distribution: A. limbata, A. moussoni and A. parcelineata, all from a few localities. We examined extensive material from the entire range of the Caucasus Mountains by means of classic morphology-based taxonomy and geometric morphometries. We arrived at the following conclusions: (1) At least three species inhabit the Caucasus Mountains, two of which are problematic taxonomically and regarding their nomenclature. (2) The two syntypes of A. moussoni have been lost, and both lectotype designations by the former authors were invalid. Therefore, we designate a neotype for A. moussoni. (3) Acicula limbata was described from Lower Miocene deposits of the Czech Republic. Although the fossil Central European and extant Caucasian shells differ only slightly from one another, it is highly unlikely that they would belong to the same species. Therefore, we suggest using A. limbata only for the Czech fossil species and A. moussoni for the Caucasian extant species. (4) In multiple samples, the generally smaller Acicula parcelineata was found syntopic with the generally larger A. moussoni. Therefore, the two are possibly distinct species. However, it is very difficult to distinguish, and the problem of A. moussoni and A. parcelineata needs further attention. (5) A species with a bullet (or torpedo)-shaped shell and an opisthocline apertural profile from the northern Caucasus region has been treated as A. moussoni by previous authors, but it is distinct from the other two Acicula species by consistent conchological characters and was also found with them in syntopy, and is described here as Acicula telum Páll-Gergely, n. sp.

Adapting mark-recapture methods to estimating accepted species-level diversity: a case study with terrestrial Gastropoda.

We introduce a new method of estimating accepted species diversity by adapting mark-recapture methods to comparisons of taxonomic databases. A taxonomic database should become more complete over time, so the error bar on an estimate of its completeness and the known diversity of the taxon it treats will decrease. Independent databases can be correlated, so we use the time course of estimates comparing them to understand the effect of correlation. If a later estimate is significantly larger than an earlier one, the databases are positively correlated, if it is significantly smaller, they are negatively correlated, and if the estimate remains roughly constant, then the correlations have averaged out. We tested this method by estimating how complete MolluscaBase is for accepted names of terrestrial gastropods. Using random samples of names from an independent database, we determined whether each name led to a name accepted in MolluscaBase. A sample tested in August 2020 found that 16.7% of tested names were missing; one in July 2021 found 5.3% missing. MolluscaBase grew by almost 3,000 accepted species during this period, reaching 27,050 species. The estimates ranged from 28,409 ± 365 in 2021 to 29,063 ± 771 in 2020. All estimates had overlapping 95% confidence intervals, indicating that correlations between the databases did not cause significant problems. Uncertainty beyond sampling error added 475 ± 430 species, so our estimate for accepted terrestrial gastropods species at the end of 2021 is 28,895 ± 630 species. This estimate is more than 4,000 species higher than previous ones. The estimate does not account for ongoing flux of species into and out of synonymy, new discoveries, or changing taxonomic methods and concepts. The species naming curve for terrestrial gastropods is still far from reaching an asymptote, and combined with the additional uncertainties, this means that predicting how many more species might ultimately be recognized is presently not feasible. Our methods can be applied to estimate the total number of names of Recent mollusks (as opposed to names currently accepted), the known diversity of fossil mollusks, and known diversity in other phyla.

A review of the genus Laeocathaica Möllendorff, 1899 (Gastropoda, Pulmonata, Camaenidae).

In this paper an overview of the Laeocathaica species is provided, and the intraspecific variability of several Laeocathaica species demonstrated on multiple shells. Laeocathaicahisanoi Páll-Gergely, sp. nov. and L.minwui Páll-Gergely, sp. nov. are described based on specimens found in museum collections. Five new synonyms are recognized: L.prionotropisalbocincta Möllendorff, 1899 is a new synonym of L.prionotropis Möllendorff, 1899, L.stenochone Möllendorff, 1899 is a new synonym of Laeocathaicacarinifera (H. Adams, 1870). Laeocathaicadistinguenda Möllendorff, 1899, L.tropidorhaphe Möllendorff, 1899, and L.dangchangensis Chen & Zhang, 2004 are moved to the synonymy of Laeocathaicaamdoana Möllendorff, 1899. Furthermore, photos of paratypes of Cathaicabizonalis Chen & Zhang, 2004 are published for the first time.

Revision of the " Chloritisdelibrata (Benson, 1836)" group (Gastropoda, Stylommatophora, Camaenidae).

Chloritisdelibrata (Benson, 1836), known from northeastern India, was believed to have three varietal forms, sometimes mentioned as subspecies: C.delibratavar.khasiensis (Nevill, 1877) and C.delibratavar.fasciata (Godwin-Austen, 1875) from the Khasi Hills, India, and C.delibratavar.procumbens (Gould, 1844) from Dawei in Myanmar. The reproductive anatomy of the latter form is known and does not match with those of any continental camaenid genera, but does with that of the newly examined Chloritisplatytropis Möllendorff, 1894 from Thailand. The latter species is conchologically similar to Bouchetcamaenahuberi Thach, 2018 (synonym of Helixfouresi Morlet, 1886), which is the type species of the genus Bouchetcamaena Thach, 2018. Thus, Bouchetcamaena can provisionally host the entire Chloritisdelibrata -group with the exception of var. fasciata, which is transferred to Burmochloritis Godwin-Austen, 1920 due to the multiple reddish bands on its shell. The examination of shells deposited in the Natural History Museum, London revealed that seven morphologically distinguishable forms are present, which are accepted here as representing distinct species. Four new species are described from India: Bouchetcamaenafoveata Páll-Gergely sp. nov., B.fusca Páll-Gergely sp. nov., B.raripila Páll-Gergely sp. nov., and B.subdelibrata Páll-Gergely sp. nov.

A Georgian and an Iranian new species of Renea G. Nevill, 1880 enormously extend the genus's distribution (Gastropoda: Caenogastropoda: Aciculidae).

Renea caucasica n. sp. and R. nemethi n. sp. are described from Georgia and northern Iran, respectively. Since the genus Renea has been reported from an area between south-eastern France and southern Albania, these two species extend the distribution of Renea eastwards enormously.

Nineteen new species of Alycaeidae from Myanmar and Thailand (Gastropoda: Caenogastropoda: Cyclophoroidea).

Nineteen new species of the alycaeid genera Chamalycaeus, Dicharax, and Metalycaeus are described from Thailand and Myanmar: Chamalycaeus buaboke Páll-Gergely A. Reischütz, n. sp., C. erawan Páll-Gergely Hunyadi, n. sp., C. hirpex Páll-Gergely A. Reischütz, n. sp., C. irmatallus Páll-Gergely, n. sp., C. krabiensis Páll-Gergely A. Reischütz, n. sp., C. serratus Páll-Gergely Auffenberg, n. sp., C. spiratus Páll-Gergely, n. sp., Dicharax (?) admirandus Páll-Gergely Auffenberg, n. sp., D. cyclostoma Páll-Gergely, n. sp., D. ebrius Páll-Gergely Auffenberg, n. sp., D. (?) gnomus Páll-Gergely, n. sp., D. mirounga Páll-Gergely, n. sp., D. ovatus Páll-Gergely Auffenberg, n. sp., D. subroseus Páll-Gergely, n. sp., D. verrucosus Páll-Gergely Hunyadi, n. sp., Metalycaeus anas Páll-Gergely A. Reischütz, n. sp., M. aries Páll-Gergely Auffenberg, n. sp., M. bicarinatus Páll-Gergely Hunyadi, n. sp., M. pygmachos Páll-Gergely Hunyadi, n. sp. Alycaeus kengtungensis Godwin-Austen, 1914 is moved to the synonymy of Metalycaeus heudei (Bavay Dautzenberg, 1900). We also report exact localities of Dicharax ataranensis (Godwin-Austen, 1914), Dicharax notus (Godwin-Austen, 1914), and Dicharax omissus (Godwin-Austen, 1914). The new records extend the known distribution of Chamalycaeus and Metalycaeus in Thailand.

Genus-level revision of the Alycaeidae (Gastropoda, Cyclophoroidea), with an annotated species catalogue.

412 species-group names (including 11 replacement names), and 14 genus-group names of the Alycaeidae have been introduced to date. Type materials of 85% (336) of the known species and subspecies were examined, a further 5% (19) of the taxa were studied using available non-type material, and for another 6% (22) the original descriptions were sufficiently detailed to evaluate their taxonomic status. Only 3% of the taxa (12) could not be examined. Special attention was paid to the sculpture of the embryonic whorls and the sutural tube-microtunnel system in order to provide a novel classification for this group. In this study 363 taxa (320 species or 43 subspecies) are accepted within the family Alycaeidae. Of these, 22 have been described by the lead author and his coauthors in previous publications. In addition, there are 18 species that were formerly classified in Cycloryx and now belong to Pincerna due to its synonymy with Cycloryx. Among the remaining 323 species, 209 (65%) are transferred here to another genus, whilst 114 (35%) have remained in their original genus. Seven genera are accepted. While some questions (e.g., the distinction between Pincerna and Alycaeus) remained unanswered, this revision made three main achievements: (1) The Dicharax species were identified based on the absence of spiral striation on the entire shell; (2) the Metalycaeus species were identified based on the spiral striation of the protoconch; (3) and Stomacosmethis was separated from Alycaeus based on the extremely short sutural tube. Five nominal species are being synonymised with other species, and eight species are now treated as subspecies. The following replacement names are proposed: Dioryx urnula niosiensis Páll-Gergely, nom. nov. for Alycaeus urnula var. daflaensis Godwin-Austen, 1914; Dioryx urnula rotundus Páll-Gergely, nom. nov. for Alycaeus urnula var. globosus Godwin-Austen, 1914; Pincerna crenilabris juttingae Páll-Gergely, nom. nov. for Alycaeus crenilabris laevis van Benthem Jutting, 1959; Pincerna crenilabris korintjiensis Páll-Gergely, nom. nov. for Alycaeus crenilabris latecostatus van Benthem Jutting, 1959; Dicharax conicus jatingaensis Páll-Gergely, nom. nov. for Alycaeus conicus var. nanus Godwin-Austen, 1914; Metalycaeus godwinausteni Páll-Gergely, nom. nov. for Alycaeus neglectus Godwin-Austen, 1914; and finally Metalycaeus suhajdai Páll-Gergely, nom. nov. for Alycaeus varius Godwin-Austen, 1914.

Hybridization and recurrent evolution of left-right reversal in the land snail genus Schileykula (Orculidae, Pulmonata).

The land snail genus Schileykula Gittenberger, 1983 is distributed in arid limestone areas from western Turkey to north-western Iran. It comprises eight species, which display high variation in shell size and morphology. The cylindrical shells are 5-12 mm in height and the last shell whorls bear several inner lamellae and plicae. Two taxa differ in their chirality having sinistral shells, while all the others are dextrals such as the vast majority of orculids. The aim of this study was to establish a molecular genetic phylogeny of Schileykula and to test whether it conforms to the current morphology-based classification. Furthermore, we were interested in the phylogenetic position of the two sinistral forms in order to assess whether one or two reversals happened in the evolution of the genus. Nine out of ten species, including all four subspecies of Schileykula trapezensis and three of six subspecies of Schileykula scyphus, were investigated. A section of the mitochondrial cytochrome c oxidase subunit I gene was analyzed in 54 specimens of Schileykula and from a subsample, partial sequences of the mitochondrial genes for the 12S rRNA and the 16S rRNA, and a section of the nuclear H4/H3 histone gene cluster were obtained. The phylogenetic trees based on the mitochondrial sequences feature high support values for most nodes, and the species appear well differentiated from each other. The two chiral forms evolved independently and are not sister lineages. However, some groupings disagree with the present morphology-based classification and taxonomical conclusions are drawn. Schileykula trapezensis is polyphyletic in the molecular genetic trees; therefore, three of its subspecies are elevated to species level: Schileykula acampsis Hausdorf, 1996 comb. nov., Schileykula neuberti Hausdorf, 1996 comb. nov., and Schileykula contraria Neubert, 1993 comb. nov. Furthermore, Schileykula sigma is grouped within S. scyphus in the mitochondrial and nuclear trees and consequently treated as a subspecies of the latter (Schileykula scyphus sigma Hausdorf, 1996 comb. nov.). Schileykula nordsiecki, whose shell morphology is indistinguishable from that of the neighboring Schileykula scyphus lycaonica, but who differs in its genital anatomy, was confirmed to represent a distinct lineage. The phylogenies produced by the mitochondrial and nuclear data sets are to some extent conflicting. The patterns differ concerning the grouping of some specimens, suggesting at least two independent hybridization events involving S. contraria, S. scyphus and S. trapezensis. The results exemplify the importance of integrating both mitochondrial and nuclear sequence data in order to complement morphology-based taxonomy, and they provide further evidence for hybridization across distantly related lineages in land snails.

The value of a single character: the Paleogene European land snail Ferussina Grateloup, 1827 is likely a cyclophorid (Gastropoda, Caenogastropoda).

Ferussina Grateloup, 1827 is a European Paleogene land snail genus, which is currently classified in its own family, the Ferussinidae Wenz, 1923 (1915), in the superfamily Cyclophoroidea. The shell of this genus is remarkable by its last quarter whorl turning towards the apex instead of away from it, which is an unusual trait in terrestrial snails. We show, however, that this trait has evolved at least nine times in terrestrial Eupulmonata and Caenogastropoda, and it does not justify distinction at the family level in any of the reported cases. This observation suggests the systematic position of Ferussina should not be based on the apexward-turning last quarter whorl alone but instead on the general morphology of the shell. As a result, we re-evaluate the systematic position of the Ferussinidae and treat it as a subfamily of the Cyclophoridae.

Molecular phylogeny and trait evolution of Madeiran land snails: radiation of the Geomitrini (Stylommatophora: Helicoidea: Geomitridae).

The Geomitrini is the most species-rich group of land snails in the Madeiran Archipelago. The phylogeny of the group is reconstructed based on mitochondrial and nuclear genetic markers. The timing of diversification, the colonisation history of the islands of the Madeiran Archipelago and the evolution of characters of the dart apparatus are studied. The results of the phylogenetic analyses confirm the sister group relationship of Geomitrini and Cochlicellini, but also show that several previously accepted genus-group taxa are not monophyletic. A new classification for the Geomitrini is proposed, including the description of two new genera, Domunculifex Brozzo, De Mattia, Harl & Neiber, n. gen. and Testudodiscula Brozzo, De Mattia, Harl & Neiber, n. gen. The onset of diversification of Geomitrini was dated in our analysis at 13 Ma, which largely coincides with the emergence of the present-day islands. The ancestral state estimation recovered the presence of two appendiculae in the reproductive system as the ancestral state in Geomitrini. One appendicula was lost three times independently within the tribe and is even missing completely in one group. The ancestral area estimation suggests recurrent colonisations of Madeira (and the Ilhas Desertas) from the older island Porto Santo.

New insights in Trichochloritis Pilsbry, 1891 and its relatives (Gastropoda, Pulmonata, Camaenidae).

The genus Bellatrachia Schileyko, 2018 was described based on a specimen identified as Helix (Chloritis) pseudomiara Bavay & Dautzenberg, 1909. We concluded that the examined specimen is not that species, but Helixcondoriana Crosse & Fischer, 1863. Therefore, (1) the type species of Bellatrachia must be replaced with Helixcondoriana; (2) the species Helix (Chloritis) pseudomiara must be re-allocated to the genus Trichochloritis; (3) the erroneous treatment of the genus Trichochloritis by Schileyko (2007) needs to be corrected through the description of a new genus, Dentichloritis gen. nov. based on Helixbrevidens Sowerby I, 1841. In addition, Chloritismicrotricha Möllendorff, 1898 is treated as a synonym of Helixcondoriana, and further information on the genitalia of Chloritis (?) bifoveata (Benson, 1856) is presented.

Taxi drivers: the role of animals in transporting mycorrhizal fungi.

Dispersal of mycorrhizal fungi via animals and the importance for the interacting partners' life history as well as for ecosystems is an understudied topic. In this review, we describe the available evidence and the most important knowledge gaps and finally suggest ways to gain the missing information. So far, 33 articles have been published proving a successful transfer of mycorrhizal propagules by animals. The vast majority of research on invertebrates was focused on arbuscular mycorrhizal (AM) fungi, whereas papers on vertebrates (mainly rodents and artiodactyls) equally addressed ectomycorrhizal (ECM) and AM fungi. Effective dispersal has been mostly shown by the successful inoculation of bait plants and less commonly by spore staining or germination tests. Based on the available data and general knowledge on animal lifestyles, collembolans and oribatid mites may be important in transporting ECM fungal propagules by ectozoochory, whereas earthworms, isopods, and millipedes could mainly transfer AM fungal spores in their gut systems. ECM fungal distribution may be affected by mycophagous dipterans and their hymenopteran parasitoids, while slugs, snails, and beetles could transport both mycorrhizal groups. Vertebrates feeding on fruit bodies were shown to disperse mainly ECM fungi, while AM fungi are transported mostly accidentally by herbivores. The important knowledge gaps include insufficient information on dispersal of fungal propagules other than spores, the role of invertebrates in the dispersal of mycorrhizal fungi, the way in which propagules pass through food webs, and the spatial distances reached by different dispersal mechanisms both horizontally and vertically.

A review of Aulacospira Möllendorff, 1890 and Pseudostreptaxis Möllendorff, 1890 in the Philippines (Gastropoda, Pupilloidea, Hypselostomatidae).

The genera Aulacospira and Pseudostreptaxis of the Philippines are revised based on the collections of the Senckenberg Forschungsinstitut und Naturmuseum (Frankfurt am Main, Germany), the Florida Museum of Natural History (USA), and recently collected material. Three new species are described: Aulacospiralens Páll-Gergely & Auffenberg, sp. n., Aulacospirakrobyloides Páll-Gergely & Schilthuizen, sp. n., Pseudostreptaxisharli Páll-Gergely & Schilthuizen, sp. n.

Revision of the subterranean genus Spelaeodiscus Brusina, 1886 (Gastropoda, Pulmonata, Spelaeodiscidae).

The Balkan genus Spelaeodiscus Brusina, 1886 is revised based on museum collections and newly collected samples from Montenegro and Albania. The following species and subspecies are introduced as new to science: Spelaeodiscus albanicus edentatus Páll-Gergely & P. L. Reischütz, ssp. n. (southern Montenegro and northern Albania), Spelaeodiscus densecostatus Páll-Gergely & A. Reischütz, sp. n., Spelaeodiscus hunyadii Páll-Gergely & Deli, sp. n., Spelaeodiscus latecostatus Páll-Gergely & Eross, sp. n. (all three from southern Montenegro), Spelaeodiscus unidentatus acutus Páll-Gergely & Fehér, ssp. n., and Spelaeodiscus virpazarioides Páll-Gergely & Fehér, sp. n. (both from northern Albania). For all species and subspecies diagnoses and suggestions for conservation status assessments according to IUCN criteria are provided. An overview is given regarding the habitat preference of Spelaeodiscus species, and the "scratch and flotate" method to collect subterranean gastropods.

Range-constrained co-occurrence simulation reveals little niche partitioning among rock-dwelling Montenegrina land snails (Gastropoda: Clausiliidae).

AIM: Taxon co-occurrence analysis is commonly used in ecology, but it has not been applied to range-wide distribution data of partly allopatric taxa because existing methods cannot differentiate between distribution-related effects and taxon interactions. Our first aim was to develop a taxon co-occurrence analysis method that is also capable of taking into account the effect of species ranges and can handle faunistic records from museum databases or biodiversity inventories. Our second aim was to test the independence of taxon co-occurrences of rock-dwelling gastropods at different taxonomic levels, with a special focus on the Clausiliidae subfamily Alopiinae, and in particular the genus Montenegrina. LOCATION: Balkan Peninsula in south-eastern Europe (46N-36N, 13.5E-28E). METHODS: We introduced a taxon-specific metric that characterizes the occurrence probability at a given location. This probability was calculated as a distance-weighted mean of the taxon's presence and absence records at all sites. We applied corrections to account for the biases introduced by varying sampling intensity in our dataset. Then we used probabilistic null-models to simulate taxon distributions under the null hypothesis of no taxon interactions and calculated pairwise and cumulated co-occurrences. Independence of taxon occurrences was tested by comparing observed co-occurrences to simulated values. RESULTS: We observed significantly fewer co-occurrences among species and intra-generic lineages of Montenegrina than expected under the assumption of no taxon interaction. MAIN CONCLUSIONS: Fewer than expected co-occurrences among species and intrageneric clades indicate that species divergence preceded niche partitioning. This suggests a primary role of non-adaptive processes in the speciation of rock-dwelling gastropods. The method can account for the effects of distributional constraints in range-wide datasets, making it suitable for testing ecological, biogeographical, or evolutionary hypotheses where interactions of partly allopatric taxa are in question.

Enantiomorphs and taxonomy of three conchological species in flat-shelled snails Trichocathaica (Pulmonata, Camaenidae).

Biomodal (flat/globular or slender/tall) shell/body shapes are associated with dichotomous (simultaneous reciprocal or non-reciprocal) modes of copulation behaviour in the fully-shelled stylommatophoran snails. In flat-shelled groups that copulate simultaneously reciprocally, no study has found an example of enantiomorphism that persists within a population. However, the original description of a flat camaenid snail, Trichocathaicaamphidroma, noted that it is dextral- or sinistral-coiled. By examination of shell surface morphology, we found that shell specimens classified as those of this species include shells of three different morphological species. Namely, T.amphidroma, Trichocathaicavestita (Pilsbry, 1934), comb. n., and Trichocathaicamacrosquamata Páll-Gergely, sp. n. In each of the three species, both sinistral and dextral shells have been collected from presumably one area. Ethanol-fixed soft bodies of single dextral and sinistral individuals of T.vestita, which were available for the first time for interchiral comparison of genital morphology in the present genus, differed from each other in the pattern of penial microsculpture. They might represent enantiomorphs that have recently diverged in allopatry instead of enantiomorphism within a population or species. However, their shell and genital differences were not discrete enough to divide them taxonomically into two morphologically distinct species. Our results demonstrate the importance of evaluating individual variation relative to differences between incipient species in penial morphology, especially between conchologically indistinguishable enantiomorphs in the flat groups. We revise the taxonomy of the genus Trichocathaica including the above-mentioned new species, and Trichocathaicaputeolata Páll-Gergely, sp. n.