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A new tateid genus, Ngalidrobia n. gen., containing six new species, is described from groundwater sampled from wells in the Ngalia Basin in the Northern Territory, Australia. The new species differ in their shell morphology which ranges from near planispiral to conical. Of these species, two live in sympatry in one location, the remainder being allopatric. Of the named tateid genera, Ngalidrobia is, on the basis of molecular results using three partial sequences (cytochrome c oxidase subunit I, and 16S and 28S ribosomal RNA), most closely related to Trochidrobia from artesian springs in northern South Australia.

The limacoid land snail Asperitas Gude, 1911 encompasses several vividly coloured, yet poorly known species that are distributed throughout the Lesser Sunda Islands, Sulawesi, and the Moluccas. We examined the variation in shell morphology, including the use of geometric morphometrics, and reproductive anatomy of snails from Timor and several adjacent islands. These studies revealed that none of the taxa described from Timor and considered to be endemic to this island could be reliably distinguished from any of the others. In addition to the systematic ambiguity of morphological characteristics, we uncovered rather low amounts of genetic differentiation in the mitochondrial marker cytochrome c oxidase subunit I that was not consistent with the current taxonomy. Based on these observations, we conclude that there is just a single Asperitas species on Timor that exhibits notable variability in shell characters and body colour. This variability is ascribed to the combined effects of polymorphic colour patterns with locally varying selection in different habitats and along altitudinal gradients. Individuals from the adjacent islands of Flores, Sumbawa, Solor and Romang, which are deemed to represent distinct species‐level taxa, exhibit similar amounts of variation in shell and body colour. They exhibit a consistent reproductive anatomy and overall negligible amounts of mitochondrial differentiation from the populations on Timor. Patterns in shell variation do not lend support to previously held ideas that different Sunda Islands harbour distinct radiations of polytypic Asperitas species. By contrast, we suggest that the taxonomic diversity of Asperitas has been overestimated for the over‐reliance on shell features and that many presently accepted taxa are likely mere synonyms of fewer and more widespread species.

International audience; This study presents the first record of the previously monotypic family Bouchetispiridae (Neogastropoda: Conoidea) outside of New Caledonia and provides the taxonomic description of Bouchetispira ponderi n. sp. from deep waters off the coast of New South Wales, Australia. Molecular analysis based on cytochrome c oxidase subunit I (COI), 16S ribosomal RNA (16S rRNA) and 12S ribosomal RNA (12S rRNA) mitochondrial markers confirms its placement within the family, which is corroborated based on similarities of the shell and hypodermic radula to its sister taxon Bouchetispira vitrea. B. ponderi differs from the latter in having shouldered, distinctly less convex whorls and a thicker, more opaque shell, as well as in details of the radula. Furthermore, the molecular results presented herein support its recognition as a new species. B. ponderi bears notable similarities in several shell characters to Belomitra pacifica (Belomitridae), providing another example of convergence with regards to shell morphology in the Neogastropoda.

Although raphitomid snails are a dominant component of gastropod communities in deep seas worldwide, their systematics is still largely tentative. We assembled the most complete sampling of Raphitomidae from south-eastern Australia to date. Based on morphological and molecular data from this material, we produced a robust phylogenetic framework and used it to delimit genera. For the focus area, our results show a large proportion of undescribed species- and genus-level taxa, 11 of which are formally described herein. We demonstrate that the examination of purely morphological characters rarely suffices for the purpose of accurate genus delimitation. As a result, some traditionally highly diverse raphitomid genera (such as Gymnobela) turn out to be artificial assemblages of several unrelated, mostly undescribed, genus-level lineages. Our data suggest that comparable configurations of shell and radular features, observed at the genus level, commonly do not reflect true phylogenetic relationships. However, our results are inconclusive as to whether homoplasy or conservatism are the drivers of this phenomenon. Accommodating for the inevitable sampling biases, south-eastern Australia appears as a possible hotspot for both raphitomid diversity and endemism, when compared with adjacent areas.

International audience; The deep-sea malacofauna of temperate Australia remains comparatively poorly known. However, a recent influx of DNA-suitable material obtained from a series of deep-sea cruises has facilitated integrative taxonomic study on the Conoidea (Caenogastropoda : Neogastropoda). Building on a recent molecular phylogeny of the conoidean family Raphitomidae, this study focussed on the genera Gladiobela and Pagodibela (both Criscione, Hallan, Puillandre & Fedosov, 2020). We subjected a representative mtDNA cox1 dataset of deep-sea raphitomids to ABGD, which recognised 14 primary species hypotheses (PSHs), 9 of which were converted to secondary species hypotheses (SSHs). Following the additional examination of the shell and hypodermic radula features, as well as consideration of bathymetric and geographic data, seven of these SSHs were recognised as new to science and given full species rank. Subsequently, systematic descriptions are provided herein. Of these, five are attributed to Gladiobela (three of which are endemic to Australia and two more widely distributed) and two are placed in Pagodibela (one endemic to southern Australia and one widespread in the Pacific). The rarity of many 'turrids' reported in previous studies is confirmed herein, as particularly indicated by highly disjunct geographic records for two taxa. Additionally, several of the studied taxa exhibit wide Indo-Pacific distributions, suggesting that wide geographic ranges in deep-sea 'turrids' may be more common than previously assumed. Finally, impediments to deep-sea 'turrid' taxonomy in light of such comparative rarity and unexpectedly wide distributions are discussed.

The deep sea of temperate south-eastern Australia appears to be a ‘hotspot’ for diversity and endemism of conoidean neogastropods of the family Raphitomidae. Following a series of expeditions in the region, a considerable amount of relevant DNA-suitable material has become available. A molecular phylogeny based on this material has facilitated the identification of diagnostic morphological characters, allowing the circumscription of monophyletic genera and the introduction of several new genus-level taxa. Both named and new genera are presently being investigated through integrative taxonomy, with the discovery of a significant number of undescribed species. As part of this ongoing investigation, our study focuses on the genera Famelica Bouchet & Warén, 1980, Glaciotomella Criscione, Hallan, Fedosov & Puillandre, 2020 and Rimosodaphnella Cossmann, 1914. We subjected a comprehensive mitochondrial DNA dataset of representative deep-sea raphitomids to the species delimitation methods ABGD and ASAP that recognised 18 and 15 primary species hypotheses (PSHs) respectively. Following additional evaluation of shell and radular features, and examination of geographic and bathymetric ranges, nine of these PSHs were converted to secondary species hypotheses (SSHs). Four SSHs (two in Famelica and two in Rimosodaphnella) were recognised as new, and formal descriptions are provided herein.

Background Our knowledge of the benthic fauna at lower bathyal to abyssal (LBA, > 2000 m) depths off Eastern Australia was very limited with only a few samples having been collected from these habitats over the last 150 years. In May–June 2017, the IN2017_V03 expedition of the RV Investigator sampled LBA benthic communities along the lower slope and abyss of Australia’s eastern margin from off mid-Tasmania (42°S) to the Coral Sea (23°S), with particular emphasis on describing and analysing patterns of biodiversity that occur within a newly declared network of offshore marine parks. Methods The study design was to deploy a 4 m (metal) beam trawl and Brenke sled to collect samples on soft sediment substrata at the target seafloor depths of 2500 and 4000 m at every 1.5 degrees of latitude along the western boundary of the Tasman Sea from 42° to 23°S, traversing seven Australian Marine Parks. Results The biological sampling included 35 beam trawls, 28 Brenke sleds, 8 box cores, 20 surface meso-zooplankton tows, and 7 Deep Towed Camera transects. In total, 25,710 specimens were identified to 1084 taxonomic entities, including 847 species-level, 144 genus-level and 69 family-level and 24 higher-level taxa. Of the species-level taxa, only 457 were assigned species-level taxonomic names, which implies that up to 58% of the collected fauna is undescribed. In addition, the ranges of numerous species have been extended to include the western Tasman Sea. Conclusions The lower bathyal and abyssal fauna of soft sediment seafloors off eastern Australia has been systematically surveyed for the first time. The resultant collections will provide the foundation for much future ecological, biogeographical, phylogenetic and taxonomic research.

In the latest systematic revision of the camaenid land snail Kimberleytrachia from the Western Australian Kimberley region by Criscione and Kohler (2014), two species were confused. This error is corrected herein: The species described as K. leopardus Criscione & Kohler, 2014 is in fact identical with the earlier described species K. umbonis (Solem, 1979). Therefore, the name K. leopardus is a junior synonym of the latter. By contrast, material assigned to K. umbonis by Criscione and Kohler (2014) represented a yet unnamed species, which is here newly described as K. bachstenensis n. sp. Both species occur in the Prince Regent River National Park: K. umbonis occurs north of the Prince Regent River while K. bachstenensis n. sp. occurs south of it. http://www.zoobank.org/urn:lsid:zoobank.org:act:459E83CD-6C10-46AE-A73B-DDC5EB9F350A

The practice of species delimitation using molecular data commonly leads to the revealing of species complexes and an increase in the number of delimited species. In a few instances, however, DNA-based taxonomy has led to lumping together of previously described species. Here, we delimit species in the genus Cryptogemma (Gastropoda: Conoidea: Turridae), a group of deep-sea snails with a wide geographical distribution, primarily by using the mitochondrial COI gene. Three approaches of species delimitation (ABGD, mPTP and GMYC) were applied to define species partitions. All approaches resulted in eight species. According to previous taxonomic studies and shell morphology, 23 available names potentially apply to the eight Cryptogemma species that were recognized herein. Shell morphometrics, radular characters and geographical and bathymetric distributions were used to link type specimens to these delimited species. In all, 23 of these available names are here attributed to seven species, resulting in 16 synonymizations, and one species is described as new: Cryptogemma powelli sp. nov. We discuss the possible reasons underlying the apparent overdescription of species within Cryptogemma, which is shown here to constitute a rare case of DNA-based species lumping in the hyper-diversified superfamily Conoidea.

The systematic classification of the Enidae of Timor is reviewed by means of comparative morphology and molecular phylogenetics using recently collected land snail samples from Timor-Leste (‘East Timor’). Features of the renal and genital anatomy as well as analyses of nuclear 28S rRNA sequences confirm the placement of the species in the Enidae. Generic combinations employed by earlier authors are discussed. The name Coccoderma Mollendorff, 1901 used for enids from the Indo-Australian Archipelago is pre-occupied by Coccoderma Zittel, 1887 and therefore not available. The assignment of species from Timor to Pseudonapaeus Westerlund, 1887, which is otherwise known from central Asia, is also rejected. Instead, the Enidae from Timor are here affiliated with Apoecus Kobelt, 1902, a name originally introduced for the Papuan species Buliminus colonus Mollendorff, 1895. While Apoecus samples from Timor-Leste form three distinct mitochondrial clades, only two groups can be reliably distinguished by their ...

A new species of Setobaudinia Iredale, 1933 (family Camaenidae Pilsbry, 1895) from the Kimberley region in Western Australia is described. Setobaudinia nicolasi n. sp. is endemic to Baudin Island, off the northwestern coast of Australia, where it occurs in sympatry with at least another three confamilial land snails. The new species is distinguished from other Setobaudinia species by a unique combination of features of its shell (low elevation and weak lip expansion) and male genitalia (inner penial wall sculpture of interlocking filaments).http://zoobank.org/urn:lsid:zoobank.org:pub:10FAB5A9-503A-4E3B-A67C-772D85658C91

Background The Great Australian Bight (GAB) comprises the majority of Australia’s southern coastline, but to date its deep water fauna has remained almost unknown. Recent issuing of oil and gas leases in the region has highlighted this lack of baseline biological data and established a pressing need to characterise benthic abyssal fauna. Methods From 2013 to 2017, six large-scale systematic surveys of the GAB were conducted from 200 to 5000 m depth, constituting the deepest systematic biological sampling in Australia. Sampling was conducted on soft sediment and hard substrates, both at pre-determined depth intervals along north-south transect lines and at sites of interest identified by multibeam sonar. Results A total of 66,721 invertebrate specimens were collected, comprising 1267 species, with 401 species (32%) new to science. In addition to the novelty of the fauna, there was a high degree of rarity, with 31% of species known only from single specimens. Conclusions In this paper, we provide an annotated checklist of the benthic invertebrate fauna of the deep GAB, supplemented with colour photos of live specimens and commentary on taxonomy, diversity and distributions. This work represents an important addition to knowledge of Australia’s deep sea fauna, and will provide the foundation for further ecological, biogeographical and systematic research.

Progressive aridification since the mid-Miocene has had a significant influence on the evolution of the biota in the arid zone of central Australia. Especially moisture sensitive groups, such as snails, are often restricted to topographically complex areas, which have acted as refugia in an otherwise inhospitable environment. This historical fragmentation is deemed to be a potent agent of allopatric lineage diversification. Camaenid land snails are amongst only a few terrestrial gastropods that have managed to survive in the arid zone probably due to their ability to escape desiccation through aestivation. Here, we present the first study of the mitochondrial lineage differentiation in an endemic land snail genus from the Australian 'Red Centre', Granulomelon Iredale, 1933. Exposing significant incongruence between mtDNA phylogeny and morphology-based taxonomy, we completely revise the species and genus level taxonomy of this camaenid group. We demonstrate that this genus contains three species, G. grandituberculatum, G. adcockianum and G. squamulosum, which have so far been assigned to different genera: Granulomelon Iredale, 1933 (junior synonym: Baccalena Iredale, 1937), Basedowena Iredale, 1937 and Pleuroxia Ancey, 1887. Two of these species are widespread comprising multiple divergent mitochondrial lineages. Based on a molecular clock estimate, these lineages diverged approximately during the mid-Pleistocene, a period of particularly severe aridification. The phylogeographic patterns are consistent with an isolation-by-distance model in one species but not the other. We suggest that these differences can be attributed to their distinctive aestivation behavior.

The camaenid genus Damochlora Iredale, 1938 endemic to the Western Australian Kimberley is poorly defined by shell characters only. Two out of three previously recognised species have recently been removed from this genus and placed in Setobaudinia Iredale, 1933 rendering the type species D. millepunctata (Smith, 1894) the only member of this genus. Based on the study of ethanol-preserved material from the type locality, Baudin Island, we revise the taxonomy of Damochlora, which is maintained as a distinct and monotypic genus. The examination of material from Cassini Island previously considered to be conspecific with D. millepunctata on account of possessing a nearly identical shell revealed that these snails represent a distinct species, for which the taxon name cassiniensis Smith, 1894 is available. This species is characterised by a profoundly different reproductive anatomy and therefore recognised as a distinct genus, for which the new name Nannochlora is being introduced.http://zoobank.org/urn:lsid:...

North-western Australia harbours more than 300 species of camaenid land snail in 41 genera exhibiting considerable and well documented morphological diversity. We performed Bayesian and Maximum Likelihood analyses of concatenated nuclear (28S) and mitochondrial (COI, 16S) DNA sequences from 140 species of 37 of these genera plus an additional 27 extralimital species in order to resolve their phylogenetic relationships and to address the significance of morphological characters for the delineation of monophyletic taxa. While north-western Australian Camaenidae in their entirety are not monophyletic with respect to extralimital groups, they underwent extensive in situ-diversification in several independent phylogenetic radiations. A Maximum Likelihood-based character history reconstruction revealed extensive convergence in all studied shell characters and in three out of four genital features across this group. However, in some genera close morphological similarity is best explained by the retention of ancestral characters. We hypothesize that both morphological stasis in some groups and convergent character evolution in others can to a large extent be attributed to adaptive transformations in response to historically increasing aridity throughout north-western Australia in concert with structural constraints.

Two new monotypic camaenid genera Cardiotrachia gen. nov. and Rachita gen. nov. are described for the two new species C. bastionensis n. sp. from the Bastion Ranges and R. carltonensis n. sp. from the Onslow Hills, respectively, in the East Kimberley, Western Australia. Cardiotrachia is characterized by distinct anatomical features, such as a small shell devoid of macroscopic sculpture with a peculiarly heart-shaped aperture and a coiled penis without epiphallus. Rachita is characterized by a shell flatter than that of any other camaenids of similar size from the East Kimberley, a lacking epiphallus and a complex penial wall sculpture. A mitochondrial DNA phylogeny corroborates the recognition of Cardiotrachia and Rachita as distinct genera with respect to other confamilial taxa from north-western Australia.http://zoobank.org/urn:lsid:zoobank.org:pub:60FA3A41-6A3B-4EBE-8B05-B7960B7EEEBF

Continuing the revision of the Camaenidae in the Australian Monsoon Tropics, we employed comparative analyses of morphological features (with a focus on shell and penial anatomy) and genetic markers (with a focus on mitochondrial COI and 16S sequences) to address the systematic relationships of land snails from the Victoria River District, Northern Territory, and adjacent East Kimberley (Western Australia). These analyses revealed that the species under study represented the previously undescribed genus Nanotrachia. This genus differs from all other camaenid genera known from north-western Australia most conspicuously by its small, flat, and ribbed shell. Six species are identified as members of the new genus, four of them new species (Nanotrachia costulata sp. nov., Nanotrachia carinata sp. nov., Nanotrachia coronata sp. nov., Nanotrachia levis sp. nov.). Two further species have already been described previously but assigned to different genera. These species, Ordtrachia intermedia (as the type species of Nanotrachia) and Mouldingia orientalis, are here transferred to Nanotrachia. Like other camaenids from the Australian Monsoon Tropics, species of Nanotrachia are characterized by essentially allopatric distributions, regional endemism, and a patchy distribution across their range.

The new, monotypic camaenid genus Arnhemtrachia is described for the new species Arnhemtrachia ramingining from Ramingining, Arnhem Land, Northern Territory, Australia with additional records from the Gove Peninsula in eastern Arnhem Land. This camaenid is characterised by a combination of distinct morphological features, such as a small, discoidal, keeled shell with regular axial ribs, open umbilicus and simple, rounded aperture as well as a reproductive system with a long epiphallus possessing a long flagellum and absence of a penial sheath, with a flap on the penial wall which transverses longitudinal pilasters, and a long, simple bursa copulatrix. Based on comparative morphology, Arnhemtrachia reveals affinities with Trozena morata Iredale, 1838 from NE Queensland.

We comprehensively revise the taxonomy of the camaenid genus Mesodontrachia Solem, 1985, which is endemic to the Victoria River District and East Kimberley in the north-western Australian Monsoon Tropics based on comparative analyses of key morphological features and mitochondrial DNA sequences. We examined newly collected samples from several collection sites spread over nearly 20 000 km2 of mostly inaccessible land, which represented all three currently known and three previously undescribed species. All species were initially identified as members of Mesodontrachia based on their similar, putatively typical shell. However, Mesodontrachia as so delimited was polyphyletic in a mitochondrial phylogeny with respect to several other camaenid genera from NW Australia. Contrary to the shell, we found considerable variation in the penial anatomy that was consistent with the mtDNA differentiation. To retain monophyletic taxa, we propose a revised taxonomy whereby Mesodontrachia is maintained as a monotypic taxon. In addition, four genera (Nodulabium, Ototrachia, Pseudomesodontrachia and Vincentrachia) and three species (P. gregoriana, O. compressa and N. solidum) are newly described. The shell of all these taxa is highly conserved and of little taxonomic utility. Shell similarity is attributed to a similar life style in a similar and harsh environment.

The Western Australian Kimberley region harbours a diverse fauna of camaenid land snails characterised by marked patterns of narrow range endemism. The recently described genus Australocosmica comprised three species that are endemic to single offshore islands or island groups. Material of a further seven candidate species recognised by the late Alan Solem has been examined. Six of these manuscript species, NSP 40 (= A. rotunda n. sp.), NSP 76 (= A. pallida n. sp.), NSP 77 (= A. buffonensis n. sp.), NSP 78 (= A. bernoulliensis n. sp.), NSP 79 (= A. crassicostata n. sp.), and NSP 80 (= A. nana n. sp.), are here newly described based on examination of shell morphology and penial anatomy. Based on our findings, we are presenting an updated generic diagnosis of Australocosmica. Statistical analyses revealed that species exhibit similar shell characters (colouration, sculpture, dimensions), which render the delimitation of species based only on shells difficult. However, species were found to differ significantly in their penial anatomy. Although the material studied was not suitable for DNA extraction, the anatomical differences were considered sufficient to permit the description of distinct species.

The Rissooidea is an evolutionarily ancient and mega-diverse group of marine micro-gastropods that occur from intertidal to deep waters at all latitudes. Their current systematics is predominantly based on phenetic grounds and there has been no comprehensive molecular phylogeny. Based on sequences of mitochondrial and nuclear DNA from the most complete sampling of Rissoidae to date, this work represents the first treatment of the group performed through a phylogenetic approach. The main goals are to clarify the phylogenetic position of the Rissoidae, investigate the relationships within rissoid taxa and test the utility of some diagnostic morphological traits. Our phylogeny indicates that the Rissoidae are one of six distinct family-lineages within the superfamily Rissooidea (along with Barleeiidae, Emblandidae, Lironobidae, Rissoinidae and Zebinidae) whose recognition is supported by several synapomorphies. While most of the characters studied exhibit widespread convergence, some others prove useful in separating genera and broader taxonomic groups. The relationships among rissoid taxa challenge the current systematics, indicating the non-monophyly of some genera with purportedly trans-oceanic distribution and the need of taxonomic revision for some highly diverse genera. Our phylogeny suggests that the Rissoidae originated in shallow seas and independently radiated into bathyal waters at least twice.

Vast parts of the monsoon tropics of Australia feature semi-arid habitats, which are generally thought to harbour a depauperate land snail fauna as compared to the mesic continental fringes, in particular the Australian wet tropics. However, our knowledge of land snails inhabiting these often remote environments is still very patchy. In order to improve the understanding of land snail diversity in the monsoon tropics, we revised the camaenid land snail genus Exiligada based on comprehensive collections, undertaken by use of helicopters on remote limestone outcrops in the Northern Territory and in Western Australia. Based on comparative analyses of shell and genital morphology and patterns of molecular differentiation, we recognize 15 species within Exiligada, 13 of which are newly described. In addition, we suggest a revised delimitation of the type species Exiligada negriensis, as compared to the latest available revision, by removing Exiligada qualis from its synonymy and recognizing it as a distinct species. A key for species identification is also provided. Molecular phylogenetic analyses strongly supported the monophyly of Exiligada with respect to other confamilial genera known to occur in the same geographical region. Most Exiligada species are narrowly endemic to restricted limestone outcrops that cover areas with a diameter of about 20 to 150 km. Within the distributional range of Exiligada, the ranges of up to seven species overlap but we never found more than three species to occur in sympatry at a given sampling site. We propose that species originated by allopatric differentiation, followed by secondary range expansion, leading to sympatric distributions. Our study confirms that less complex rock habitats in more xeric environments support no more than three sympatric species, this being likely to be a result of ecological exclusion. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166, 689–722.

The new, monotypic camaenid genus Setocallosa is described for the new species S. pathutchingsae from Arnhem Land, Top End of the Northern Territory. This camaenid is characterized by a combination of distinct morphological features, such as a small, weakly elevated shell with widely open umbilicus and thick callus on the parietal wall, a wide epiphallic flagellum, elongated penis and short bursa copulatrix with subglobose end. The relationships of Setocallosa with the other camaenid genera in the area are investigated by means of mtDNA, but its phylogenetic position remains ambiguous. S. pathutchingsae occurs in sympatry with Arnhemtrachia ramingining, but based on morphology the two camaenids can be readily differentiated.http://zoobank.org/urn:lsid:zoobank.org:pub:1C50CF24-7FEE-446A-9724-A0A4E850B5AA

The Rissooidea is one of the largest and most diverse molluscan superfamilies, with 23 recognized Recent families including marine, freshwater and terrestrial members. The Cingulopsoidea are a group of three marine families previously included within the Rissooidea. A previous molecular analysis including two rissooideans and one cingulopsoidean, indicated the possibility that the Rissooidea is at least diphyletic. We use new molecular data to investigate the polyphyly of Rissooidea and test the monophyly of Cingulopsoidea with a greatly increased taxon set. This study includes the greatest sampling to date with 43 species of 14 families of Rissooidea and all families of Cingulopsoidea. Bayesian and maximum likelihood analyses of 16S and 28S show that there are two major clades encompassing taxa previously included in Rissooidea. These are the Rissooidea s.s. containing Rissoidae and Barleeiidae and the Truncatelloidea containing Anabathridae, Assimineidae, Falsicingulidae, Truncatellidae, Pomatiopsidae, Hydrobiidae s.l., Hydrococcidae, Stenothyridae, Calopiidae, Clenchiellidae, Caecidae, Tornidae, and Iravadiidae. Rissoidae is not monophyletic, with Lironoba grouping with Emblanda (Emblandidae) and Rissoina forming a separate clade with Barleeiidae. Iravadiidae is not monophyletic, with Nozeba being sister to the Tornidae. Tatea, usually included within Hydrobiidae, is distinct from that family and Nodulus, previously included in Anabathridae, groups with the hydrobiids.

The land snail Basedowena Iredale, 1937 currently comprises eight species that inhabit mountain ranges in the central Australian arid zone. By studying the variation in shell and genital anatomy and the differentiation in the mitochondrial markers 16S and COI, we revise the taxonomy of this camaenid and describe new taxa. We demonstrate that the current morphology-based classification has been misled by homoplasy mainly in shell shape. In fact, Basedowena as herein revised contains species with vastly different shells, which have so far been assigned to different genera. By contrast, these species have the same general genital anatomy in common and form a clade in the mitochondrial phylogeny. Based on these findings, we transfer Pleuroxia bethana, P. hinsbyi, P. elfina, P. oligopleura, P. polypleura, P. radiata, Montanomelon angatjana and Minimelon colmani to Basedowena. While Pleuroxia and Montanomelon are maintained as distinct genera, although with fewer species, the monotypic Minimelon becomes a junior synonym of Basedowena. We identify and describe three new Basedowena species (B. bicolor, sp. nov., B. holoserica, sp. nov., B. siparium, sp. nov.). A fourth new species differs substantially from all other arid zone camaenids and is hence placed in a new genus, Xeromelon, gen. nov. The revised delineation of Basedowena renders it now the most widespread camaenid genus in Australia. It is distributed throughout the Australian arid zone from Western Australia, via the Northern Territory and South Australia into New South Wales.

Setobaudinia Iredale, 1933 is a genus of camaenid land snails endemic to the Western Australian Kimberley. It comprises 20 currently recognised species, most of which occur within the north-western high precipitation zone between the Admiralty Gulf and Collier Bay and within less than 60 km distance from the coast. Exceptionally, two species are found on isolated limestone outcrops in the drier interior of the Victoria River District, Northern Territory. By studying the differentiation in shell and genital anatomy as well as in the mitochondrial markers 16S and COI, we revise the taxonomy of Setobaudinia and describe new taxa. The Northern Territory species S. victoriana Solem, 1985 is identified as a member of the genus Trachiopsis, which otherwise comprises species from the York Peninsula, Queensland. The species Damochlora spina Solem, 1985 is shown to be a member of the genus Setobaudinia. A new species from the eastern Kimberley has been identified as the sister group of Setobaudinia. It is placed in the new genus Kymatobaudinia for exhibiting morphological characteristics that differ from those of all other Setobaudinia species. In addition, we describe nine new species from coastal areas and islands off the cost throughout the south-west to north-west Kimberley: S. angustilabiata, sp. nov.; S. colmani, sp. nov.; S. incisa, sp. nov.; S. kessneri, sp. nov.; S. latilabiata, sp. nov.; S. longiflagellata, sp. nov.; S. malbyana, sp. nov.; S. minima, sp. nov.; S. plana, sp. nov. ZooBank Publication code: http://zoobank.org/References/3C953F1A-62E5-4CE5-9D5E-D8D5774B4059

Baudinella Thiele, 1931, Retroterra Solem, 1985 and Molema Kohler, 2011 are three genera of camaenid land snail endemic to coastal regions of the Western Australian Kimberley. Each of these genera has fairly distinct shells, but all exhibit a rather similar configuration of the reproductive system, which is characterized by lack of a penial sheath and presence of an elongated and coiled bursa copulatrix. By combining comparative morphology of shell and penial anatomy with analyses of the mitochondrial DNA fragments 16S rRNA (16S) and cytochrome c oxidase subunit 1 (COI), the phylogenetic relationships amongst representative species of these genera are addressed to test the monophyly of taxa and to identify new species. Our results show that all three genera are members of a single camaenid radiation. Five new species are described: two new species of Baudinella, B. magna n. sp. from the Institute and Montesquieu Archipelagos and B. margaritata n. sp. from Pitta Gorge in the Prince Regent Reserve, one new species of Molema, Molema tenuicostata n. sp., from near Talbot Bay, and two new species of Retroterra, R. dichroma, and R. nana, from the Prince Regent Reserve.

Aim Camaenidae are amongst the most diverse land snail groups in Southeast Asia and Australasia, but their phylogeny and biogeography are poorly understood. The monophyly and biogeographical origin of the Australian species has remained uncertain. Being reported from north-western Australia as well as from the Lesser Sunda Islands, the genus Rhagada is crucial to our understanding of camaenid biogeography. By resolving the phylogeny of Rhagada, we aim to uncover spatial and temporal patterns of its diversification at the interface between Oriental and Australian biogeographical regions. Location North-western Australia, Lesser Sunda Islands. Methods We implemented Bayesian and maximum likelihood methods to generate the most complete mitochondrial phylogeny of Rhagada land snails to date. Divergence times of clades were estimated by employing a relaxed molecular clock and two internal calibrations from fossil and tectonic data. Ancestral areas of clades were inferred using character history reconstruction based on parsimony, as implemented in Mesquite. Results Rhagada clustered into eight well-supported clades that are restricted to certain geographical areas. Species from the Kimberley, Western Australia, formed the earliest branching clades. A single Lesser Sunda clade was sister to a radiation in the Western Australian Pilbara. Molecular age estimates placed the evolutionary origin of Rhagada between the late Miocene and early Pleistocene, and dispersal from Western Australia onto the Lesser Sunda Islands in a period between the mid-Pliocene and early Pleistocene. Main conclusions The camaenid Rhagada originated in the Kimberley and subsequently expanded its range through the Pilbara and into the Shark Bay area, probably during the late Pliocene and mid-Pleistocene. From the Kimberley, Rhagada snails colonized the Lesser Sunda Islands probably not before 1.9 Ma following emergence of the youngest islands, which may have acted as ‘stepping stones’. Over-sea dispersal might have occurred during the mid-Pleistocene when lowered sea levels facilitated faunal exchange across the region.