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Background: Snail-borne trematodes afflict humans, livestock, and wildlife. Recognizing their zoonotic potential and possible hybridization, a One Health approach is essential for effective control. Given the dearth of knowledge on African trematodes, this study aimed to map snail and trematode diversity, focusing on (i) characterizing gastropod snail species and their trematode parasites, (ii) determining infection rates of snail species as intermediate hosts for medically, veterinary, and ecologically significant trematodes, and (iii) comparing their diversity across endemic regions. Methods: A cross-sectional study conducted in 2021 in Chiredzi and Wedza districts in Zimbabwe, known for high human schistosomiasis prevalence, involved malacological surveys at 56 sites. Trematode infections in snails were detected through shedding experiments and multiplex rapid diagnostic polymerase chain reactions (RD-PCRs). Morphological and molecular analyses were employed to identify snail and trematode species. Results: Among 3209 collected snail specimens, 11 species were identified, including schistosome and fasciolid competent snail species. We report for the first time the invasive exotic snail Tarebia granifera in Zimbabwe, which was highly abundant, mainly in Chiredzi, occurring at 29 out of 35 sites. Shedding experiments on 1303 snails revealed a 2.24% infection rate, with 15 trematode species identified through molecular genotyping. Five species were exclusive to Chiredzi: Bolbophorus sp., Schistosoma mansoni, Schistosoma mattheei, Calicophoron sp., and Uvulifer sp. Eight were exclusive to Wedza, including Trichobilharzia sp., Stephanoprora amurensis, Spirorchid sp., and Echinostoma sp. as well as an unidentified species of the Plagiorchioidea superfamily. One species, Tylodelphys mashonensis, was common to both regions. The RD-PCR screening of 976 non-shedding snails indicated a 35.7% trematode infection rate, including the presence of schistosomes (1.1%) Fasciola nyanzae (0.6%). In Chiredzi, Radix natalensis had the highest trematode infection prevalence (33.3%), while in Wedza, R. natalensis (55.4%) and Bulinus tropicus (53.2%) had the highest infection prevalence. Conclusions: Our xenomonitoring approach unveiled 15 trematode species, including nine new records in Zimbabwe. Schistosoma mansoni persists in the study region despite six mass deworming rounds. The high snail and parasite diversity, including the presence of exotic snail species that can impact endemic species and biomedically important trematodes, underscores the need for increased monitoring. [ABSTRACT FROM AUTHOR]

Laetoli, Tanzania is one of the most important palaeontological and palaeoanthropological localities in Africa. We report on a survey of the extant terrestrial gastropod faunas of the Laetoli-Endulen area, examine their ecological associations and re-examine the utility of Pliocene fossil molluscs in palaeoenvironmental reconstruction. Standardised collecting at 15 sites yielded 7302 individuals representing 58 mollusc species. Significant dissimilarities were found among the faunas of three broad habitat types: forest, woodland/bushland and open (grassland and scattered, xeric shrubland). Overall, more species were recorded in the woodland/bushland sites than in the forest sites. Open sites were less diverse. Environmental factors contributing most strongly to the separation of habitat types were aridity index and elevation. The results are supplemented with new mollusc data from the Mbulu Plateau south of Lake Eyasi, and compared to the list of species cumulatively recorded from the Ngorongoro area. Some regional variation is apparent and historical factors may explain the absence of some fossil taxa from Laetoli today. Differences in seasonality separated upland forest sites on the Mbulu plateau from those at Lemagurut at Laetoli. Indicator species were identified for each habitat. These included several large-bodied species analogous to the Laetoli Pliocene fossil species that were then used for palaeoenvironmental reconstruction. Based on the estimated aridity index, and adopting the widely used United Nations Environment Programme (UNEP) global climate classification, the four stratigraphic subunits of the Upper Laetolil Beds (3.6–3.85 Ma) would be placed in either the UNEP's Dry Sub-humid or Semi-arid climate classes, whereas the Upper Ndolanya Beds (2.66 Ma) and Lower Laetolil Beds (3.85-<4.36 Ma) would be assigned to the Humid and Semi-arid climate classes respectively. Pliocene precipitation at Laetoli is estimated as 847–965 mm per year, refining previous estimates. This is close or slightly higher than the present mean annual precipitation, and is likely to have corresponded to a mosaic of forest, woodland and bushland within a grassland matrix consistent with other reconstructions. [ABSTRACT FROM AUTHOR]

Satellite DNA (sat-DNA) was previously described as junk and selfish DNA in the cellular economy, without a clear functional role. However, during the last two decades, evidence has been accumulated about the roles of sat-DNA in different cellular functions and its probable involvement in tumorigenesis and adaptation to environmental changes. In molluscs, studies on sat-DNAs have been performed mainly on bivalve species, especially those of economic interest. Conversely, in Gastropoda (which includes about 80% of the currently described molluscs species), studies on sat-DNA have been largely neglected. In this study, we isolated and characterized a sat-DNA, here named PcH-sat, in the limpet Patella caerulea using the restriction enzyme method, particularly HaeIII. Monomeric units of PcH-sat are 179 bp long, AT-rich (58.7%), and with an identity among monomers ranging from 91.6 to 99.8%. Southern blot showed that PcH-sat is conserved in P. depressa and P. ulyssiponensis, while a smeared signal of hybridization was present in the other three investigated limpets (P. ferruginea, P. rustica and P. vulgata). Dot blot showed that PcH-sat represents about 10% of the genome of P. caerulea, 5% of that of P. depressa, and 0.3% of that of P. ulyssiponensis. FISH showed that PcH-sat was mainly localized on pericentromeric regions of chromosome pairs 2 and 4–7 of P. caerulea (2n = 18). A database search showed that PcH-sat contains a large segment (of 118 bp) showing high identity with a homologous trait of the Nin-SINE transposable element (TE) of the patellogastropod Lottia gigantea, supporting the hypothesis that TEs are involved in the rising and tandemization processes of sat-DNAs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Wider distribution of invasive snails compared with native snails in the Limpopo River system. • cox 1 genetic data shows multiple lineages of invasive snails outside their native ranges. • More digenean species occurred in Pseudosuccinea columella than in the other snails. • The present xiphidiocercaria represents an unknown species of Orientocreadium. Invasive snails are associated with ecological problems in freshwater bodies worldwide. However, their impact on the transmission of digenean infections remain underreported. In the present study, 1708 specimens representing four snail species were sampled from four impoundments in the Limpopo River system in South Africa. Gyraulus chinensis (Planorbidae), Physella acuta (Physidae) and Pseudosuccinea columella (Lymnaeidae), which are invasive, were found in all the sampling sites. In contrast, the native lymnaeid Radix natalensis occurred at only one study site. Digeneans were observed only from R. natalensis (prevalence = 49%) and Ps. columella (prevalence = 23%). Morphological and genetic analyses revealed four digeneans: Fasciola nyanzae , Orientocreadium sp., Petasiger sp. and Patagifer vioscai. Pseudosuccinea columella was infected by the four digeneans while R. natalensis harboured only Orientocreadium sp. and Petasiger sp. Partial sequences of Orientocreadium sp. from the current study differed from congeners whose DNA data are available on GenBank, by p-distances of at least 1.84 and 2.2% for 28S and the internal transcribed spacer (ITS) rDNA, respectively. Phylogenetic analyses demonstrated that the present species is sister to Orientocreadium batrachoides. Genetic and phylogenetic data based on 28S and ITS rDNA suggested that Petasiger sp. from the present study and isolates of three unidentified Petasiger spp. from Kenya, Hungary and Australia, were representatives of the same species. This is the first known report of Orientocreadium , Petasiger and Patagifer from Ps. columella. The occurrence of F. nyanzae in Ps. columella indicates spillback from R. natalensis. These findings echo the concerns raised in previous studies about the potential role of Ps. columella in the amplification of digenean diseases in its introduced range. Phylogenetic analyses of partial sequences of the cytochrome c oxidase subunit 1 mitochondrial gene (cox 1) showed multiple lineages of Ps. columella in North and South America. Pseudosuccinea columella specimens from the present study belong to an invasive genotype that has spread globally and has been reported from Zimbabwe, Egypt, Portugal, Australia, Argentina, Colombia and New Mexico (USA). Physella acuta from the current study had a stronger genetic relationship with isolates from Canada and Iceland, than with isolates from other parts of Africa, suggesting several invasion routes into Africa. This is the first known DNA characterisation of G. chinensis from Africa. Phylogenetic reconstruction indicated multiple exit events of G. chinensis from Asia into Europe and Africa. South African isolates clustered in a recent branch containing isolates from the Czech Republic and Hong Kong, China. Considering the presence of invasive snails in all the sampling sites in the present study, it is necessary to investigate the factors that enhance their establishment and to monitor their effects on the native snail populations. [ABSTRACT FROM AUTHOR]

The genus Neosimnia P. Fisher, 1884, is reported for the first time from Indonesia in the form of several fossil species, recovered together from the Miocene deposits of Tasikmalaya, West Java. The species described closely resemble their current Atlantic counterparts, of which they exhibit all the modern characteristics. Nevertheless, they are undoubtedly new to science, as no living or fossil specimens of this genus are known from the Indian Ocean or the Western Pacific Region. [ABSTRACT FROM AUTHOR]

Three new species in the subgenus Piperamarginella, genus Marginella from the Eastern Cape, South Africa, are described. This study follows on the study conducted by the author (2024) where three new species, Marginella (Piperamarginella) buffaloensis, M. (P.) lindaswartae, and M. (P.) gonubiensis were described and compared to M. (P.) monozona, M. (P.) obliqua, (P.) scitula and M. (P.) piperata. Additional sorting of Piperamarginella shells in this study resulted in the identification of three new species, described here as M. (P.) salmarosea n. sp., M. (P.) boetveldsmani n. sp., and M. (P.) florescopictorata n. sp. [ABSTRACT FROM AUTHOR]

Land snails, including some economically important species, are commonly found in forests and mountainous regions of Türkiye. Türkiye's large geomorphological region and four surrounding seas, which offer a variety of malacofauna, help Türkiye achieve an endemism grade of over 65%. Despite extensive research over the past few decades, we still lack a sufficient understanding of the species identification of land snails in Türkiye, particularly in areas like forested mountain regions, and it is assumed that there are more than 1000 taxa in total. This review emphasizes the existence of invasive non-native snail species in Türkiye, such as Arion ater (Linnaeus, 1758) and Arion vulgaris Moquin-Tandon, 1855, which have a negative impact on agricultural and horticultural output. In addition to these species, Theba pisana, Cornu aspersum, Xeropicta derbentina, Xeropicta krynickii, Cernuella virgata and Eobania vermiculata are also found in Türkiye as non- native land snail species. Moreover, it also places a strong emphasis on the necessity of managing invasive species to reduce their detrimental effects on natural ecosystems by giving examples from the world and covers the predictions about the possible threats that the presence of non-native invasive land snail species in Türkiye may pose in the future. [ABSTRACT FROM AUTHOR]

Genetic diversity within a species can be shaped by abiotic factors, such as climate and geography. We aimed to ascertain the relative importance of these two abiotic factors to Indrella ampulla , a monotypic snail species from the Western Ghats, India, that has three colour morphs with some overlapping distributions. We also wanted to investigate whether these colour morphs represent divergent lineages or incipient species. We sequenced one nuclear and two mitochondrial genes from 32 individuals of I. ampulla. We used phylogenetic, population genetic, and niche modelling tools to address these questions. The results suggested that the colour morphs were not reciprocally monophyletic and exhibited considerable niche overlap, suggesting that they cannot be considered as incipient species. Furthermore, the results showed that the impact of palaeoclimatic oscillations in shaping the genetic diversity of this species cannot be determined conclusively. The Palghat Gap seems to have shaped the genetic diversity in this group to a certain degree. The colour morph distributed south of the Palghat Gap did not show admixture and exhibited the least amount of niche overlap with the other morphs. The geography of the landscape seems to have played a prominent role in shaping genetic diversity in this species. [ABSTRACT FROM AUTHOR]

The almost complete absence of regulations to protect invertebrates is a common condition in legal systems, including the European one, especially when it comes to invertebrates intended for human consumption. Thus, in the vast majority of cases, edible invertebrates do not receive even the most basic protection at slaughter. Despite recent research indicating that invertebrates are capable of feeling pain and stress, the humane step of stunning is not used on them. This is also the case for land snails, which are gastropod invertebrates whose consumption has now reached significant levels, already involving tonnes and that is expected to increase significantly as edible snail farming becomes more popular as a relatively low-cost, easy-to-perform, and sustainable alternative animal husbandry, thereby making land snails an increasingly economically important species. This paper presents and investigates a proposed stunning method based on the immersion of mollusks in CO2-supplemented and refrigerated water that could be used in the snail meat production chain to reduce the slaughter suffering of millions of these invertebrates. To this end, body condition descriptors (hemolymph parameters) in snails were determined before and after CO2 treatment in cold water, while generating useful data for defining a preliminary set of reference intervals for basal values. [ABSTRACT FROM AUTHOR]

The marine animal phylum Placozoa is characterized by a poorly explored cryptic biodiversity combined with very limited knowledge of their ecology. While placozoans are typically found as part of the epibenthos of coastal waters, known placozoan predators, namely small, shell‐less sea slugs belonging to the family Rhodopidae (Mollusca: Gastropoda: Heterobranchia), inhabit the interstitium of seafloor sediment. In order to gain further insights into this predator–prey relationship and to expand our understanding of placozoan ecological niches, we screened publicly available whole‐body metagenomic data from two rhodopid specimens collected from coastal sediments. Our analysis not only revealed the signatures of three previously unknown placozoan lineages in these sea slug samples but also enabled the assembly of three complete and two partial mitochondrial chromosomes belonging to four previously described placozoan genera, substantially extending the picture of placozoan biodiversity. Our findings further refine the molecular phylogeny of the Placozoa, corroborate the recently established taxonomic ranks in this phylum, and provide molecular support that known placozoan clades should be referred to as genera. We finally discuss the main finding of our study – the presence of placozoans in the sea floor sediment interstitium – in the context of their ecological, biological, and natural history implications. [ABSTRACT FROM AUTHOR]

The role of DNA methylation in mollusks is just beginning to be understood. This review synthesizes current knowledge on this potent molecular hallmark of epigenetic control in gastropods—the largest class of mollusks and ubiquitous inhabitants of diverse habitats. Their DNA methylation machinery shows a high degree of conservation in CG maintenance methylation mechanisms, driven mainly by DNMT1 homologues, and the presence of MBD2 and MBD2/3 proteins as DNA methylation readers. The mosaic-like DNA methylation landscape occurs mainly in a CG context and is primarily confined to gene bodies and housekeeping genes. DNA methylation emerges as a critical regulator of reproduction, development, and adaptation, with tissue-specific patterns being observed in gonadal structures. Its dynamics also serve as an important regulatory mechanism underlying learning and memory processes. DNA methylation can be affected by various environmental stimuli, including as pathogens and abiotic stresses, potentially impacting phenotypic variation and population diversity. Overall, the features of DNA methylation in gastropods are complex, being an essential part of their epigenome. However, comprehensive studies integrating developmental stages, tissues, and environmental conditions, functional annotation of methylated regions, and integrated genomic-epigenomic analyses are lacking. Addressing these knowledge gaps will advance our understanding of gastropod biology, ecology, and evolution. [ABSTRACT FROM AUTHOR]

The current study revises the systematic taxonomy of Figuladra, a genus of camaenid land snails endemic to eastern Queensland, based on the investigation of many recently collected ethanol-preserved samples as well as historic museum material, including types. We employed comparative analyses to investigate the variation in morphological features (shell, penial anatomy) and performed phylogenetic analyses of mitochondrial 16S rDNA sequences to test species hypotheses. Phylogenetic analyses recovered three principal mitochondrial clades, one occurring in mid-east Queensland, one in south-east Queensland, and another in the upland areas of south-east Queensland. We recognise altogether 15 accepted species, including four that are newly described herein (i.e.,Figuladra finlaysoni sp. nov., F. robertirwini sp. nov., F. bromileyorum sp. nov. and F. vidulus sp. nov.). The status of 11 previously described species has been assessed and revised diagnoses are provided for each of these. Species of the south-east Queensland clade revealed comparatively low levels of genetic and morphological differentiation and may represent examples of more recent, conceivably ongoing, speciation. Figuladra species have allopatric distributions with their ranges being separated by altitudinal or riverine barriers. Particularly the St Lawrence Gap dry corridor has been identified as a major biogeographic barrier separating two principal clades of Figuladra. [ABSTRACT FROM AUTHOR]

Parasites exhibit high diversity in various ecosystems. Habitat selection has played an important role in the diversification of parasites by facilitating intra-host speciation and repeated shifts to a single host species by multiple parasite taxa. In this study, we investigated habitat selection in two gastropod species, Melanella cf. acicula and Peasistilifer nitidula (Caenogastropoda: Vanikoroidea: Eulimidae), that are parasitic on the black sea cucumber Holothuria atra in southwestern Japan. The number and position of parasites were observed for 335 hosts; in total, 89 individuals of M. cf. acicula and 194 of P. nitidula were found. Melanella cf. acicula exhibited strong habitat selection, with 70 individuals (78.7%) attached around the host's mouth, whereas P. nitidula had relatively low infection site specificity. This suggests that the two parasite species have different feeding habits. Molecular phylogenetic analysis verified their non-monophyletic relationship, indicating that they likely made independent host shifts to H. atra. The observed difference in habitat preference, as well as the abundance of suitable habitats, may have contributed to the repeated host shifts and sympatric distribution of M. cf. acicula and P. nitidula. Our phylogenetic analysis also revealed the non-monophyly of eulimids parasitising holothuroids, as in asteroid and ophiuroid parasitic taxa. [ABSTRACT FROM AUTHOR]

The monospecific genus Tartessiberus was described in the year 2021 including a single species (T. cilbanus). However, its description relied solely on morphological and anatomical data. In the present work, we use a fraction of the mitochondrial DNA cytochrome oxidase subunit I (COI), 16S ribosomal RNA (16S rRNA) and the nuclear large ribosomal subunit (LSU) to clarify its validity through phylogenetic positioning. Knowledge of the distribution of this species is also improved by citing new locations and expanding the geographical range to approximately 200 km2. Additionally, a morphometric analysis of 259 shells is presented for comparisons with shells of the Iberus marmoratus complex and testing the power of conchological features as a tool for specimen identification. The relatively high conchological variability found for T. cilbanus, together with the discovery of populations with intermediate conchological features between T. cilbanus and other closely related taxa, suggest that the determination of this species should be based on genetic criteria. Our molecular analyses demonstrate that T. cilbanus belongs to the Iberus genus, and thus, we proceed to update its taxonomic status to Iberus cilbanus comb. nov., and, thus, to consider Tartessiberus from now on as a junior synonym of Iberus. [ABSTRACT FROM AUTHOR]

Inundative biological control (biocontrol) efforts in pest management lead to the mass distribution of commercialized biocontrol agents. Many 'biocontrol gone awry' incidents have resulted in disastrous biodiversity impacts, leading to increased scrutiny of biocontrol efforts. The nematode Phasmarhabditis hermaphrodita is sold as a biocontrol agent on three continents and targets pest gastropods such as Deroceras reticulatum, the Grey Field Slug; P. hermaphrodita is not presently approved for use in the United States. Investigations into the potential for P. hermaphrodita to infect non-target gastropod species of conservation relevance, however, are limited. We examined the effects of three strains of P. hermaphrodita on mortality in Monadenia fidelis, the Pacific Sideband, a snail species endemic to the Pacific Northwest of North America, in laboratory conditions. Across a 71-day laboratory infectivity assay, snails exposed to each of the three nematode strains, each analyzed at two doses, experienced a mean 50% mortality by days 20–42. All nematode-treated snails were dead by the end of the study. By contrast, 30/30 water-control snails experienced no mortality. Nematodes killed smaller, juvenile-stage snails significantly faster than those in larger and more developmentally advanced hosts. Our results provide direct evidence that the biocontrol nematode P. hermaphrodita infects and kills M. fidelis, a non-target gastropod species endemic to the Pacific Northwest, in laboratory conditions. This study suggests that introduction of P. hermaphrodita to new ecosystems might negatively impact endemic gastropod biodiversity and advocates for further investigation of non-target effects, including in conditions closer to the natural environments of non-target species. [ABSTRACT FROM AUTHOR]

The article explores the predatory behavior of Anthracalaus sakaguchii, a species of click beetle larvae found in the Ryukyu Islands of Japan. These larvae are unique in their ambush hunting technique, where they drag land snails into their underground burrows and consume their soft body parts. This behavior has not been observed in other snail-eating predators. The article provides detailed descriptions and images of the larvae and their burrows, and suggests further research on their feeding habits and attraction mechanisms. The conservation status of related species is also mentioned. [Extracted from the article]

Olivancillaria carcellesi occurs in shallow sandy shores from north Patagonia, in intertidal and subtidal sandy bottoms. Females of O. carcellesi exhibited a remarkable specificity for spawning on the shells of living males and females, indiscriminately, of the buccinanopsid Buccinastrum deforme, measuring 26.9 ± 4.7 mm in shell length. The egg capsule was semispherical and attached to B. deforme shells by a small elliptical and wide base. The capsule was translucid when spawned, with a thick and semirigid wall and a hatching aperture of 1.8 ± 0.1 mm (n = 111) in diameter. Each egg capsule contained a single egg that measured 1367 ± 34 μm (n = 5) in diameter before cleavage. The embryo developed a small bilobed velum and an operculum, which were both lost before hatching as a crawling juvenile of 1762 ± 47 μm (n = 28) in shell length. As in other species in the genus, the eggs of O. carcellesi are among the largest in the caenogastropods with direct development. The time from oviposition to hatching is estimated to be approximately 6 months. [ABSTRACT FROM AUTHOR]

Mucus is a defining feature of many gastropod phenotypes. Its material properties are a product of selection acting on the relationship between mucus composition, structure and performance; however, to date, there are very few studies addressing this. Here, we introduce attenuated total reflection Fourier transform infrared (FTIR) spectroscopy as an accessible analytical technique to record, identify and classify gastropod locomotive mucus, as deposited, with practically no intervention. Advancing the field beyond previous spectroscopic studies, we also probe mucus response to a temperature increase, determining its propensity to remain hydrated (i.e. resist denaturation) and serving as the basis for building cladograms based on spectral similarities. Specifically, the relative content of proteins, their secondary structures, protein-carbohydrate interactions, and thermal stability were investigated and shown to have significant variation between species. Collating and comparing over 648 spectra across 12 species and 7 superfamilies, we report that it is even possible to classify gastropods based solely on their secreted pedal mucus. This was further compared to previously published phylogenetic data and taxonomies enabling a 100% hit rate of genus assignment, implying that mucus FTIR may also be a powerful tool for field-based biodiversity studies. [ABSTRACT FROM AUTHOR]

This article examines the concept of holes in philosophy and their practical implications in zoological morphology, specifically in gastropod shells. The authors introduce different types of openings in gastropod shells, such as the true umbilicus, pseudoumbilicus, and a newly identified opening called the hollow newel. They propose that the axial openings in gastropod shells be designated as hollow newels, which lack complete inner shell walls forming the columella. The authors compare this concept to spiral staircases without a central supporting pillar. The text explores the presence of a hole, known as the "HN," in certain gastropod shells, discussing its attachment points for muscles and various character states associated with this feature. The authors conducted a survey and found that HNs are primarily found in turritellids. The text also delves into the potential functions and evolutionary significance of the HN. Overall, the article emphasizes the need for further research and examination of physical specimens to gain a better understanding of gastropod evolution and ecology. [Extracted from the article]

Examining activity patterns is essential in understanding gastropod feeding and movement ecology. However, the diel activity patterns of large-bodied gastropods, such as Cassis cornuta , remain poorly studied. Here, we conducted outdoor hatchery-based experiments to examine the diel activity patterns of C. cornuta adults and juveniles under natural sunlight and photoperiod. Activities of C. cornuta , such as crawling, hunting, feeding, burrowing and resting on the substratum, were examined every hour for 3 days. Although most individuals were inactive for a greater part of the observation period, active behaviours were recorded for some individuals during both daytime and nighttime, suggesting that C. cornuta is cathemeral, as supported by a nonsignificant result from a Rayleigh's test of uniformity. A higher proportion of adult and juvenile C. cornuta were inactive, either burrowed or resting on the substratum, during the 24-h period. Peak activity time for juveniles started at 20:00, with up to 50% of individuals active, while peak activity time for adults started at 21:00, with up to 20% of active individuals. Adults spent more time resting aboveground, whereas juveniles spent more time burrowed under the sand when not feeding. Juveniles hunted more frequently and spent more time feeding compared to adults. Additionally, juveniles crawled faster and were more successful in capturing sea urchins than adults. The information on variability in the diel activity patterns and movement rates between adult and juvenile C. cornuta would allow further demographic studies, and provide insights into possible conservation strategies for this species. [ABSTRACT FROM AUTHOR]

The neritid snail Theodoxus fluviatilis is found across habitats differing in salinity, from shallow waters along the coast of the Baltic Sea to lakes throughout Europe. Living close to the water surface makes this species vulnerable to changes in salinity in their natural habitat, and the lack of a free-swimming larval stage limits this species' dispersal. Together, these factors have resulted in a patchy distribution of quite isolated populations differing in their salinity tolerances. In preparation for investigating the mechanisms underlying the physiological differences in osmoregulation between populations that cannot be explained solely by phenotypic plasticity, we present here an annotated draft genome assembly for T. fluviatilis , generated using PacBio long reads, Illumina short reads, and transcriptomic data. While the total assembly size (1045 kb) is similar to those of related species, it remains highly fragmented (N scaffolds = 35,695; N50 = 74 kb) though moderately high in complete gene content (BUSCO single copy complete: 74.3%, duplicate: 2.6%, fragmented: 10.6%, missing: 12.5% using metazoa n = 954). Nevertheless, we were able to generate gene annotations of 21,220 protein-coding genes (BUSCO single copy complete: 65.1%, duplicate: 16.7%, fragmented: 9.1%, missing: 9.1% using metazoa n = 954). Not only will this genome facilitate comparative evolutionary studies across Gastropoda, as this is the first genome assembly for the basal snail family Neritidae, it will also greatly facilitate the study of salinity tolerance in this species. Additionally, we discuss the challenges of working with a species where high molecular weight DNA isolation is very difficult. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to determine the benthic macroinvertebrate fauna of Demre Stream in Antalya. Benthic macroinvertebrate samples were taken seasonally from 12 stations determined on Demre Stream between April 2015 and December 2015 and the obtained individuals belonging to Clitellata, Rhabditophora, Gastropoda, Insecta, and Arachnida groups Macroinvertebrate based clustering of stations was calculated by using UPGMA analysis. The lowest similarity was determined between the 3rd and 10th stations, and the highest similarity was between the 8th and 11th stations. Simpson and Shannon-Wiener diversity indices were applied to determine the diversity values of the stations. According to both diversity indices, the highest diversity value was reached at the 5th station, while the lowest diversity value was reached at the 3rd station. This study is the first study to determine the benthic fauna of the Demre Stream and therefore all the groups identified are the first records for the Demre Stream. [ABSTRACT FROM AUTHOR]

The genus Elysia comprises about one-third of the species richness in Sacoglossa. However, the species diversity in the genus remains poorly characterized in some areas like the north-eastern Atlantic and Mediterranean waters. To clarify the systematics of this genus and to characterize the species diversity in undersampled regions, we performed an integrative study based on a thorough literature review, molecular and morphological analyses, and species delimitation approaches. We conducted phylogenetic analyses of partial sequences of two mitochondrial genes (COI and 16S) and two nuclear genes (H3 , 28S) using Bayesian inference and maximum likelihood methods, which confirmed the presence of five of the recognized European Elysia species: Elysia viridis , E. timida , E. flava , E. margaritae , and E. rubeni. Moreover, a new species (Elysia azorica sp. nov.) was identified in the Azores, and E. gordanae , currently considered a junior synonym of E. margaritae , was recovered as a distinct species. In addition, we consider E. hetta as a junior synonym of E. gordanae , and E. translucens as a taxon inquirendum. Finally, the tropical E. evelinae is recorded along European coasts for the first time. Our results demonstrate the value of integrative approaches in resolving taxonomic uncertainty surrounding polymorphism and unravelling potential cases of cryptic or pseudocryptic species complexes. [ABSTRACT FROM AUTHOR]

The snail Provanna glabra is a dominant species inhabiting both hydrothermal vents and cold seeps of the Northwest Pacific Ocean. The genetic diversity and population structure of the snail from the hydrothermal vents of Okinawa Trough and a methane seep in the South China Sea were investigated using mitochondrial cytochrome c oxidase subunit I (COI) and genome‐wide single nucleotide polymorphisms (SNPs). A total of 28,805 SNPs were screened based on 2b‐RAD sequencing. Substantial genetic differences between vent and seep populations were identified based on the two datasets with FST = 0.753 (COI) and FST = 0.109 (SNPs), respectively. The results of phylogenetic tree, ADMIXTURE and principal component analysis jointly supported the population differentiation. Outlier detection confirmed the local adaptation of P. glabras populations, and the annotation of these outliers revealed that they were closely associated with processes of signal transduction, immunity, DNA repair, transposable elements and biological development. The genetic divergence observed between hydrothermal vent and methane seep P. glabra populations might be induced by the geographic barrier, limited dispersal ability and natural selection imposed by local environmental pressures from different deep‐sea habitats, e.g. chemical composition, temperature and microbes. These results provide a genetic basis for the microevolution of snails inhabiting deep‐sea chemosynthetic ecosystems. [ABSTRACT FROM AUTHOR]

A new species of pomatiopsid freshwater snail, Fenouilia undata Chen & He, sp. nov., is described from Guangxi, China, based on morphological and molecular evidence. The new species can be distinguished from its congeners by the following combination of characters: shell with low, prosocline, rounded axial ribs and fine spiral striae, broader than high; aperture broader than shell height; radula with lateral teeth have only two or three faint, wavy ridges on inner side. A molecular analysis of partial mitochondrial COI and 16S DNA sequences supports the systematic position of the new taxon. [ABSTRACT FROM AUTHOR]

Ramshorn snails from the family Planorbidae are important freshwater snails due to their low trophic level, and some of them act as intermediate hosts for zoonotic trematodes. There are about 250 species from 40 genera of Planorbidae, but only 14 species from 5 genera (Anisus, Biomphalaria, Bulinus, Gyraulus, and Planorbella) have sequenced complete mitochondrial genomes (mitogenomes). In this study, we sequenced and assembled a high-quality mitogenome of a ramshorn snail, Polypylis sp. TS-2018, which represented the first mitogenome of the genus. The mitogenome of Polypylis sp. TS-2018 is 13,749 bp in length, which is shorter than that of most gastropods. It contains 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and 2 ribosomal RNA (rRNA). We compared mitogenome characteristics, selection pressure, and gene rearrangement among all of the available mitogenomes of ramshorn snails. We found that the nonsynonymous and synonymous substitution rates (Ka/Ks) of most PCGs indicated purifying and negative selection, except for atp8 of Anisus, Biomphalaria, and Gyraulus, which indicated positive selection. We observed that transpositions and reverse transpositions occurred on 10 tRNAs and rrnS, which resulted in six gene arrangement types. We reconstructed the phylogenetic trees using the sequences of PCGs and rRNAs and strongly supported the monophyly of each genus, as well as three tribes in Planorbidae. Both the gene rearrangement and phylogenetic results suggested that Polypylis had a close relationship with Anisus and Gyraulus, while Bulinus was the sister group to all of the other genera. Our results provide useful data for further investigation of species identification, population genetics, and phylogenetics among ramshorn snails. [ABSTRACT FROM AUTHOR]

Research on complete mitochondrial genomes can help in understanding the molecular evolution and phylogenetic relationships of various species. In this study, the complete mitogenome of Hua aristarchorum was characterized to supplement the limited mitogenomic information on the genus Hua. Three distinct assembly methods, GetOrganelle, NovoPlasty and SPAdes, were used to ensure reliable assembly. The 15,691 bp mitogenome contains 37 genes and an AT-rich region. Notably, the cytochrome c oxidase subunit I (COX1) gene, commonly used for species identification, appears to be slow-evolving and less variable, which may suggest the inclusion of rapidly evolving genes (NADH dehydrogenase subunit 6 [ND6] or NADH dehydrogenase subunit 2 [ND2]) as markers in diagnostic, detection, and population genetic studies of Cerithioidea. Moreover, we identified the unreliability of annotations (e.g., the absence of annotations for NADH dehydrogenase subunit 4L [ND4L] in NC_037771) and potential misidentifications (NC_023364) in public databases, which indicate that data from public databases should be manually curated in future research. Phylogenetic analyses of Cerithioidea based on different datasets generated identical trees using maximum likelihood and Bayesian inference methods. The results confirm that Semisulcospiridae is closely related to Pleuroceridae. The sequences of Semisulcospiridae clustered into three clades, of which H. aristarchorum is one; H. aristarchorum is sister to the other two clades. The findings of this study will contribute to a better understanding of the characteristics of the H. aristarchorum mitogenome and the phylogenetic relationships of Semisulcospiridae. The inclusion of further mitochondrial genome sequences will improve knowledge of the phylogeny and origin of Cerithioidea. [ABSTRACT FROM AUTHOR]

The fossils of the genus Yochelcionella Runnegar et Pojeta, 1974 from the Salaanygol and Khairkhan formations of the Zavkhan structural-facies zone were re-studied as a part of the general revision of malacofauna from the Vendian–Lower Cambrian deposits of Western Mongolia. It was found out that studied strata, in addition to the earlier reported species Y. parva Zhegallo, 1996 and Y. crassa Zhegallo, 1996, contain two other forms identified as Y. chinensis Pei, 1985 and Yochelcionella sp. The species Y. chinensis has the widest distribution among representatives of the genus Yochelcionella and can be successfully used to correlate sediments of remote paleobasins. The diagnosis and composition of the genus Yochelcionella are revised, the species Y. chinensis is described. [ABSTRACT FROM AUTHOR]

Time calibrated phylogenies are typically reconstructed with fossil information but for soft‐bodied marine invertebrates that lack hard parts, a fossil record is lacking. In these cases, biogeographic calibrations or the rates of divergence for related taxa are often used. Although nudibranch phylogenies have advanced with the input of molecular data, no study has derived a divergence rate for this diverse group of invertebrates. Here, we use an updated closure date for the Isthmus of Panama (2.8 Ma) to derive the first divergence rates for chromodorid nudibranchs using multigene data from a geminate pair with broad phylogeographic sampling. Examining the species Chromolaichma sedna (Marcus & Marcus, 1967), we uncover deep divergences among eastern Pacific and western Atlantic clades and we erect a new species designation for the latter (Chromolaichma hemera sp. nov.). Next, we discover extensive phylogeographic structure within C. hemera sp. nov. sensu lato, thereby refuting the hypothesis of a recent introduction. Lastly, we derive divergence rates for mitochondrial and nuclear loci that exceed known rates for other gastropods and we highlight significant rate heterogeneity both among markers and taxa. Together, these findings improve understanding of nudibranch systematics and provide rates useful to apply to divergence scenarios in this diverse group. [ABSTRACT FROM AUTHOR]

Land snails are among Chile's least studied invertebrates. Their natural history and ecology are poorly studied, even when it comes to striking species such as the black snail Macrocyclis peruvianus. This large and easily recognizable species inhabits the forest floor of southern Chile; however, we do not know its eating habits. In this natural history note, we describe the first records of mycophagy in M. peruvianus in native Chilean forests. The records were obtained thanks to citizen science (iNaturalist, Instagram and Facebook), which provided a complete data set with habitat remarks. We registered 21 records of mycophagy, from which we identified three fungus species (Marasmiellus alliodorus, Aleurodiscus vitellinus and Grifola gargal) and five genera (Armillaria, Boletus, Mycena, Pholiota and Ramaria). Of the consumed fungi, 58.82% grew in coarse woody debris and 64.70% belong to the order Agaricales, followed by Boletales, Gomphales, Russulales and Polyporales. In addition, we described the first record of M. peruvianus feeding on the native land snail Plectostylus peruvianus. Coarse woody debris could be a key element for black snails because their frequent food – the Agaricales fungi species – grows on them. Finally, M. peruvianus feeding on other native land snails could be rare in the wild because they co‐occur in the same distribution but in different microhabitats. [ABSTRACT FROM AUTHOR]

A new species of Corinnaeturris from the southeastern Gulf of Mexico is described and compared with C. leucomata (Dall, 1881) and C. angularis Figueira & Absalão, 2010, the only two species of that genus heretofore described (Worms, 2023). [ABSTRACT FROM AUTHOR]

Three new species of gastropods are described from the Gulf of Mexico. Theseinclude: Fasciolaria ixchel n.sp. (Fasciolariidae) from near Isla Mujeres on the eastern side of the Yucatan Peninsula of Mexico; Jaspidiconus forticostatus n.sp. (Conidae) from the Big Bend area of northwestern Florida; and Jaspidiconus hortusensis n.sp. (Conidae) from the West Flower Garden Reef southeast of Galveston, Texas. The eastern Yucatan fasciolariid is the newest member of a previously-overlooked complex that contains four closely-related Fasciolaria s.s. species that are endemic to the Gulf of Mexico. The two new cones are members of a complex containing ten species of Jaspidiconus that are now known to inhabit shallow water areas around the Gulf of Mexico. [ABSTRACT FROM AUTHOR]

Three new species in the subgenus Piperamarginella, genus Marginella from the Eastern Cape, South Africa, are described. The study originated when material, all identified as M. (P.) monozona W.H. Turton, 1932, turned out to be four different species. The following new species are described: M. (P.) buffaloensis n. sp., M. (P.) lindaswartae n. sp. and M. (P.) gonubiensis n. sp. [ABSTRACT FROM AUTHOR]

A new species of Bistolida Cossmann, 1920 is described fromthe Miocene of theCibalong area, Tasikmalaya Regency of western Java, Indonesia. Morphological analyses of theshell dimensions, outline, extremities, aperture shape, and apertural teeth shows a combinationofcharacters that are typical of the genus Bistolida. Although the genus has not previouslybeenreported from Java, its presence in the Miocene fossil record is supported by the six specimens that are shown here. [ABSTRACT FROM AUTHOR]

The fifth mass extinction event (MEE) at the Cretaceous–Palaeogene (K–Pg) boundary 66 million years ago (Ma) led to massive species loss but also triggered the diversification of higher taxa. Five models have been proposed depending on whether this diversification occurred before, during or after the K–Pg boundary and the rate of species accumulation. While the effects of the K–Pg MEE on vertebrate evolution are relatively well understood, the impact on invertebrates, particularly in freshwater ecosystems, remains controversial. One example is the hyperdiverse Hydrobiidae—the most species‐rich family of freshwater gastropods. Whereas some studies place its origin in the Jurassic or even Carboniferous, most fossil records postdate the K–Pg event. We therefore used robustly time‐calibrated multi‐locus phylogenies of >400 species representing >100 hydrobiid genera to unravel its evolutionary history and patterns of diversification. We found that the family started diversifying shortly after the K–Pg boundary (∼60 Ma; 95% highest posterior density 52–69 Ma). Lineage richness gradually increased to the present and phylogenetic diversity until ∼25 Ma. These findings suggest that diversification was not initially driven by ecological opportunity. Combining the two criteria of timing and rate of diversification, a soft‐explosive diversification model of aquatic vertebrates best fits the patterns observed. We also show that most higher hydrobiid taxa (i.e. subfamilies) diversified from the Middle Oligocene to Middle Miocene (i.e. 12–28 Ma). Two of the 15 major clades delimited are described here as new subfamilies (i.e. Bullaregiinae n. subfam. and Pontobelgrandiellinae n. subfam.), whose members are restricted to subterranean waters. Our results are an important contribution to understanding how the fifth MEE has shaped evolution and patterns of biodiversity in continental aquatic systems. Given the high extinction risks faced by many hydrobiids today, they also emphasise the need to study the biodiversity of vulnerable ecosystems. [ABSTRACT FROM AUTHOR]

Aim: The poleward range expansion of tropical species, and range contraction of temperate species (known as tropicalisation) has mainly been studied from an ecological perspective, with little research on its genetic consequences. Here, we used distributional and genetic data to document the consequences of tropicalisation in rocky shore gastropods and assess more broadly the future implications of tropicalisation on phylogeographic patterns. Location: Nineteen sampling sites along >3000 km of the eastern Pacific rocky intertidal zone, from the tip of the Baja California Peninsula to southern California. Taxon: Temperate gastropods: Lottia conus, L. strigatella, Fissurella volcano and Tegula gallina. Tropical gastropods: Fissurella rubropicta, Nerita funiculata and N. scabricosta. Methods: We determine historical and modern distributions of tropical and temperate species by combining historical records with current field surveys. Using a section of the cytochrome oxidase subunit I gene, we utilised comparative phylogeography, analysis of molecular variance, FST pairwise comparison, mismatch distributions of haplotype differences and neutrality tests to detect genetic signatures of tropicalisation and to better understand its consequences. Results: We identified range contractions in two temperate species and range expansion in all three tropical species. We detected genetic signatures of range expansion in the tropical species through unimodal distributions of pairwise haplotype differences and strongly negative values for the Fu and Li D and F* statistics. We found population subdivision and phylogeographic breaks in three temperate species, although the geographic location of the breaks differed among species. Main Conclusions: Genetic signatures and field surveys indicate recent range expansions in tropical species, supporting tropicalisation along the studied coastline. Conversely, we found phylogeographic breaks in temperate species, suggesting that tropicalisation may cause genetic erosion of evolutionary distinct lineages with range‐contraction. The different locations of the phylogeographic breaks among temperate species suggests that some barriers are species specific. [ABSTRACT FROM AUTHOR]

Gastropoda are an exceptionally successful group with a rich and diverse fossil record. They have conquered land and freshwater habitats multiple times independently and have dispersed across the entire globe. Since they are important constituents of fossil assemblages, they are often used for palaeoecological reconstruction, biostratigraphic correlations, and as model groups to study morphological and taxonomic evolution. While marine faunas and their evolution have been a common subject of study, the freshwater component of the fossil record has attracted much less attention, and a global overview is lacking. Here, I review the fossil record of freshwater gastropods on a global scale, ranging from their origins in the late Palaeozoic to the Pleistocene. As compiled here, the global fossil record of freshwater Gastropoda includes 5182 species in 490 genera, 44 families, and 12 superfamilies over a total of ~340 million years. Following a slow and poorly known start in the late Palaeozoic, diversity slowly increased during the Mesozoic. Diversity culminated in an all‐time high in the Neogene, relating to diversification in numerous long‐lived (ancient) lakes in Europe. I summarise well‐documented and hypothesised freshwater colonisation events and compare the patterns found in freshwater gastropods to those in land snails. Furthermore, I discuss potential preservation and sampling biases, as well as the main drivers underlying species diversification in fresh water on a larger scale. In that context, I particularly highlight the importance of long‐lived lakes as islands and archives of evolution and expand a well‐known concept in ecology and evolution to a broader spectrum: scale‐independent ecological opportunity. [ABSTRACT FROM AUTHOR]

Indoplanorbis exustus is a freshwater gastropod belonging to the family Planorbidae. This snail is widely distributed across the tropics and plays an important role as the intermediate host for trematodes. However, relatively little is understood regarding the genetic relationship between I. exustus and trematodes. The goals of this study were to investigate the current transmission status of trematode cercariae in I. exustus in Thailand and to examine the genetic diversity, genetic structure, and demographic history of I. exustus. We collected 575 I. exustus from 21 provinces across six regions of Thailand and investigated cercarial infections by using the shedding method. I. exustus from two provinces were infected with cercarial trematodes, and two types of cercarial stages were molecularly identified as furcocercous cercaria and xiphidiocercariae. Phylogenetic tree analysis based on 28S rDNA and ITS2 sequences demonstrated that furcocercous cercaria and xiphidiocercariae were closely clustered with a clade of Euclinostomum sp. and Xiphidiocercariae sp., respectively. Phylogenetic and network analyses of I. exustus haplotypes based on the COI, 16S rDNA, and ITS1 genes demonstrated four main clades. Only snails in clade A were distributed in all regions of Thailand and harbored trematode cercariae. The level of genetic diversity of I. exustus was relatively high, but most populations were not genetically different, thus suggesting the appearance of gene flow within the I. exustus populations. Overall, the haplotype network was star-shaped, thus suggesting the recent demographic expansion of populations. This result was also supported by the unimodal mode of the mismatch distribution graph and the large negative values of the neutrality tests. Therefore, the I. exustus snail was likely another freshwater snail of the invasive species in Thailand. This information will aid in monitoring the spread of the parasitic trematodes carried by I. exustus from different populations. [ABSTRACT FROM AUTHOR]

Simple Summary: Lophiotoma leucotropis belongs to the Turridae and is a carnivorous snail that is widely distributed in shallow sea sand and intertidal zones around the world. Currently, the mitochondrial genome sequence of L. leucotropis has not been explored. And there is also great controversy over whether the order Neogastropoda to which L. leucotropis belongs is monophyletic. We sequenced the mitogenome of L. leucotropis and analyzed its basic gene characteristics. We found that it contains a total of 37 gene contents. Similar to species in the Turridae family, it has a higher content of AT bases and a preference for some codons. The selection pressure analysis results showed purification selection effects, and through comparison with other species in Turridae, it was found that the gene sequence of this species is conserved, which helps to deepen the understanding of the Turridae. We constructed a phylogenetic tree using the 13 protein coding genes of Neogastropoda and concluded that the order is monophyletic. This result is a supplement and validation to the research on the evolutionary status of Neogastropoda and also provides reference for the species classification and germplasm resource development of Neogastropoda. Neogastropoda is a group of marine organisms with an extremely wide distribution that is rich in species and economic and ornamental values, the classification of species in this order has been ongoing for a long time, but there is still a great controversy about whether this order is monophyletic. In this study, we obtained the complete mitogenome of Lophiotoma leucotropis by next-generation sequencing and analyzed the basic structural features of the genome, and we found that the number of genes was consistent with that of most of the Neogastropoda snails, containing 37 genes, including 13 protein-coding genes (PCGs), 2 rRNAs, and 22 tRNAs. Analyzing base content, amino acid content, codon usage preference, and tRNA structure, the mitogenomes of eight species of Turridae were selected for analysis of selection pressures, and it was found that the evolution of species in this family was affected by purifying selection. In addition, by analyzing the rearrangement characteristics, it was found that the sequence of L. leucotropis was consistent with the Conoidea consensus order, and four of the eight species involved in the analysis showed rearrangements. Finally, we constructed a phylogenetic tree by combining PCGs of 60 species within Caenogastropoda and found Neogastropoda to be a monophyletic group, validating the results of morphological classification. The results will provide more references for the classification and species evolution of Neogastropoda, as well as phylogenetic analysis. [ABSTRACT FROM AUTHOR]

The land snail faunas of limestone gorges of Romanian Carpathians were sampled to test the effect of geographic and environmental factors on the malacofauna richness and composition. A total of 134 sites within 28 limestone gorges were surveyed during 2011–2019 using a combined strategy of visual search and litter/topsoil analysis. Environmental variables such as geographic location, altitude, climate, microhabitat type, dominant vegetation, tree cover and width of the gorge were recorded to detect the relationship with species richness and composition. While the numbers of species, their identities and their abundance varied greatly among samples, both presence and absence data and quantitative multivariate analyses showed that region and climate or altitude (both strongly associated with region) accounted for far more variation than differences in tree cover and dominant microhabitat. Nevertheless, the effects of different habitat preferences were evident. The mixture of species with very restricted ranges within this Pleistocene refugium and those that have spread widely during the Holocene raise questions about the meaning of region when related to local richness and composition. [ABSTRACT FROM AUTHOR]

Background: How novel phenotypes originate from conserved genes, processes, and tissues remains a major question in biology. Research that sets out to answer this question often focuses on the conserved genes and processes involved, an approach that explicitly excludes the impact of genetic elements that may be classified as clade-specific, even though many of these genes are known to be important for many novel, or clade-restricted, phenotypes. This is especially true for understudied phyla such as mollusks, where limited genomic and functional biology resources for members of this phylum have long hindered assessments of genetic homology and function. To address this gap, we constructed a chromosome-level genome for the gastropod Berghia stephanieae (Valdés, 2005) to investigate the expression of clade-specific genes across both novel and conserved tissue types in this species. Results: The final assembled and filtered Berghia genome is comparable to other high-quality mollusk genomes in terms of size (1.05 Gb) and number of predicted genes (24,960 genes) and is highly contiguous. The proportion of upregulated, clade-specific genes varied across tissues, but with no clear trend between the proportion of clade-specific genes and the novelty of the tissue. However, more complex tissue like the brain had the highest total number of upregulated, clade-specific genes, though the ratio of upregulated clade-specific genes to the total number of upregulated genes was low. Conclusions: Our results, when combined with previous research on the impact of novel genes on phenotypic evolution, highlight the fact that the complexity of the novel tissue or behavior, the type of novelty, and the developmental timing of evolutionary modifications will all influence how novel and conserved genes interact to generate diversity. [ABSTRACT FROM AUTHOR]

Marine reserves (MRs) are implemented worldwide to protect, restore, and manage marine ecosystems and species. However, it is important to document the positive effects those marine reserves have on slow-growth, temperate invertebrates such as abalone. Abalone, Haliotis spp., are marine gastropods of high economic value extracted worldwide for decades, which has led to fisheries-driven population decreases. In this work, we focused on a case study and assessed the short-term (1–2 years) effects of marine reserves established and managed by a local fishing cooperative at Guadalupe Island, Mexico. We evaluated the population status of green abalone, H. fulgens, by conducting (1) an assessment of the green abalone population around Guadalupe Island through subtidal monitoring and (2) an evaluation of the effect of two recently established marine reserves on population parameters such as the increase in density (individuals·m2), biomass, number of aggregated abalone, egg production, and proportion of individuals bigger than 150 mm (minimum harvest size) compared to fished areas. To assess the population around Guadalupe Island, we surveyed 11,160 m2 during 2020 and 2021. We recorded 2327 green abalones with a mean ± SE shell length of 135.978 ± 0.83 mm and a mean density of 0.21 ± 0.02 individuals·m2. All variables were statistically higher at the MRs except for shell length in 2021. In this work, we report for the first time the green abalone population status at Guadalupe Island and a positive short-term biological response to community-based marine reserves. This study suggests that a network of MRs combined with good management could help abalone populations in the short term in Guadalupe Island, potentially leading to more sustainable fishing practices and social-ecological resilience. [ABSTRACT FROM AUTHOR]

Consistent species identification is foundational to biological research and requires coordination among a diversity of researchers and institutions. However, such consistency may be hindered for rare organisms where specimens, identification resources, and taxonomic experts are few. This is often the case for deep-sea taxonomic groups. For example, the deep-sea gastropod genus Provanna Dall, 1918 is common at chemosynthetic sites throughout the world's oceans, yet no formal guide to these species has yet been produced. Recent exploration has recovered new specimens of Provanna from hydrocarbon seeps off the Pacific Costa Rica Margin. The current work assesses the species identity of these specimens using shell morphology, radular morphology, and genetic barcoding (mitochondrial CO1 and nuclear H3). Records of occurrence for P. laevis Warén & Ponder, 1991, P. ios Warén & Bouchet, 1986, and P. pacifica Warén & Bouchet, 1986 are herein presented from the Costa Rica Margin. A critical taxonomic review of the 29 extant species within this genus was conducted and their genetic, morphological, and biogeographical distinction assessed. In this review, genetic and morphological support was found for nearly all current species delineations except for P. glabra Okutani et al., 1992, syn. nov. and P. laevis, syn. nov., which are herein synonymized to P. laevis, and for P. ios, syn. nov. and P. goniata Warén & Bouchet, 1986, syn. nov., which are synonymized to P. ios. Finally, the first species identification key for the extant species in this genus is presented. This work clarifies the taxonomy and systematics of this deep-sea gastropod genus and contributes a novel polytomous key for use in future research. [ABSTRACT FROM AUTHOR]

Mussels form extensive beds in rocky intertidal habitats on temperate seashores worldwide. They are foundation species because their beds host many invertebrates. Mussels and their associated species differ taxonomically among biogeographic regions, but all mussel beds exhibit similar structural and functional properties. Therefore, we investigated if rocky-intertidal mussel beds from around the globe host associated communities that are functionally similar despite their underlying taxonomic differences. We gathered datasets on the abundance of invertebrates found in rocky-intertidal mussel beds from the eastern and western boundaries of the Pacific and Atlantic Oceans from both hemispheres and, then, we compared their taxonomic and functional properties. Taxonomic composition differed markedly among coasts when analyzed at the taxonomic resolution reported by the surveys (often species). However, taxonomic groups with similar ecologies (28 groups including barnacles, decapods, gastropods, polychaetes, etc.) were more universally present in mussel beds. Concomitantly, functional categories of trophic level, body type, and mobility were almost always present on all studied coasts. These taxonomic groups and trait categories, however, showed regional patterns based on their relative abundances. Overall, the ability of mussel beds to host a core community type based on taxonomic groups and functional traits emphasizes their importance for biodiversity and community functioning, making them critical organisms to preserve. [ABSTRACT FROM AUTHOR]

Tehran province as a diverse habitat for different animal species, has the potential to support many land molluscs species. However, a little glimpse of the research on malacology shows that Tehran province is probably the least well-studied area for land snails in Iran. Herein, the very first comprehensive study about the land snails collected from Tehran province in addition to the previous scientific document is presented. The data included here are based on the field investigations and the published records by different authors from 2008 to 2023 This checklist is collectively composed of 22 species belonging to 16 genera under nine families from different parts of Tehran province. However, some areas of Tehran province have not been investigated in terms of the diversity of snail species. The outcome of this report shows that more research is needed on the species diversity of terrestrial snails in Tehran province. [ABSTRACT FROM AUTHOR]

The rock units in the Gawran Gorge, Sagirma Mountains (from the High Folded Zone), near the Sulaimaniyah city, in the Kurdistan Region, NE Iraq, were investigated in order to describe and biostratigraphically date the sedimentary succession. Twenty-seven species of larger benthic foraminifera were identified belonging to 16 genera. Several other fossil groups were also recognized, including echinoid, bryozoan, bivalve, gastropods and coral remains. Two biozones were recognized--the Praerhapydionina delicata-Austrotrillina asmariensis/Peneroplis evolutus Assemblage Zone and the P. delicata/Austrotrillina howchini Interval Zone, which indicate a late Oligocene-lowermost Miocene age for the succession. This section was correlated to the surrounding successions having a similar age in the High Folded Zone of Iraq, and to sediments in other countries, so as to indicate the wider distribution of the lithostratigraphic unit. [ABSTRACT FROM AUTHOR]

This paper introduces Xanthomelon amurndamilumila sp. nov. , a newly-discovered land snail species inhabiting the North East Isles, offshore from Groote Eylandt (= Ayangkidarrba), north-western Gulf of Carpentaria, in the Northern Territory, Australia. Specimens of this species were first collected during the 2021 Bush Blitz expedition to Groote Eylandt, a large offshore archipelago previously unexplored for land snails. The taxonomic status of the new species was established through a comprehensive analysis of comparative morphology and mitochondrial genetics: X. amurndamilumila forms a maximally supported clade closely related to X. arnhemense and is characterised by a unique combination of morphological characteristics, including smaller shell size, distinctive sculpture of collabral ridges and specific features of its reproductive anatomy. The genetic divergence and phylogenetic relationships suggest historical isolation. While the discovery of X. amurndamilumila sp. nov. enriches our understanding of land snail diversity in the Northern Territory, its conservation status is of concern on North East Island because of habitat degradation caused by feral deer. [ABSTRACT FROM AUTHOR]