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There is a marked disparity in the state of knowledge of Holartic x Neotropical species of the freshwater snail family Physidae; the incipiency of data on Neotropical physids reflecting the lower number of dedicated specialists. The gaps in the knowledge on Neotropical physids have led to historical uncertainty about species validity. Revisiting the species is essential to reduce taxonomic impediment and delineating their probable distribution is the first step to attain this purpose. We aimed at critically analyze occurrence records of South American physids, compiled through an intensive search in the literature, biodiversity and molecular databases. We present a provisional characterization of the distribution of this family in South America, considering the probable versus the poorly documented distribution of the species. The critical underrepresentation of South American physids in collections, molecular databases and literature reinforces the role of taxonomic impediment in delaying the advance of the knowledge on species diversity. Malacological collections represented the main source of records, evidencing the relevance of unpublished data associated to specimens to assess distributional information on neglected groups. As most of the species are represented by shells, the reassessment of species identity and distribution must be done, using molecular and anatomical criteria for species delimitation.

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Land snails are a destructive agricultural pest in economic crops, but the populations for that pest are highly influenced by temperature and humidity, therefore climatic changes affected their behavior, distribution and population dynamics, for these reasons researchers should follow up on the changes in their behavior, distribution, and population dynamics. In this study, a survey study was conducted to define land snail species existing at Sharkia Governorate, Egypt, from January 2019 to March 2022 in horticultural, vegetable, and field crops and study the population dynamics for the dominant land snail species. Results showed that there are six species of land snails, these species were, Monacha cartusiana, Succinea putris, Eobania vermiculata, Theba pisana, Helicella vestalis, and Cochlicella acuta. The population dynamics of two prevalent land snail species (M. cartusiana and S. putris), were conducted during two successive growing seasons, the Egyptian clover harbored the highest number of M. cartusiana followed by wheat, while the onion was the lowest one during the study period. In the same trends, the land snail S. putris recorded the highest numbers during the growing season of the Egyptian clover crop. Finally, it is concluded that the land snail M. cartusiana considered the first grade of infestation existed everywhere at Sharkia Governorate, and the population density of the land snail is increase gradually after winter till reach the maximum density in spring.

Os caracóis terrestres são pragas agrícolas destrutivas em cultivos econômicos, todavia, as populações dessa praga são altamente influenciadas pela temperatura e umidade, portanto as mudanças climáticas afetam seu comportamento, distribuição e dinâmica populacional, e, por essas razões, os pesquisadores devem acompanhar as mudanças em seu comportamento, distribuição e dinâmica populacional. O presente trabalho foi realizado para definir as espécies de caracóis terrestres existentes na província de Sharkia, no Egito, de janeiro de 2019 a março de 2022 em culturas hortícolas, vegetais e de campo, e estudar a dinâmica populacional das espécies dominantes de caracóis terrestres. Os resultados mostraram que existem seis espécies de caracóis terrestres, essas espécies foram Monacha cartusiana, Succinea putris, Eobania vermiculata, Theba pisana, Helicella vestalis e Cochlicella acuta. A dinâmica populacional de duas espécies predominantes de caracóis terrestres (M. cartusiana e S. putris), foi conduzida durante duas safras sucessivas, o trevo egípcio abrigou o maior número de M. cartusiana seguido pelo trigo, enquanto a cebola foi o menor durante o período de estudo. Seguindo as mesmas tendências, o caracol terrestre S. putris registrou os números mais altos durante a estação de crescimento da cultura do trevo egípcio. Finalmente, conclui-se que o caracol terrestre M. cartusiana, considerado o primeiro grau de infestação, está presente em toda a província de Sharkia, e a densidade populacional do caracol terrestre aumenta gradualmente após o inverno até atingir a densidade máxima na primavera.

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Very little is known about the malacofauna in district Swat of Khyber Pakhtunkhwa province, situated in the Northern part of Pakistan. The Swat valley possesses a variety of suitable environmental conditions, providing different types of habitats for both flora and fauna. Taken into consideration these points, the present study was conducted to explore the terrestrial snails diversity in agricultural and non-agricultural fields in the lower Swat valley. A total of 417 shells were collected from three sites: Kokarai, Kanju Township, and Deolai. Based on conchological features, three families: Bradybaenidae, Hygromiidae, and Zonitidae were identified using different terrestrial snail keys. In Kokarai and Deolai, shells of members of all the above-mentioned families were found from agricultural fields. In Kanju Township, shells of members of the family Bradybaenidae and Zonitidae were found. From these findings, it was concluded that district Swat possesses a significant malacofauna which was unexplored before and aided more to the existing literature on malacofauna. It also supports the idea that the agroecosystem is rich in species diversity. Further in-depth and extensive study is recommended to be carried out for a detailed taxonomy of the described terrestrial gastropod families.

Muito pouco se sabe sobre a malacofauna no distrito de Swat, na província de Khyber Pakhtunkhwa, situada na parte norte do Paquistão. O vale do Swat possui uma variedade de condições ambientais adequadas, proporcionando diferentes tipos de habitats para a flora e a fauna. Levando em consideração esses pontos, o presente estudo foi conduzido para explorar a diversidade dos caracóis terrestres em campos agrícolas e não agrícolas no vale inferior de Swat. Um total de 417 conchas foram coletadas em três locais: Kokarai, Kanju Township e Deolai. Com base em características concológicas, três famílias: Bradybaenidae, Hygromiidae e Zonitidae foram identificadas usando diferentes chaves de caramujos terrestres. Em Kokarai e Deolai, conchas de membros de todas as famílias mencionadas acima foram encontradas em campos agrícolas. No município de Kanju, foram encontradas conchas de membros da família Bradybaenidae e Zonitidae. A partir dessas constatações, concluiu-se que o distrito de Swat possui uma malacofauna significativa que antes era inexplorada e ajudava mais a literatura existente sobre a malacofauna. Também apoia a ideia de que o agroecossistema é rico em diversidade de espécies. Recomenda-se a realização de um estudo mais aprofundado e extenso para uma taxonomia detalhada das famílias de gastrópodes terrestres descritas.

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Very little is known about the malacofauna in district Swat of Khyber Pakhtunkhwa province, situated in the Northern part of Pakistan. The Swat valley possesses a variety of suitable environmental conditions, providing different types of habitats for both flora and fauna. Taken into consideration these points, the present study was conducted to explore the terrestrial snails diversity in agricultural and non-agricultural fields in the lower Swat valley. A total of 417 shells were collected from three sites: Kokarai, Kanju Township, and Deolai. Based on conchological features, three families: Bradybaenidae, Hygromiidae, and Zonitidae were identified using different terrestrial snail keys. In Kokarai and Deolai, shells of members of all the above-mentioned families were found from agricultural fields. In Kanju Township, shells of members of the family Bradybaenidae and Zonitidae were found. From these findings, it was concluded that district Swat possesses a significant malacofauna which was unexplored before and aided more to the existing literature on malacofauna. It also supports the idea that the agroecosystem is rich in species diversity. Further in-depth and extensive study is recommended to be carried out for a detailed taxonomy of the described terrestrial gastropod families.(AU)

Muito pouco se sabe sobre a malacofauna no distrito de Swat, na província de Khyber Pakhtunkhwa, situada na parte norte do Paquistão. O vale do Swat possui uma variedade de condições ambientais adequadas, proporcionando diferentes tipos de habitats para a flora e a fauna. Levando em consideração esses pontos, o presente estudo foi conduzido para explorar a diversidade dos caracóis terrestres em campos agrícolas e não agrícolas no vale inferior de Swat. Um total de 417 conchas foram coletadas em três locais: Kokarai, Kanju Township e Deolai. Com base em características concológicas, três famílias: Bradybaenidae, Hygromiidae e Zonitidae foram identificadas usando diferentes chaves de caramujos terrestres. Em Kokarai e Deolai, conchas de membros de todas as famílias mencionadas acima foram encontradas em campos agrícolas. No município de Kanju, foram encontradas conchas de membros da família Bradybaenidae e Zonitidae. A partir dessas constatações, concluiu-se que o distrito de Swat possui uma malacofauna significativa que antes era inexplorada e ajudava mais a literatura existente sobre a malacofauna. Também apoia a ideia de que o agroecossistema é rico em diversidade de espécies. Recomenda-se a realização de um estudo mais aprofundado e extenso para uma taxonomia detalhada das famílias de gastrópodes terrestres descritas.(AU)

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Abstract Introduction: The snail Hexaplex princeps is the most important gastropod in the fishery of Guerrero, but capture is not legally regulated for lack of enough studies about its reproduction, growth and other fishing aspects. Objective: To assess fishery data for H. princeps in Guerrero. Methods: From October 2016 to December 2017, we analyzed histological samples of the gonads from 6 to 13 individuals per month. We also collected data on pre-reproductive organisms captured in Costa Chica (2013 and 2014), Costa Grande (2017) and Acapulco (2019 and 2020). Results: Both sexes have five stages of gonadal development; most reproductive activity was from December to July, related to sea surface temperatures of 26 to 28 °C. The LC M in females was 94.1 mm (males: 86.1 mm). There was a high percentage of juvenile organisms in the catches (88.6 %). Conclusions: To let these snails reproduce at least once, we recommend a fishing ban from December to July, and that the minimum size of commercial capture be set at 94.1 mm.

Resumen Introducción: El caracol Hexaplex princeps es el gasterópodo más importante en la pesquería de Guerrero, pero su captura no está regulada legalmente por falta de suficientes estudios sobre su reproducción, crecimiento y otros aspectos de la pesca. Objetivo: Evaluar los datos de pesca de H. princeps en Guerrero. Métodos: De octubre 2016 a diciembre 2017, analizamos muestras histológicas de las gónadas de 6 a 13 individuos por mes. También recolectamos datos sobre organismos pre-reproductivos capturados en Costa Chica (2013 y 2014), Costa Grande (2017) y Acapulco (2019 y 2020). Resultados: Ambos sexos tienen cinco etapas de desarrollo gonadal; la mayor actividad reproductiva fue de diciembre a julio, relacionada con las temperaturas superficiales del mar, que se encuentran entre 26 y 28 °C. El LC M en hembras fue de 94.1 mm (machos: 86.1 mm). Hubo un alto porcentaje de organismos juveniles en las capturas (88.6 %). Conclusiones: Para que estos caracoles se reproduzcan al menos una vez, se recomienda una veda de diciembre a julio y que la talla mínima de captura comercial se fije en 94.1 mm.

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Resumen Introducción: Spiraxidae es la familia de gasterópodos terrestres más diversa de México con una distribución principalmente neotropical. Sin embargo, la influencia de las condiciones ambientales de esta región en su distribución aún es poco conocida. Objetivo: Determinar las afinidades zoogeográficas y la influencia de factores ambientales en la distribución de Spiraxidae en México. Métodos: Compilamos registros de distribución de museos y usamos modelos para establecer áreas con composición de especies, concentración de especies, afinidades y relaciones con variables ambientales similares. Resultados: Encontramos 231 especies y subespecies, 96 en el estado de Veracruz y 74 en la Sierra Madre Oriental. La principal afinidad zoogeográfica fue neotropical. El bosque mesófilo de montaña tuvo la mayor cantidad de especies y subespecies (93). Tres de los grupos zonales tienen una composición particular de especies y el 67 % de las especies son especialistas de hábitat. La presencia de especies sigue un gradiente ambiental, con la cubierta de árboles de hoja perenne de hoja ancha y la precipitación media anual como variables determinantes. Las especies del norte tuvieron mayor tolerancia a la aridez y menor cobertura de hojas. Conclusiones: Spiraxidae tiene su mayor diversidad en los estados del Sur de México; sin embargo, la zona nororiental tiene más registros de especies. Estos caracoles se encuentran principalmente en bosques mesófilos de montaña y bosques tropicales siempre verdes. Las especies del norte de México tuvieron una mayor tolerancia a los sitios con poca lluvia y menos cobertura de árboles de hoja perenne de hoja ancha que las especies del sur.

Abstract Introduction: Spiraxidae is the most diverse family of terrestrial gastropods in Mexico with a mainly neotropical distribution. However, the influence of environmental conditions in this region on its distribution is still poorly known. Objective: To determine zoogeographic affinities and the influence of environmental factors on the distribution of Spiraxidae in Mexico. Methods: We compiled museum distribution records and used models to establish areas with similar species composition, species concentration, affinities and relationship with environmental variables. Results: We found 231 species and subspecies, 96 in Veracruz state and 74 in Sierra Madre Oriental. The main zoogeographic affinity was neotropical. Mountain mesophyll forest had the most species and subspecies (93). Three of zone groups have a particular species composition and 67 % of the species are habitat specialists. Species presence follows an environmental gradient, with broadleaf evergreen tree cover and average annual precipitation as determining variables. Northern species had greater tolerance to aridity and reduced leaf cover. Conclusions: Spiraxidae has its greatest diversity in the Southern states of Mexico; however, the Northeastern zone has more species records. These snails mostly occur in mesophyll mountain forest and tropical evergreen forest. Species from Northern Mexico had greater tolerance to sites with low rainfall and less broadleaf evergreen tree cover than Southern species.

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Malacologists took notice of tree snails in the genus Liguus during the last decades of the nineteenth century. Since then, Liguus have undergone repeated shifts in identity as members of species, states, shell collections, backyard gardens, and engineered wildernesses. To understand what Liguus are, this paper examines snail enthusiasts, collectors, researchers, and conservationists-collectively self-identified as Liggers-in their varied landscapes. I argue that Liguus, both in the scientific imaginary and in the material landscape, mediated knowledge-making processes that circulated among amateur and professional malacologists across the United States and Cuba during the twentieth century. Beginning with an examination of early Liggers' work in Florida and Cuba, this paper demonstrates how notions of taxonomy and biogeography informed later efforts to understand Liguus hybridization and conservation. A heterogeneous community of Liggers has had varied and at times contradictory commitments informed by shifting physical, social, and scientific landscapes. Genealogizing those commitments illuminates the factors underpinning a decision to undertake the until now little-chronicled large-scale and sustained transplantation of every living Floridian form of Liguus fasciatus into Everglades National Park. The social history of Liggers and Liguus fundamentally blurs distinctions between professional scientists and amateur naturalists. The experiences of a diverse cast of Liggers and their Liguus snails historicize the complex character of human-animal relations and speak to the increasing endangerment of many similarly range-restricted invertebrates.

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The Lymnaeidae constitute a family of freshwater gastropod molluscs whose diversity and ecology have been infrequently studied throughout Colombia. Some lymnaeid species act as intermediate hosts of trematode parasites, which are of great importance in both the veterinary and medical fields. Among trematode parasites, Fasciola hepatica is best known for being an important parasite of sheep and cattle for decades and causes significant economic losses in these livestock species. The main objective of this work is to identify the various species of lymnaeids that occupy different geographical regions of Santander and its bordering departments within Colombia. This will expand the knowledge of lymnaeid diversity in Colombia and provide further insight into their role in the transmission of F. hepatica. A total of 118 georeferenced sites between 126 m.a.s.l. and 3870 m.a.s.l. were sampled in Santander, Boyacá, Norte de Santander and Cundinamarca, respectively. Lymnaeid snails were identified according to the morphology of their shells and by several characteristics of their reproductive systems. Species identification was confirmed using DNA barcoding. Four lymnaeid species are reported in the study area: the native Galba cousini and three exotic species, Pseudosuccinea columella, G. truncatula and G. schirazensis. The four species were examined for natural infection with F. hepatica. Infected variants of the main snail host, G. cousini, were found in the Onzaga, Encino and Vetas municipalities of Santander, as well as in the Belén municipality of Boyacá. A second species, G. truncatula was also found naturally infected in Mutiscua municipality of Norte de Santander. The two other species, P. columella and G. schirazensis were found free of infection.

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Introduction: The gastropod Bostryx torallyi shows high variability in shell shape and coloration. Subspecies of this organism have been described based on shell characters but, since they were slightly different, they were synonymized afterwards. Until now, shell variability has been analyzed only descriptively and its anatomy is still unknown. Objective: In this study, I provide anatomical information of B. torallyi and apply a geometric morphometric analysis to evaluate the shell shape variation among specimens. Methods: To accomplish this, type material and numerous lots were examined and dissected out. Additionally, relative warp analysis, based on 9 landmarks in ventral view of the shell, was performed using 80 specimens of 9 localities from Bolivia and Argentina. Results: According to our results, geometric morphometrics is a suitable method to evaluate differences in shell shape among localities; for instance, distinctions in the shell were noticeable between gastropods of low and high altitudes. On the other hand, it was established that the coloration of this species is independent of large-scale factors since the examined specimens came from environments with similar conditions. Furthermore, the sculpture of the protoconch and anatomy of B. torallyi coincided with the other Argentinian species of the genus. Conclusions: Therefore, I concluded that a geometric morphometric analysis of shell shape is a good complement to traditional qualitative description of the characteristics of the shell in this species.

Introducción: El gasterópodo Bostryx torallyi exhibe una gran variabilidad en la forma y coloración de su concha. Subespecies de este organismo han sido descritas con base en los caracteres de la concha; pero, dadas las sutiles diferencias, fueron luego sinonimizadas. Hasta el momento, la variabilidad de la concha ha sido analizada solo descriptivamente y su anatomía es aún desconocida. Objetivo: En este estudio, los objetivos fueron:proveer información anatómica de B. torallyi y usar un análisis de morfometría geométrica para evaluar la variación de la forma de la concha entre especímenes. Métodos: Para ello, se examinó y disectó material tipo y numerosos lotes. Adicionalmente, se realizaron análisis del "relative warp", basados en nueve "landmarks" en vista ventral de la concha, empleando 80 especímenes de nueve localidades de Bolivia y Argentina. Resultados: De acuerdo con los resultados, la morfometría geométrica resultó útil para demostrar diferencias en forma de la concha entre localidades; por ejemplo, se detectarondiferencias evidentes entre localidades de alta y baja altitud. Se determinó que la variación en la coloración de esta especie es independiente de factores a gran escala, dado que los especímenes examinados proceden de ambientes con condiciones similares. Por otro lado, la escultura de la protoconcha y la anatomía de B. torallyi resultaron coincidentes con la de otras especies de este género recolectadas en Argentina. Conclusiones: Se concluyó que el análisis de morfometría geométrica de la forma de la concha fue un buen complemento a la descripción cualitativa tradicional de caracteres de concha.

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Newly arrived species on young or remote islands are likely to encounter less predation and competition than source populations on continental landmasses. The associated ecological release might facilitate divergence and speciation as colonizing lineages fill previously unoccupied niche space. Characterizing the sequence and timing of colonization on islands represents the first step in determining the relative contributions of geographical isolation and ecological factors in lineage diversification. Herein, we use genome-scale data to estimate timing of colonization in Naesiotus snails to the Galápagos islands from mainland South America. We test inter-island patterns of colonization and within-island radiations to understand their contribution to community assembly. Partly contradicting previously published topologies, phylogenetic reconstructions suggest that most Naesiotus species form island-specific clades, with within-island speciation dominating cladogenesis. Galápagos Naesiotus also adhere to the island progression rule, with colonization proceeding from old to young islands and within-island diversification occurring earlier on older islands. Our work provides a framework for evaluating the contribution of colonization and in situ speciation to the diversity of other Galápagos lineages.

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