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Diversity and above-ground height of vascular epiphytes in a seasonally dry tropical forest on a white sand hill in Ankarafantsika National Park, northwestern Madagascar
No full textThis study presents a comprehensive checklist of vascular epiphytes in a forest of Madagascar and documents their forest stand scale distribution for the first time. Fourteen species belonging to 11 genera in four families were recorded from 30.6 ha of seasonally dry tropical forest in the Ankarafantsika National Park in northwestern Madagascar. Most epiphytes were found in the lower to middle strata of the forest. Epiphytes were recorded on 26 host plant species (phorophytes) belonging to 20 families of trees, shrubs, or lianas. Among the epiphytes, Orchidaceae had the highest species richness (79% of the total recorded species), whereas the other three families, Acanthaceae, Basellaceae, and Moraceae, have one species each (7%). Obligate epiphytes, accidental epiphytes, and hemiepiphytes were identified, constituting 57% (Orchi‑ daceae), 28% (Orchidaceae, Acanthaceae, and Basellaceae), and 7% (Moraceae), respectively. Two species, Microcoelia physophora (Rchb.f.) Summerh. (Orchidaceae) and Basella madagascariensis Boivin ex H.Perrier (Basellaceae), are newly recorded in the park and in the Boeny region, respectivel
Reducing Memory and Computational Cost for Deep Neural Network Training with Quantized Parameter Updates
No full textFor embedded devices, both memory and computational efficiency are essential due to their constrained resources. However, neural network training remains both computation and memory intensive. Although many existing studies apply quantization schemes to mitigate memory overhead, they often employ stochastic rounding for both inference and gradient computation. Notably, no prior work has explored its advantages exclusively in parameter updates. Here, we in-troduce Quantized Parameter Updates (QPU), which uses stochastic rounding (SQPU) to achieve improved and more stable training outcomes. Our fixed-point quantization scheme quantizes parameters (weights and biases) upon model initialization, conducts high-precision gradient com-putations during training, and applies stochastically quantized updates thereafter. This approach substantially lowers memory usage and enables mostly quantized inference, thereby accelerating calculations. Furthermore, storing quantized inputs for gradient computation reduces memory demands even more. When tested on the FASHION-MNIST dataset, our method matches the Straight-Through Estimator (STE) in performance, delivering 0.92% validation accuracy while consuming just 57% of the memory during training. Accepting a slight 1.5% drop in accuracy yields a 50% memory reduction. Additional techniques include stochastic rounding in inference, the use of higher precision for parameters than for layer outputs to limit overflow, L2 regularization via weight decay, and adaptive learning-rate scheduling for improved optimization across a range of batch sizes
Acoustic Monitoring of Invasive Species: Continental Patterns in Calling Activity of the Invasive Cane Toad
No full textInvasive populations are managed most effectively when surveillance targets periods and places of maximal activity or detectability. Understanding the factors influencing breeding of invasive species is also important for modelling population growth and spread. Despite their continued successful advances, the patterns and drivers of invasive cane toad (Rhinella marina) calling activity remain poorly resolved at broad scales in Australia. Using continent-wide passive acoustic recording data paired with a machine-learning acoustic classifier, we describe patterns in when, where, and under what conditions cane toad choruses begin and persist across most of their current range in Australia, spanning three states and climate zones (~15° latitude and 27° longitude). A total of 163,701 minutes of cane toad calls from 33,799 nights of recordings showed that they chorused near year-round, with seasonal peaks. Cane-toad calling probability and intensity increased on dark, calm, humid nights, and near lentic systems or temporary water, and with low- to medium canopy cover, and decreased with increasing wind and moonlight. Social cues were important: prior-week calling activity strongly elevated both probability and intensity of calling. Interestingly, temperature effects were context-dependent, without a prior chorus, calling probability and intensity peaked at moderate temperatures; following chorusing, both metrics remained high across a broader thermal range. However, variable importance differed among climate zones: atmospheric and lunar factors were more influential for initiating choruses in subtropical and semi-arid sites, whereas habitat and hydrology contributed more to sustaining choruses in the tropics. Together, these results reveal a detailed picture of cane toad calling ecology in Australia, identifying when, where, and under what conditions chorusing is favoured. This study not only demonstrates the use of ecoacoustics for effective monitoring and understanding of vocal invasive species, but also supplies a comprehensive, data-driven foundation for predictive models and future real-time monitoring that can allow targeted management for this global invader
Dive into the Italian PONDY dataset: Pond vegetation data and water physico-chemical parameters
No full textPonds are widespread yet highly vulnerable freshwater habitats that support diverse aquatic and terrestrial plant communities influenced by land use and water characteristics. The PONDY (Pond vegetation data and water physico-chemical parameters) dataset integrates vegetation and water physico-chemical data that have been collected to understand the responses of vegetation to environmental parameters. The dataset comprises 575 plots, of which 232 are aquatic and 343 are terrestrial, derived from 115 ponds across continental and insular areas of Italy. The dataset includes 743 vascular plant taxa and 5 macroalgae encompassing 364 genera and 89 families. Terrestrial plots host 690 taxa belonging to 87 families, while aquatic plots host 117 taxa belonging to 36 families. The dataset includes 10 taxa belonging to the Italian Red List and 39 alien species. Moreover, 11% of the aquatic plots have been classified in a Habitats Directive 92/43/EEC habitat type, while 48% have been classified in a EUNIS habitat type. The dataset contains, for each plot, measurements of physico-chemical water variables such as dissolved oxygen, water depth, and temperature, pH, turbidity, conductivity, and nutrient concentration. The PONDY dataset provides comprehensive information on plant diversity and abundance, community composition, habitat types, and water chemistry in Italian ponds, serving as a key resource for studying plant–environment relationships, developing predictive models, and supporting freshwater conservation efforts
First records of Hippasosa ghost (Jocque & Jocqué, 2017) (Araneae, Lycosidae) outside of the type locality in northwestern Madagascar
No full textThe Malagasy endemic wolf spider Hippasosa ghost (Jocque & Jocqué, 2017), previously known from a single small patch of sandy habitat adjacent to a permanent lake in the Mariarano Classified Forest in northwestern Madagascar, is recorded from two additional localities with similar habitat along the Mariarano River, 10 km and 45 km from the type locality. These finds indicate the possibility that this highly specialized species could have a larger distribution than originally thought, but also they show the importance of protecting such vulnerable habitats
A new species record of Hemiphyllodactylus lungcuensis Luu, Nguyen, Do, Pham, Hoang, Nguyen, Le, Ziegler, Grismer & Grismer, 2023 (Squamata, Gekkonidae) from Yunnan Province in China
No full textHemiphyllodactylus lungcuensis Luu, Nguyen, Do, Pham, Hoang, Nguyen, Le, Ziegler, Grismer & Grismer was described in 2023, based on seven specimens. Its type locality is Lung Cu Commune, Dong Van District, Ha Giang Province, in north-eastern Vietnam, near the Sino-Vietnamese border. Currently, the species is known only from the type locality; there are no records of its occurrence in China.On 10 August 2025, we collected a single Hemiphyllodactylus specimen in Lida Town, Funing County, Yunnan Province, China. In the phylogenetic tree, this individual clusters with the paratypes and holotype of H. lungcuensis with strong support. The specimen from China agrees well with the original morphological description of the species and has a minor mean genetic distance of 1.9% in the ND2 gene with the type specimen of this species. Here, we report the first record of H. lungcuensis for China
Taxonomic position of the fossil ant genus Stiphromyrmex Wheeler (Hymenoptera: Formicidae), with the first description of its queen
No full textThe previously unknown queen of Stiphromyrmex robustus (Mayr, 1868) is described. The taxonomic position of the fossil genera Stiphromyrmex Wheeler, 1915, Enneamerus Mayr, 1868, and Thanacomyrmex Chény, Wang & Perrichot, 2019 is discussed, and their placement in the Myrmecina genus-group of the tribe Crematogastrini Forel, 1893 is confirmed. A key for the identification of fossil genera and species of this genus-group is provided
Effect of tooth hypersensitivity and caries risk on enamel electrical resistance values
No full textAbstract Introduction: Tooth enamel has a high specific electrical resistance due to its mineral-rich composition. The decreased electrical resistance is associated with the low mineral content of the enamel tissue and can be used as a method for early diagnosis of incipient caries. This indicates compromised enamel protection in the absence of clinically evident enamel damage, permitting reactions to irritants without direct dentin exposure. Aim: The study aims to investigate the relationship between reduced enamel electrical resistance measured using the CarieScanPro device and the presence of tooth hypersensitivity and varying levels of caries risk. Materials and methods: The study involved a total of 60 patients ranging in age from 25 to 45 years, who were categorized into two distinct groups based on their caries risk and the presence or absence of tooth hypersensitivity. The risk of developing dental caries was assessed using an American Dental Association (ADA) questionnaire. This questionnaire was translated and validated in Bulgarian. A total of twenty teeth were examined for each patient, with the teeth being categorized into four groups based on their location within the oral cavity: the first group consisted of the upper central incisors, the second group consisted of the upper lateral incisors, the third group consisted of the lower central incisors, and the fourth group consisted of the lower lateral incisors. The electrical resistance of the enamel on the vestibular cervical surface was measured on each tooth. To this end, a CarieScanPro device was utilized, which shows the result as both a numerical value and a letter on a display. Results: A statistically significant difference in the value of electrical resistance was found between patients with and without tooth hypersensitivity, but there is no such difference in patients with different degrees of caries risk. Conclusions: Tooth hypersensitivity is significantly associated with a higher prevalence of teeth with reduced electrical resistance, regardless of caries risk level
Phylogeny and Taxonomic Revision of Pseudodiploospora (Hypocreales, Pseudodiploosporeaceae) Associated with White Mold Disease of Cultivated Morels in China
No full textWhite mold disease (WMD) is one of the most destructive diseases affecting cultivated morels (Morchella spp.) in China, yet the taxonomy and diversity of its associated pathogens remain poorly resolved. During targeted surveys of WMD from major morel-growing regions in 2023–2024, we obtained 518 isolates belonging to the genus Pseudodiploospora. Although these isolates had historically been treated as a single species, P. longispora, marked morphological variation and preliminary phylogenetic signals indicated the presence of a species complex. To reassess species boundaries, we employed multilocus phylogenetic analyses integrated with coalescent-based species delimitation and detailed morphological examination. Five distinct species were resolved, comprising P. longispora and four novel taxa: P. aequatospora, P. crassispora, P. curvispora, and P. tenuispora. Our results also support a taxonomic revision of Pseudodiploospora, refining generic limits and improving nomenclatural stability. This study provides the first comprehensive assessment of species diversity within Pseudodiploospora associated with WMD and establishes a robust taxonomic framework for future ecological and pathogenicity research
Geographical patterns in the distribution of naturalized plants in Central America
No full textNon-native plant species are on the rise globally, yet the distribution patterns and environmental drivers in biodiversity-rich regions such as Central America remain poorly understood. These species are affecting biodiversity, ecosystem integrity, and conservation efforts, especially when they become invasive. We analyzed the spatial distribution of 751 naturalized plant species using more than 42,000 records collected through the Global Biodiversity Information Facility (GBIF) across the seven countries in Central America. We evaluated the influence of environmental variables, human population density, protected areas, and life zones on both occurrence and species richness. Human population density appeared as the strongest predictor of naturalized species occurrence and richness, highlighting the role of human activity in promoting invasions. The annual mean temperature and biodiversity integrity were negatively associated with the occurrence and species richness. Tropical rainforests and other humid life zones have more naturalized species than expected by chance. Protected areas had fewer naturalized species overall, but a higher species: observation ratio, showing both conservation value and vulnerability. Naturalized rare species, in terms of the number of records, were found outside protected zones, particularly in disturbed and urbanized areas. Our findings highlight the need for early detection, targeted management, and strengthened protection strategies, especially in mid-elevation zones and densely populated areas. By identifying key environmental and anthropogenic drivers and the most affected regions, this study offers actionable insights for conservation planning and invasive species management in one of the world’s most biodiverse and socio-environmentally vulnerable regions