Zoological Studies最新文献

Among the mechanisms of insecticide resistance, knockdown resistance (kdr), causes alterations in the functioning of the voltage-gated sodium channel (Nav), which is the target site for pyrethroids (PYs) and dichloro diphenyl chloroethane (DDT). In Aedes aegypti, 13 kdr mutations associated with PYs resistance have been identified, with V₄₁₀L, V₁₀₁₆I, V₁₀₁₆G, and F₁₅₃₄C being the most reported mutations in the literature. To assess global and temporal trends in the allelic frequencies of these V₄₁₀L, V₁₀₁₆I/G and F₁₅₃₄C mutations, a PRISMA-guided systematic review was conducted to analyzed their distribution and frequency, incorporating new genotyping data from five southeastern Brazilian populations. Genotyping in these populations was performed using allele-specific PCR (AS-PCR), thereby complementing the findings of the review. The results revealed that, out of a total of 187 studies, the F₁₅₃₄C mutation is the most studied (144 studies) and has the widest geographical distribution (47 countries, 4 continents), followed by the V₄₁₀L, V₁₀₁₆I, and V₁₀₁₆G mutations. In southeast Brazil, resistant alleles were detected both individually and in co-occurrence (e.g., V₄₁₀L + V₁₀₁₆I + F₁₅₃₄C), and were associated with PY resistance. These mutations alter Nav, reducing insecticide binding affinity and leading to high-level resistance-particularly when specific genotypic combinations are present. Their global spread poses a significant threat to A. aegypti control efforts, as PYs remain a cornerstone of public health interventions. Urgent, systematic monitoring of kdr allele frequencies and their synergistic effects is essential to optimize insecticide rotation strategies and prevent operational failures. This calls for coordinated international efforts to develop adaptive control strategies.

Aedes albopictus, a vector of arboviruses of medical and veterinary importance, has undergone a remarkable global expansion over the past five decades. This worldwide study analyzes the phylogeography, invasion routes, and demographic history of this mosquito species, tracing its spread from its native range in Asia to Oceania, Europe, America, and Africa. To this end, genetic datasets with distribution patterns aligned with the species' global spread were identified and extracted from publicly available databases. Phylogeographic analyses were conducted at a global level, invasion scenarios were tested, and the demographic history of populations involved in the spread was reconstructed. The mitochondrial genes COI (n = 3896), ND5 (n = 597), and the complete mitogenome (n = 79) were analyzed, revealing higher genetic diversity within the native range and genetic connectivity across all invaded regions, including the Americas, Africa, Europe, and Asia. All genetic markers indicate that the invasion dynamics followed a panmictic population structure, characterized by random mating and high gene flow among populations. Demographic analyses confirm Asia as the ancestral source population and identify multiple introduction events into Europe, the Americas, and Africa. This invasion pattern, combined with the evidence of panmixia, suggests that anthropogenic factors-particularly global trade-play a pivotal role in shaping the genetic connectivity and dispersal of A. albopictus, underscoring the influence of increasing global commerce on the spread of medically and veterinary-relevant species.

Mount Hamiguitan, a UNESCO World Heritage Site and a biodiversity hotspot in the Philippines, supports diverse and unique ecosystems. This study presents the first comprehensive assessment of land snail diversity across five vegetation types: agro-ecosystem, dipterocarp forest, montane forest, mossy forest, and mossy-pygmy forest. A total of 96 individuals, representing 20 species from 6 families, were recorded. The mossy forest exhibited the highest diversity (1-D = 0.85, H' = 2.03), while the agro-ecosystem and mossy-pygmy forest had lower diversity, attributed to habitat disturbance and extreme environmental conditions. Canonical Correspondence Analysis (CCA) revealed that environmental factors, including leaf litter depth, relative humidity, soil pH, and temperature, influenced land snail distributions. Axis 1 (31.85% constrained inertia) showed a gradient favoring generalist species (Tanychlamys sp.) in disturbed, warmer habitats and specialist species (Hemiplecta sp.) in cooler, humid environments. Axis 2 (30.91%) emphasized humidity and leaf litter depth, associating montane forests and species like Trochomorpha sp. 2 with high moisture conditions. The Bray-Curtis similarity index revealed distinct ecological compositions among vegetation types. The agro-ecosystem formed a separate cluster with low species diversity and specialized communities. The mossy-pygmy forest shared similarities with the mossy forest, both characterized by high humidity and dense vegetation. A strong similarity was observed between the dipterocarp and montane forests, suggesting similar environmental conditions and overlapping species. This study underscores the vital ecological role of the mossy forest as a biodiversity refuge and provides critical data for conservation strategies aimed at preserving Mount Hamiguitan's unique ecosystems. It also advocates for targeted conservation efforts to mitigate human disturbances and enhance ecological resilience in this globally significant hotspot.

In social insects, variations in worker behavior at both individual and group levels allow for rapid responses to environmental changes. The individual and group exploration behaviors of the tropical fire ant Solenopsis geminata were investigated in this study. Here we examined the time individual workers spent exploring four different food items, the types of food they discovered, and the dwell time (the duration spent on each food item). We also examined whether individual variations in exploratory behavior influence group-level exploratory behavior. In the individual exploration assay, there were significant effects of nest and food on the dwell time. The average exploratory time taken by workers in the group exploration assay showed no significant difference between experienced and inexperienced workers in Nest 1. However, a significant difference was found between the groups in Nest 2. Here, observations showed that S. geminata workers in the group could find the food more quickly than individual workers. Our work suggested that varying degrees of exploratory behavior exist among individual workers and groups, which may potentially impact foraging efficiency and resource utilization. The tropical fire ant, S. geminata, is a globally invasive species that has been introduced to Taiwan for over 40 years. Incorporating an analysis of exploratory behavior into the study of invasive species allows us to better understand the mechanisms driving their progression.

The increasing global introduction of alien species in recent decades underscores the need to understand the factors driving their establishment and spread in order to mitigate their ecological impacts. As alien species often thrive due to the absence of natural enemies (e.g., parasites), we investigated leech parasitism in freshwater turtles, focusing on an assemblage with over 10 years of co-occurrence between native species (Phrynops geoffroanus, Hydromedusa tectifera) and invasive sliders (Trachemys dorbigni, Trachemys scripta elegans). We used traps to capture 62 turtles to assess host characteristics (species, sex, body size, and body region) that influence leech prevalence and infestation intensity in southern Brazil. Our findings revealed that native turtles exhibited an 18-fold higher prevalence of hematophagous leech than invasive species, with T. dorbigni being the only species in which no leech infestation was observed. Infestation intensity also varied among species, with native turtles harboring more leeches. Probability of leech infestation increased with body size, and the hind limbs were significantly more infested. The diminished presence of ectoparasites on invasive Trachemys throughout this coexistence period supports the enemy release hypothesis, suggesting that the lack of natural enemies may be a potential driver facilitating their invasion success. These results provide baseline data for future studies exploring key factors in the success of the slider invasions.

The present study describes and illustrates the morphology of naupliar and copepodid stages of Caligus sclerotinosus Roubal, Armitage and Rohde, 1983 (Copepoda: Siphonostomatoida: Caligoida), an invasive, non-indigenous parasite collected from commercially important red sea bream Pagrus major (Temminck and Schlegel, 1843) (Sparidae) cultured as well as wild populations in western Japan. The life cycle of C. sclerotinosus consists of 8 stages: two nauplii, five copepodids (copepodid I to V) and one adult, which exhibited the general pattern of other congeners. Sexual dimorphism was first observed in the urosome and antenna of copepodid IV. The body lengths of the developmental stages of 14 Caligus spp. are compared to those of C. sclerotinosus. The oral cone of copepodid I is highly unique for its suckerlike shape, widely expanded terminally. All post-naupliar stages were found on the same host fish P. major, rejecting the previous hypothesis for the presence of intermediate hosts for the development of C. sclerotinosus.

Bark and ambrosia beetles are major pests in fruit tree orchards worldwide. In this study, we aimed to investigate bark and ambrosia beetle communities present in apple orchards in East Java, Indonesia. We sampled bark and ambrosia beetle communities using ethanol-baited traps in two different cropping systems, i.e., polyculture and monoculture. We collected 353 individuals representing four tribes, 13 genera, and 16 species of both beetles. The most abundant species was Xylosandrus morigerus (Blanford), indicating that this species may be well established in apple orchards. Bark and ambrosia beetle abundance and species richness in apple orchards were higher in the polyculture cropping system. Nevertheless, apple orchards surrounded by a high number of forest patches (in a radius of one kilometer) were more at risk of being invaded by bark and ambrosia beetles than those surrounded by a lower number of forest patches. Continued monitoring of bark and ambrosia beetles on apple orchards could play a significant role in the early detection and the development of proactive measures for sustainable pest management.

This study presents a comprehensive examination of a recently identified intertidal limpet species, Patelloida parva n. sp., utilizing a multidisciplinary approach that combines molecular analyses and detailed morphological investigations. Molecular analysis, involving mitochondrial (16S rRNA) and recently reported single nucleotide polymorphism markers, has been instrumental in distinguishing Patelloida parva n. sp. from its congeners. In addition to genetic divergence, this study provides a description of both morphology and species distribution, revealing key features that set Patelloida parva n. sp. apart from closely related Patelloida species found in Japan. Patelloida parva n. sp. is mainly distributed in the upper intertidal of the Pacific coasts of Wakayama and Kochi Prefectures, Japan, but morphological analysis suggests that there are also populations on the Ryukyu Islands. Furthermore, this study hypothesizes the tropical origin of Patelloida parva n. sp., attributing its distribution pattern to the influence of the Kuroshio Current. Genetic analyses indicate a closer sequence divergence (5%) to the tropical P. saccharinoides compared to the P. lanx (11%) co-occurring in intertidal rocky shores. This study not only contributes to the understanding of the species' ecology but also underscores the importance of considering both genetic and morphological aspects in the taxonomy of limpets within Patelloida.

This inventory provides a comprehensive list of 286 agriculturally important insect species from cruciferous crops (bok choy, broccoli, brussels sprouts, cabbage, cauliflower, kale, mustard, radish, rapeseed, and toria), spanning 10 orders: Coleoptera, Dermaptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, Neuroptera, Odonata, Orthoptera, and Thysanoptera. These species belong to 53 families, with Coccinellidae comprising the most species (39), followed by Syrphidae (22) and Apidae (20). Functional diversity analysis highlights that foliage feeders dominate the pest category (52%), while nymphaladult predators make up the majority of natural enemies (45%). Larval parasitoids and pupal parasitoids account for 27% and 10%, respectively. Hymenoptera (51%) leads among pollinators, followed by Lepidoptera (21%) and Diptera (17%). This first-of-its-kind inventory serves as a valuable resource for field entomologists and other stakeholders in pest management and conservation strategies.

Symbiotic relationships between polychaetes and marine invertebrates are well-documented, with echinoderms-primary starfish and sea cucumbers-as common hosts and sea urchins being more rarely involved. Although many sea urchins possess venomous spines that are effective defenses and make them suitable hosts for symbionts, the dense packing of these spines difficult hosting symbiotic polychaetes. In this study, we describe two new genera and species of polynoid polychaetes found in association with two different species of sea urchins, collected through dredging from Sagami Bay, Japan. Echinophilia gen. nov. is characterized by an elongated body, 12 pairs of elytra, subdistally inflated antennae and dorsal cirri. Paraechinophilia gen. nov., in contrast, has a non-elongated body, 12 pairs of elytra, not inflated antennae and dorsal cirri. Additionally, we provide insights into their phylogenetic relationships based on four gene sequences (COI, 16S, 18S, and 28S).