Despite extensive histology descriptions in fishes, comparable information for the sparrow rasbora (Boraras urophthalmoides), an important freshwater fish in Thailand, remains scarce. This study characterized the histology and histochemistry of the major organ systems in female B. urophthalmoides. Ten healthy adult females collected from freshwater habitats in Nakhon Nayok Province, Thailand, were examined using routine histological and histochemical methods. The results demonstrated the organization of the digestive, reproductive, respiratory, circulatory, nervous, integumentary, and urinary systems. The digestive system showed clear regional differentiation from the oral cavity to the intestine, together with the associated liver and pancreas. The ovary contained oocytes at various developmental stages, each with distinct histochemical features. The gills, heart, brain, spinal cord, integument, and kidney also exhibited well-defined tissue architecture, indicating functional specialization of the major organ systems. These findings provide baseline histological and histochemical information on B. urophthalmoides and contribute to a better understanding of its biology, ecological adaptations, and potential requirements for captive maintenance and aquaculture.

The fundamental organization of fish tissue is crucial to bridge the fields of histopathology and physiology throughout research on biology. This study examines tissue examination of the Siamese dwarf rasbora, Trigonostigma somphongsi (Meinken, 1958), a critically endangered freshwater fish in Thailand. All fish were obtained from the freshwater area in Nakhon Nayok Province, Thailand, and were then processed using the standard histological and histochemical methods. Our observation clearly provides a detailed histological pattern of the major systems. Interestingly, the oral cavity had three distinct regions based on the presence of a taste bud, a mucous secreting cell and a longitudinal fold in the anterior, middle and posterior regions, referring to the digestive function. Moreover, the mature gonads (mature oocytes and spermatozoa) from all fishes indicate the adult stage. It is noted that this is a foundation of reproductive success under a biological life history, which is implicated to protect the area-based conservation during the rainy season. This study uses a histological approach to provide information related to the systematic functional and anatomical phenomenon of T. somphongsi throughout the basic information for the effective area-based conservation.

The objective of this study was to histologically record the ontogenetic changes in the stomach and hepatopancreas of two sesarmid species, Episesarma singaporense and E. versicolor, studied from the zoeal stage 1 to the crab stage. Specimens of ovigerous females were collected from a hatchery site and all stages (zoea 1 to crab) were processed using the morphology and histological method through semithin section. The results of histological analysis of the digestive system were largely organized within the body and showed a complex organization. The distinction between cardiac and pyloric stomachs in both species was unclear in the zoeal 1 and 2 stages but became evident in zoeal stages 3 and 4. All stomach structures in the megalopa and crab stages, especially the well-developed lateral teeth in the cardiac stomach, were clearer than they were in the zoeal stages. The same development was observed in the hepatopancreas that was fully developed by the zoeal 3 stage and became more intricately branched and larger in later stages. This development is an indicator of larval and later feeding activity, which provides information for aquaculture of two sesarmid species.

The assessment of sea cucumber health in Thailand is incomplete, as it has not included Holothuria scabra, a potentially valuable species for aquaculture. In this study, we examined the health status and gonadal development of H. scabra in relation to its size distribution using morphological and histological methods, as well as the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. All sea cucumbers were obtained between July and August 2024 from pond cultures on Koh Yao Noi Island, Phang Nga Province, a coastal area on the Andaman Sea in Thailand. The specimens could be divided into three size classes: Group I (3.5-6.8 cm), Group II (16.5-19.5 cm), and Group III (20.5-23.5 cm). Specimens in Group I were sexually undifferentiated, whereas specimens in Groups II and III were predominantly sexually mature. The histological alteration index and average value of alteration showed a slight frequency of histopathological alterations in intestines, but the TUNEL assay strongly indicated the presence of apoptotic cells in the intestines, more evident in Group I specimens than other groups (p < 0.05).

ABSTRACT The doublespotted queenfish, Scomberoides lysan (Forsskål, 1775), is an economically important coastal teleost with aquaculture potential. Although aspects of growth and reproduction have been investigated, the digestive physiology of this species remains poorly characterized, representing a critical gap for the development of evidence-based aquaculture protocols. This study provides a morphological and histological characterization of the digestive system of female S. lysan (mean total length = 57.0 ± 0.5 cm) obtained from aquaculture ponds. We examined the entire alimentary canal, from the oral cavity to the hindgut, with special attention to gill structures relevant to feeding mechanics. Distinctive morphological features included heterogeneous gill rakers, with elongated, spine-like structures on the first gill arch contrasting with shorter, blunt rakers on subsequent arches, potentially facilitating opportunistic feeding across different prey types. The intestinal coefficient (0.20-0.36; mean = 0.27 ± 0.05) confirmed carnivorous feeding habits. Histologically, the digestive system exhibited the typical four-layer organization (mucosa, submucosa, muscularis, and serosa) throughout, with region-specific specializations. Notably, gastric glands were significantly more abundant in the cardiac region than in the pyloric stomach (p < 0.01), suggesting functional compartmentalization of digestive processes. Specialized mucus-secreting cells were distributed throughout the digestive system, with variable densities among regions. These findings provide foundational insights into the digestive biology of female S. lysan, establishing an anatomical framework for future studies on digestive morphophysiology in emerging aquaculture species.

Oyster health is important for aquaculture productivity and sustainability. In Thailand, the white scar oyster, Crassostrea belcheri, is being promoted for cultivation, yet its health status has not been compared between research breeding and community farming sites. This study evaluated histopathological features, ultrastructure, apoptosis, and defender against apoptotic death 1 (dad1) gene expression in sexually mature C. belcheri collected from these two sites. Gill tissues were examined by histology, transmission electron microscopy, TUNEL assay, and gene expression analysis, while organ condition was assessed using a Health Assessment Index (HAI). The proportion of TUNEL-positive cells in the gills and mantle differed significantly between sites (p < 0.05), with higher levels in oysters from the farming site. In contrast, TUNEL-positive cells in the digestive gland did not differ significantly between sites, although brown cells were observed only in the digestive gland of oysters from the breeding site, suggesting possible physiological stress. To assess the expression level of dad1 in oysters cultured under different conditions, RT-qPCR revealed no significant difference between the two sites. The breeding site also had lower temperature and salinity than the farming site. Overall, these findings suggest that site-specific environmental conditions may influence gill health and stress-related responses in C. belcheri, providing baseline information for oyster health assessment and aquaculture management.

The coffee berry borer (Hypothenemus hampei) is one of the most destructive pests of coffee worldwide, causing severe economic losses. The entomopathogenic fungus Beauveria bassiana has been widely used as a biological control agent; however, detailed histopathological responses of H. hampei to fungal infection remain poorly understood. This study investigated the morpho-histopathological alterations and apoptosis in adult H. hampei following exposure to B. bassiana. Beetles were immersed in a spore suspension (1×10⁹ conidia/mL) and sampled at multiple time points up to 144 h post-exposure. Histological analyses were performed using hematoxylin-eosin, PAS, Masson’s trichrome, and Grocott’s methenamine silver staining. Apoptotic cells were detected using TUNEL assay, and tissue damage was evaluated using the histological alteration index (HAI). Fungal hyphae were detected in the integument and adipose tissue as early as 12 h post-exposure. From 24 to 144 h, progressive fungal proliferation, cuticle thinning, muscle degeneration, adipose tissue degeneration, and gut epithelial erosion were observed. Quantitative analysis revealed a significant increase in fungal area and a marked reduction in cuticle thickness (p < 0.001). Apoptotic cell density increased in a time-dependent manner, with strong immunoreactivity observed after 60 h. These findings demonstrate that B. bassiana rapidly penetrates and disrupts host tissues, leading to extensive structural damage and apoptosis. Understanding the infection dynamics of B. bassiana provides important insights for optimizing biological control strategies and enhancing sustainable pest management in coffee agroecosystems. HIGHLIGHTS First detailed morpho-histopathological analysis ofBeauveria bassiana infection in Hypothenemus hampei. Rapid fungal penetration of the cuticle and adipose tissue were observed within 12 h post-exposure. Significant reduction in cuticle thickness and expansion of fungal area from 48 - 144 h. Time-dependent increase in histological alteration index (HAI) and apoptotic cell density. Findings clarify infection dynamics supporting the biological control development. GRAPHICAL ABSTRACT

There was an error in the original publication regarding several quantitative statements in the Introduction section [...]

Plant resistance to herbivores is a key component of integrated pest management (IPM). Silicon (Si) amendment in rice (Oryza saliva) influences multiple plant defense responses, particularly against phloem-feeding insects like the rusty plum aphid (Hysteroneura setariae). This greenhouse study examined the effects of Si supplementation (calcium silicate, Ca2SiO4) at 0%, 2%, and 4% per gram of soil on silicification and aphid infestation. Defense-related enzyme activities-including peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL)-were measured in aphid-infested rice plants with and without Si amendment. Results showed that Si-treated plants exhibited increased silicification and larger silicon cell size in leaf sheaths than untreated plants. Aphid infestation was significantly lower in plants amended with 2% and 4% Si than in non-amended controls. Additionally, POD, PPO, and PAL activities were higher in Si-treated plants than in non-amended aphid-infested plants. These findings suggest that Si supplementation enhances rice resistance to aphids by inducing plant defense responses, offering a promising strategy for sustainable rice IPM.

Wolbachia are bacterial endosymbionts found widely in arthropods and filarial nematodes. Infecting about half of all arthropod species, Wolbachia manipulate their hosts in various ways, including cytoplasmic incompatibility. Here, we investigated Wolbachia diversity in Bactrocera and Zeugodacus, two prevalent tephritid fruit fly genera, using molecular methods. Wolbachia was only detected in Zeugodacus apicalis (de Meijere) (Diptera: Tephritidae) and not in the other 7 studied species. This newly discovered strain, named wZap, belongs to supergroup B with a 1.3 Mb genome containing 1,248 genes. Phylogenetic analysis of its cytoplasmic incompatibility factor genes cifA and cifB revealed their placement within the Type I clade. Given the presence of cif genes in the wZap genome, further research into their roles in fruit flies could be crucial for developing pest control strategies that exploit CI mechanisms.

Integrated pest management (IPM) techniques employing insect-fungal interactions could utilize “entomopathogenic fungi (EPF)” to control insect pests. This approach has garnered significant attention; however, it has seen limited application in combating the brown planthopper, Nilaparvata lugens, a serious rice pest in Thailand and other countries. The goals of this research were to isolate Cordyceps javanica PSUC001 based on morphological and molecular genetic traits and to evaluate its activity against N. lugens using histological methods. The fungi were isolated from infected moth on Khohong Mountain, Songkhla, Thailand. Live adult specimens were inoculated with the isolated C. javanica and examined morpho-histologically from 0 to 108 h post-inoculation. Molecular genetics analysis computed the identity of C. javanica PSUC001, and the initial degeneration of spermatozoa of N. lugens at 48 h post-inoculation. The necrotic spermatozoa of the sampled insects were observed within 108 h among the prominent fungi formation. After thorough evaluation, our research demonstrated a correlation between C. javanica PSUC001 activity and N. lugens, which could induce spermatozoa histopathological changes to understand the fungal destruction and host physiological reactions, aiming to increase mortality and provide effective pest management solutions.

The marine water-strider Halobates hayanus is prevalent in tropical and subtropical marine habitats. Although the ecology and the morphology of this insect are widely accepted, some histological data remain limited. In this study, we determined new data on the organ histological development for specific performance of H. hayanus, locally collected with respect to its total length (TL) from Libong Island, Thailand. Our observation revealed that the TL of this insect could be divided into three groups: (1) Small, 0.1-0.2 cm; (2) Medium, 0.3-0.4 cm; and (3) Large, 0.5-0.6 cm. Histologically, subsequent microscopic development of eyes, Malphigian tubules, midgut, and gonads of H. hayanus were found in Group (3), 0.5-0.6 cm in TL. Surprisingly, the distinctive structure of pigment cells, with strong pigment granules and crystalline cones, was also found in the 0.5-0.6 cm group. Clear mature testes with the presence of sperms were evident in the 0.1-0.2 cm group, and the sampled females from the 0.5-0.6 cm group had mature ovaries with the presence of the vitellogenic stage. The results obtained from this study expanded the histological data of H. hayanus from natural environments, contributing to further determination of the insect's development stages and physiology.

The rubber tree (Hevea brasiliensis) is an economically important crop in Thailand. Severe defoliation caused by emerging diseases has been reported to substantially reduce rubber yields during the leaf fall phase. The classical disease dispersal patterns of fungi in rubber tree plantations might be derived from weeds in adjacent fields. However, this hypothesis remains untested. Therefore, in this study, we collected and isolated fungi from symptomatic weed samples in rubber tree plantations in Krabi Province in southern Thailand. We found that Parameria sp. were dominant, showing the development of conidiomata on leaves. A total of 25 symptomatic Parameria sp. leaves were collected and tested for their pathogenicity on rubber tree leaves. The tests produced six fungal isolates, WC001, WC002, WL001, WL002, WN001, and WN002, that caused spots on the rubber tree leaves similar to those observed on the weeds. Morphological characterization revealed that fungal isolates WC001 and WC002 were Colletotrichum sp., WL001 and WL002 were Lasiodiplodia sp., and WN001 and WN002 were Neopestalotiopsis sp. Multigene phylogenetic analyses of combined act, gapdh, ITS, and tub2 regions identified WC001 and WC002 as Colletotrichum siamense, while analyses of ITS, tub2, and tef1-α regions identified WL001 and WL002 as Lasiodiplodia brasiliensis and WN001 and WN002 as Neopestalotiopsis cubana. The occurrence of fungal diseases in rubber trees is significantly associated with leafy weeds in and around rubber tree plantations that could constitute reservoirs of fungal pathogens. The strategies used to control weeds have to be further considered in the future.

The use of entomopathogenic fungi (EPF), such as Cordyceps javanica, to reduce insect pest populations is gaining traction since it is an environmentally safe approach that can control many pests at different life stages. Here, we focus on the histopathology of the coffee berry borer, Hypothenemus hampei, infected by C. javanica. Morphological observation revealed that C. javanica conidia germinated within 12 h following inoculation according to light microscopic and ultrastructural levels. The fungus thoroughly penetrated the fat body and muscular tissue between 84 and 120 h post-inoculation. Transmission electron microscopy (TEM) confirmed the hyphal invasion of the cuticle at 12 h post-inoculation, with progressive tissue disruption and organelle degeneration, especially mitochondria and rough endoplasmic reticulum in adipocytes. All organelles were completely degenerated at 96 h post-inoculation. There was evidence of a connection between C. javanica activity and the coffee berry borer that might cause histopathological changes in the host defense against the pathogen, pointing to increased mortality and potential control of coffee berry borer in natural populations. Additionally, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) confirmed that apoptotic cells were slightly increased in the adipose tissue and integument of the coffee berry borer. The ability of C. javanica to fatally infect the coffee berry borer suggests that it could be deployed as a biological control agent in the field.

Metarhizium guizhouense (Clavicipitaceae) is an insect pathogen employed as a mycoinsecticide against many insect pests worldwide. In this study, for the first time in a laboratory setting, the pathogenicity of the M. guizhouense isolate PSUM04 was evaluated against the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae). Following the exposure (1 × 10 9 spores/mL) of H. hampei to M. guizhouense PSUM04, morpho-histopathological changes and numbers of apoptotic cells via the TUNEL (terminal deoxynucleotidyl transferase (TdT), dUTP (deoxyuridine triphosphate) nick-end labelling) assay in H. hampei were evaluated at 12-hour intervals until 144 hours after exposure. The external morphology of H. hampei underwent drastic changes from 24 to 144 hours post-exposure accompanied by the degeneration of integument and adipose tissues. The semi-quantitative analytical score of TUNEL-positive cells showed a slight increase at 12 hours after exposure and a significant increase in TUNEL-positive apoptotic cells at 48 hours after exposure. These results suggest a series of tissue alterations of H. hampei during its process of infection with a strain of M. guizhouense , highlighting the pathogen’s potential as a biological control agent in natural settings.

Background:The tribe Xyleborini comprises over 1,300 species of ambrosia beetles, all of which form mutualistic relationships with fungi. Several beetle species exhibit strong host preferences, particularly within the plant family Fagaceae for genera such as Castanopsis. This study documents the xyleborine beetles associated with Castanopsis inermis in Thailand to improve understanding of their host use and diversity. New information:Twenty species of xyleborine ambrosia beetles were collected from a single fallen Castanopsis inermis tree. Amongst them, twelve species were recorded from C. inermis for the first time. One species, Arixyleborus perbrevis Sittichaya & Smith, sp. nov., is described as new to science, while Cnestus ater (Eggers 1923) is newly recorded from Thailand. Some biological observations on xyleborine ambrosia beetles are also presented.

The brown planthopper (BPH), Nilaparvata lugens (Stål, 1854), is a pest of rice plants worldwide. Cordyceps javanica is a destructive entomopathogenic fungus known to attack leafhoppers or BPHs specifically. Live adult BPH samples were inoculated with isolated C. javanica PSUC002, and their interaction was morpho-histologically examined from 0 to 120 h post-inoculation (pi). We observed that the mortality of BPH continuously increased until 120 h pi (Day 5). Tissue alterations in the host were examined after infection using morphological and histological methods, including the Grocott Methenamine Silver stain test (GMS). Filamentous fungi were first found on the external integument at 12 h pi, and fungal conidia attached to the integument at 24 h pi. However, the initial degeneration of BPHs was identified by histology at 6 h pi especially in the integument and adipose tissue. We identified the degeneration and loss of integument and adipose tissue of infected BPHs at 12 h pi, and their necrosis was completed at 96 h pi. The enzymatic index of the sampled fungi (chitinase and protease) peaked at 7 days of incubation. This study demonstrated that C. javanica PSUC002 is useful to control the BPHs as an eco-friendly practice and will possibly be applied in agriculture.

The seagrass beds at Libong Island, Thailand, are a complex ecological habitat supporting many marine organisms. Unfortunately, the seagrass area is being lost, possibly exerting adverse impacts on aquatic life, but comprehensive aquatic monitoring and assessment efforts are still lacking. In this study, sentinel species were selected from two species groups commonly found in this area, pelagic species (Ambassis nalua and A. vachelli) and benthic species (Amphibalanus amphitrite, and Alpheus sp.). Specimens were collected from healthy and unhealthy seagrass areas around the island from April to June 2021. The health of the specimens was assessed using the histopathological approach together with the histological alteration index (HAI). Some histological alterations were identified that HAl values indicated were significantly more prevalent in the unhealthy seagrass areas (P<0.05). Among the invertebrates, A. amphitrite exhibited melanomacrophage centers while Alpheus sp. exhibited lamellar disorganization in gill and degeneration of hepatopancreatic cells. The two fish species exhibited vacuolar degeneration in the liver that was more pronounced in specimens from the unhealthy seagrass area. However, the HAI values calculated for all samples ranged from 0.1 to 1, indicating normal organs. These results suggest the emergence of environmental alteration in the threatened seagrass habitats at Libong Island, where there is a need to monitor impacts on flora and fauna health in further studies. It is also noted that fishes can be sensitive sentinel species of aquatic ecosystem health.

The structural evidence of tephritids, notably Bactrocera albistrigata, B. dorsalis, B. umbrosa, Zeugodacus cucurbitae, and Z. tau complex were explored using histology. These tephritids' male reproductive organs comprised two testes, ducts with deferent ducts, seminal vesicles, and tubular exocrine glands. The testicular follicle was investigated as a cyst during four stages of spermatogenesis (spermatogonium, spermatocyte, spermatid, and spermatozoa). Similarly, the female reproductive systems of these fruit flies were morphologically identical, with a pair of ovaries containing seven meroistic ovariole types. There was also a spermatheca, two lateral oviducts, a common oviduct, and a genital chamber identified. Tephritids have digestive systems (foregut, midgut, and hindgut), excretory systems (malpighian tubules), neural systems, integumentary systems (cuticle and epidermis), and adipose tissue. These data are not only significant and publicly available, but they can also be used in future studies such as on histopathology, ecotoxicological assays, and phylogenic characteristics.