Use of different dry materials to control the moisture in a black soldier fly (Hermetia illucens) rearing substrate.

Background: Controlling the substrate moisture is a significant challenge in black soldier fly (BSF) farming. Many substrates have a high moisture content, which results in a low BSF biomass and a high mortality. One potential solution involves incorporating dry substrates into the food mix to mitigate the excessive moisture. However, little information about the types and quantities of dry substrates is available. Methods: Six different dry materials-rice husk (RH), rice bran (RB), rice husk ash (RHA), coconut coir dust (CC), rubberwood sawdust (RSD), and spent coffee grounds (SCGs)-were evaluated by combining with pure minced mixed vegetables in varying proportions (0%, 5%, 10%, 15%, 25%, and 50% by weight). This study encompassed both small-scale and medium-scale experiments to comprehensively assess the effects of the addition of each of these different dry substrates and their quantities on aspects of the development of BSF, such as BSF biomass, larval duration, mortality rates, adult sex ratio, and the moisture removal efficiency of each substrate mixture. Results: Each dry substrate had specific properties. Although RB emerged as a favorable dry substrate owing to its nutritional content and substantial water-holding capacity, excessive use of RB (>15% by weight) resulted in elevated temperatures and subsequent desiccation of the substrate, potentially leading to larval mortality. In contrast, RH demonstrated the ability to support improved larval duration and growth, permitting its utilization in higher proportions (up to 50%). On the other hand, CC, RHA, and SCG are better suited for inclusion in BSF larval substrates in smaller quantities. Discussion: Some dry substrates require a pretreatment process to eliminate toxic substances prior to their incorporation into substrate mixtures, such as CC and SCG. A potential alternative solution involves employing a combination of various dry substrates. This approach aims to enhance the substrate moisture control and subsequently improve the BSF rearing performance.

Tabanus chrysurus is a potential biological vector of Trypanosoma (Megatrypanum) theileri in Japan.

Several species of horse flies (Diptera: Tabanidae) are known as vectors of Trypanosoma (Megatrypanum) theileri and T. theileri-like trypanosomes; these host-parasite relationships were established based on the developmental stages of these parasites discovered in the hindgut of horse flies. T. theileri and T. theileri-like trypanosomes have been detected in cattle and wild deer in Japan; however, the vector horse fly species remains unidentified. Therefore, in this study, we aimed to identify the potential horse fly species serving as vectors of T. theileri in Japan. A total of 176 horse flies were collected between June to September 2020 and 2021 in Tokachi, Hokkaido, Japan. The T. theileri infection in the captured horse flies was determined by PCR and microscopic analyses of their midgut and hindgut. Additionally, the trypanosome, microscopically detected in a horse fly, was molecularly characterized and phylogenetically analyzed using 18S rRNA and partial cathepsin L-like protein gene (CATL) sequence of the trypanosome. The microscopy and PCR analyses revealed 0.57% and 35.8% prevalence of T. theileri in horse flies, respectively. Epimastigote stages of T. theileri, adhered to the hindgut epithelial cells of Tabanus chrysurus via flagella or actively moving in the lumen of the gut, were detected. Phylogenetic analysis revealed the connection of isolated trypanosomes with T. theileri in the TthI clade. These results suggest that Ta. chrysurus is a potential vector of T. theileri.

First record of Psorophora ferox (Diptera: Culicidae) infested with eggs of Dermatobia hominis (Diptera: Cuterebridae), in Ucayali: Peru.

INTRODUCTION: Dermatobia hominis belongs to the Cuterebridae family, Diptera order; These flies inhabit tropical regions where they are called "fly of death" since the larvae are capable of causing lesions in domestic animals, wild animals including humans, the adult females of D. hominis capture other dipteran to oviposit their eggs on them (phoresis), when hematophagous mosquitoes land on an animal and / or human in order to feed on their blood, the eggs hatch and the larvae immediately penetrate the skin where they will develop to later abandon the host, then in the soil and / or other moist substrate the pupal stage develops, finally new adult flies will emerge from the pupae. OBJECTIVE: The primary goal of the present study was to determine as first record, the presence of Psorophora ferox infested with eggs of Dermatobia hominis, Peru. METHODOLOGY: The present study was carried out in an area of the private reserve "El Vencedor", located within the city of Pucallpa, Ucayali Region-Perú. The area is characterized by being humid tropical, with an average temperature of 26ºC and humidity of 92%, while the annual precipitation is approximately 1570 mm3. The capture method was carried out with the help of a hand net type "butterfly" or also called Jama. RESULTS: A total of 668 mosquitoes of different species were collected, the most abundant being Psorophora albigenu and Psorophora ferox, which represented 88.72% and the least abundant was Culex coronator and Uranotaenia apicalis with 0.15% of the total sample collected. CONCLUSIONS: Within these specimens it was captured a mosquito of the species Ps. ferox with the presence of 8 eggs of D. hominis, of which 3 would have hatched, while in the remaining 5, the larvae would remain inside the eggs.

Prevalence and seasonal aspects of parasitism by Oestrus ovis (Diptera: Oestridae) in sheep from Mato Grosso State, Brazil.

Oestrus ovis larvae are obligate parasites of vertebrates and cause cavitary myiasis (oestrosis) in sheep and goats. It is also reported as a zoonosis causing ophthalmomyiasis and nasopharyngeal myiasis. Despite being relatively common in Brazil, epidemiological studies on O. ovis are scarce. Considering that the infestation is influenced by the climate and biomes of the studied region, we aimed to investigate the seasonal prevalence of O. ovis among slaughtered sheep in the northern region of the state of Mato Grosso, Brazil. The heads of sheep (n=697) slaughtered at a slaughterhouse in the municipality of Terra Nova do Norte (November 2011 to November 2013) were collected to count, catalog, and identify the larvae found in the upper respiratory tract. Overall, 45.77% (319/697) of the animals were infested with 2,412 recovered larvae, 96.89% (2,337/2,412) of which were identified at the species level as O. ovis. Seasonal variations in prevalence ranged from 41% (spring) to 56% (summer); however, no correlation was observed between prevalence and season, mean humidity, or temperature. In conclusion, parasitism by O. ovis in sheep in the studied area, occurs year-round, considering the occurrence of larvae (L1, L2, and L3) throughout the year, probably because of the area's environmental conditions.

Artificial light at night bans Chaoborus from vital epilimnetic waters.

Artificial light at night (ALAN) is known to affect organisms in terrestrial ecosystems and adjacent litoral habitats. In the present study, we tested the effect of ALAN on the spatial distribution of organisms in open waters, using the insect larvae of Chaoborus flavicans as an example. During the day C. flavicans typically hide from visually hunting fish in deep, dark, anoxic waters. On safer nights, they forage in rich subsurface waters. Nighttime field tests revealed that light from an HPS street lamp mounted on a boat anchored in open water attracted planktivorous fish, but deterred planktonic Chaoborus from rich but risky surface waters. Chaoborus did not descend to the safest, anoxic hypolimnion, but remained in hypoxic mid-depth metalimnion, which does not appear to be a perfect refuge. Neither light gradient nor food distribution fully explained their mid-depth residence under ALAN conditions. A further laboratory test revealed a limited tolerance of C. flavicans to anoxia. Half of the test larvae died after 38 h at 9 °C in anoxic conditions. The trade-off between predation risk and oxygen demand may explain why Chaoborus did not hide in deep anoxic waters, but remained in the riskier metalimnion with residual oxygen under ALAN conditions.

Relationship of black soldier fly larvae (BSFL) gut microbiota and bioconversion efficiency with properties of substrates.

Treating food waste using black soldier fly larvae (BSFL) is widely regarded as a promising nature-based measure. This study explored the influence of food waste particle sizes on substrate properties and its subsequent effects on bioconversion efficiency and gut microbiota. The results indicated that particle sizes mainly ranging from 4 mm to 10 mm (T1) significantly increased the weight loss rate of food waste by 35 % and larval biomass by 38 % compared to those in T4 (particle sizes mostly less than 2 mm) and promoted the bioconversion of carbon and nitrogen into larvae and gases. Investigation of substrates properties indicated that the final pH value of T1 was 7.79 ± 0.10, with Anaerococcus as the predominant substrate microorganism (relative abundance: 57.4 %), while T4 exhibited a final pH value of 5.71 ± 0.24, with Lactobacillus as the dominant microorganism (relative abundance: 95.2 %). Correlation analysis between substrate chemical properties and microbial community structure unveiled a strong relationship between substrate pH and the relative abundance of Anaerococcus and Lactobacillus. Furthermore, beneficial microorganisms such as Lactobacillus and Enterococcus colonized the BSFL gut of T1, while pathogenic bacterium Morganella, detrimental to BSFL gut function, was enriched in T4 (relative abundance: 60.9 %). Nevertheless, PCA analysis indicated that alterations in the gut microbial community structure may not be attributed to the substrate microorganisms. This study establishes particle size as a crucial parameter for BSFL bioconversion and advances understanding of the relationship between gut microbiota and substrate microbiota.

Succession of medico-legal important flesh flies (Diptera: Sarcophagidae) in the temporal gradient of pig decomposition in the Brazilian Cerrado.

Flies belonging to the Sarcophagidae family play a significant role in forensic investigations by aiding in the estimation of post-mortem interval through the assessment of the developmental time of their immature stages and/or the succession patterns of species on carcasses and cadavers. In this regard, this study aimed to investigate the ecological succession of these flies on pig carcasses within Cerrado of Brazil. The progression of fly succession was examined over a 10-day period using the Threshold Indicator Taxa Analysis (TITAN) approach. Six Z + species (Oxysarcodexia thornax (Walker), Peckia (Sarcodexia) lambens (Wiedemann), Peckia (Euboettcheria) collusor (Curran & Walley), Ravinia belforti (Prado & Fonseca), Tricharaea (Sarcophagula) canuta (Wulp) and Tricharaea (Sarcophagula) occidua (Fabricius)) were identified, with change points ranging from 2.5 to 3 days during the dry season and 2.5 to 5.5 days during the rainy season. Two Z- species (Dexosarcophaga carvalhoi (Lopes) and Peckia (Sarcodexia) tridentata (Hall)) were present, with a change point of 6.5 days during the rainy season. This study provides a continuous analysis of the temporal succession of flies, enabling an investigation into species progression based on their change points and directions (Z + and Z- ), thereby offering methodological advancements to avoid the arbitrary categorization of inherently continuous data.

Using weather data to predict the presence of Lucilia spp. on sheep farms in New Zealand.

Flystrike remains an important animal health issue on New Zealand sheep farms. To date no useful predictive tool to assist farmers to develop control options has been available. The aim of this study was to use National Institute of Water and Atmospheric Research (NIWA) virtual climate station data in New Zealand to develop a weather-based model to accurately predict the presence of Lucilia spp. on sheep farms throughout New Zealand. Three LuciTrap® baited fly traps were positioned on each of eight sheep farms throughout New Zealand (5 in the North Island and 3 in the South Island). The traps were put out for both the 2018-2019 and 2019-2020 seasons. They were emptied each week and the flies morphologically identified; with the counts of Lucilia cuprina and L. sericata combined as Lucilia spp. The count data for Lucilia spp. for each week of trapping was transformed into a binary outcome and a generalised linear mixed effects models fitted to the data, with farm as a random effect. The dependent variable was Lucilia spp. flies caught, yes or no, and the independent variables were mean weekly climate variables from the nearest NIWA virtual climate station to that farm. The model was trained on the 2018-2019 catch data and tested on the 2019-2020 catch data. A cut point was identified which maximised the model's ability to correctly predict whether Lucilia spp. were present or not for the 2019-2020 catch data, and the sensitivity, specificity, accuracy, and area under the curve (AUC) of the model calculated. The final model included just 3 significant variables, mean weekly 10 cm soil temperature, mean weekly soil moisture index, and mean weekly wind speed at 10 m. Mean weekly 10 cm soil temperature accounted for 64.7% of the variance explained by the model, mean weekly soil moisture index 34.7% and mean weekly wind speed at 10 m only 0.6%. The results showed that the predictive model had a sensitivity of 0.93 (95% CI = 0.80-0.98) and a specificity of 0.75 (95% CI = 0.62-0.85), using a cut point for the probability of Lucilia spp. being present on farm = 0.383. This model provides New Zealand farmers with a tool which will allow them to know when Lucilia spp. flies will likely be present and thus more accurately plan their interventions to prevent flystrike.

First report of the morphological and molecular characterization of Pseudolynchia canariensis (Diptera: Hippoboscidae) from Al-Baha region, Saudi Arabia.

This study aims to study the morphological and molecular characterization of (Pseudolynchia canariensis; Macquart, 1839)in the Al-Baha region of Saudi Arabia. Ninety-four pigeons were obtained from traditional pigeon breeding farms of the Al-Baha region, and fly samples were collected. Taxonomic keys were used to define the morphology of flies, whereas molecular characteristics were identified based on cytochrome c oxidase subunit 1. The rate of Pseudolynchia canariensis infestation in the examined pigeons was 44.5%. The genetic sequences of the fly samples were deposited in GenBank (accession number OQ073507). The match rate between the fly samples from the present study and those previously recorded in GenBank (accession numbers: EF531220, OM073981, and MW853922) displayed 99.66%. This study demonstrates that Pseudolynchia canariensis is common in the Al-Baha region; thus, further studies are required to detect other species from the same genus and their geographical distribution.

An alternative peptone preparation using Hermetia illucens (Black soldier fly) hydrolysis: process optimization and performance evaluation.

Background: Hermetia illucens (HI), commonly known as the black soldier fly, has been recognized for its prowess in resource utilization and environmental protection because of its ability to transform organic waste into animal feed for livestock, poultry, and aquaculture. However, the potential of the black soldier fly's high protein content for more than cheap feedstock is still largely unexplored. Methods: This study innovatively explores the potential of H. illucens larvae (HIL) protein as a peptone substitute for microbial culture media. Four commercial proteases (alkaline protease, trypsin, trypsase, and papain) were explored to hydrolyze the defatted HIL, and the experimental conditions were optimized via response surface methodology experimental design. The hydrolysate of the defatted HIL was subsequently vacuum freeze-dried and deployed as a growth medium for three bacterial strains (Staphylococcus aureus, Bacillus subtilis, and Escherichia coli) to determine the growth kinetics between the HIL peptone and commercial peptone. Results: The optimal conditions were 1.70% w/w complex enzyme (alkaline protease: trypsin at 1:1 ratio) at pH 7.0 and 54 °C for a duration of 4 h. Under these conditions, the hydrolysis of defatted HIL yielded 19.25% ±0.49%. A growth kinetic analysis showed no significant difference in growth parameters (µmax, Xmax, and λ) between the HIL peptone and commercial peptone, demonstrating that the HIL hydrolysate could serve as an effective, low-cost alternative to commercial peptone. This study introduces an innovative approach to HIL protein resource utilization, broadening its application beyond its current use in animal feed.

Dynamic expression of cathepsin L in the black soldier fly (Hermetia illucens) gut during Escherichia coli challenge.

The black soldier fly (BSF), Hermetia illucens, has the potential to serve as a valuable resource for waste bioconversion due to the ability of the larvae to thrive in a microbial-rich environment. Being an ecological decomposer, the survival of BSF larvae (BSFL) relies on developing an efficient defense system. Cathepsin L (CTSL) is a cysteine protease that plays roles in physiological and pathological processes. In this study, the full-length of CTSL was obtained from BSF. The 1,020-bp open reading frame encoded a preprotein of 339 amino acids with a predicted molecular weight of 32 kDa. The pro-domain contained the conserved ERFNIN, GNYD, and GCNGG motifs, which are all characteristic of CTSL. Homology revealed that the deduced amino acid sequence of BSF CTSL shared 74.22-72.99% identity with Diptera flies. Immunohistochemical (IHC) analysis showed the CTSL was predominantly localized in the gut, especially in the midgut. The mRNA expression of CTSL in different larval stages was analyzed by quantitative real-time PCR (RT-qPCR), which revealed that CTSL was expressed in the second to sixth instar, with the highest expression in the fifth instar. Following an immune challenge in vivo using Escherichia coli (E. coli), CTSL mRNA was significantly up-regulated at 6 h post-stimulation. The Z-Phe-Arg-AMC was gradually cleaved by the BSFL extract after 3 h post-stimulation. These results shed light on the potential role of CTSL in the defense mechanism that helps BSFL to survive against pathogens in a microbial-rich environment.

Comparative Analysis of the Mitochondrial Genomes of Chloropidae and Their Implications for the Phylogeny of the Family.

Chloropidae, commonly known as grass flies, represent the most taxonomically diverse family of Diptera Carnoidea, comprising over 3000 described species worldwide. Previous phylogenetic studies of this family have predominantly relied on morphological characters, with mitochondrial genomes being reported in a few species. This study presents 11 newly sequenced mitochondrial genomes (10 Chloropidae and 1 Milichiidae) and provides the first comprehensive comparative analysis of mitochondrial genomes for Chloropidae. Apart from 37 standard genes and the control region, three conserved intergenic sequences across Diptera Cyclorrhapha were identified in all available chloropid mitochondrial genomes. Evolutionary rates within Chloropidae exhibit significant variation across subfamilies, with Chloropinae displaying higher rates than the other three subfamilies. Phylogenetic relationships based on mitochondrial genomes were inferred using maximum likelihood and Bayesian methods. The monophyly of Chloropidae and all four subfamilies is consistently strongly supported, while subfamily relationships within Chloropidae remain poorly resolved, possibly due to rapid evolution.

New records of Pseudopomyzidae in Brazil and description of the male of Latheticomyia infumata Wheeler (Diptera: Brachycera).

Latheticomyia Wheeler is recorded for the first time from Brazil, with records of Latheticomyia infumata Wheeler and Latheticomyia longiterebra Hennig. The male of L. infumata is described and the terminalia are illustrated. New records of Pseudopomyzella flava Hennig for the Brazilian Amazon are presented.

A catalog of the Chamaemyiidae of Chile (Diptera: Lauxanioidea).

A catalog of the Chamaemyiidae of Chile is provided. We present all valid names and synonyms for the 14 species and eight genera and subgenera distributed in the country, including information about name, author, year of publication, page number, type-species, type depository, type locality and references. The chamaemyiid fauna of Chile is small, with the largest genus, Ortalidina Blanchard having only five species. Species of the subgenus Xenoleucopis Malloch of the genus Leucopis Meigen (even if referred to only as sp.) are the most cited due to their apparent potential as biological control agents, or the many works recording their biology. The geographical distribution of the different species was compiled from bibliographic data and revised collections.

Puparium of Merosargus cingulatus Schiner, 1868 and Ptecticus lanei James, 1941 (Diptera: Stratiomyidae: Sarginae), with new geographical records for the species and a list of all known immatures of the subfamily.

The puparia of Merosargus cingulatus Schiner, 1868 and Ptecticus lanei James, 1941, two Neotropical species of Sarginae (Stratiomyidae), are described and illustrated based on 19 and 17 immatures of each species, respectively. The specimens were collected in rotting vegetal material in Carambe, state of Paran, Brazil. Images of reared adults of both species are provided, allowing future identifications of specimens. New distributional records include the first occurrences of M. cingulatus in the Brazilian states of Cear, Maranho, Mato Grosso do Sul, and Rio de Janeiro. With these two new descriptions, immature stages (6th instar and/or puparium) of 29 species of Sarginae are now known, with only eight species known from the Neotropical Region.

Illustrated identification key to females of the genus Sabethes Robineau-Desvoidy recorded from Brazil (Diptera: Culicidae), in dichotomous and interactive formats, including an updated list of species and new records for the states.

Female mosquitoes of the genus Sabethes Robineau-Desvoidy, 1827 are implicated in the transmission of several arboviruses, including yellow fever virus. Here, we present an illustrated species identification key for females of the genus Sabethes recorded in Brazil, except Sa. nitidus Theobald, 1901 and Sa. harbachi Nascimento-Pereira, Guimares, Loureno-de-Oliveira & Motta, 2021 as only the males of these species are known. The key is available in dichotomous and interactive formats. An updated list of the Sabethes species of Brazil and new occurrence records for the states of the country are provided. The type localities of four speciesSa. glaucodaemon (Dyar & Shannon, 1925), Sa. amazonicus Gordon & Evans, 1922, Sa. belisarioi Neiva, 1908 and Sa. soperi Lane & Cerqueira, 1942are corrected or restricted.

Smittia solominae sp. nov. (Diptera: Chironomidae: Orthocladiinae), living on ice of high mountain glaciers of the Elbrus Region (North Caucasus).

Illustrated morphological description with a study of DNA barcoding and biology of adult male, pupa and larva of Smittia solominae sp. nov., living on the ice surface of glaciers at an altitude of about 3000 m above sea level in the Elbrus region of the North Caucasus is given. DNA barcoding provided support that the new species unique within genus Smittia. The average interspecific distances between S. solominae sp. nov. and other Smittia from BOLD above 12% that correspond to species level.

Diadelophora, a new phorid genus from central and western Brazil (Diptera: Phoridae).

Diadelophora gen. nov, a conspicuous new genus of phorid flies is described based on two species from central and western Brazil, D. stilbella sp. nov. and D. inornata sp. nov. The new genus is positioned in the Thaumatoxena-group within the subfamily Phorinae, probably as sister group to Hypocerides Schmitz, 1915. The diagnostic features of Diadelophora are commented and illustrated, and the genus differences to Hypocerides are highlighted. The morphology of Diadelophora species is explored in detail with SEM, photos, and optical microscopy illustrations of structures of taxonomic relevance and other curious features of the genus.

New findings on Nilothauma Kieffer (Diptera: Chironomidae) from Brazil and Peru.

Two new species of Nilothauma from Brazil and Peru are described and illustrated based on adult males collected respectively in the central and western Amazon. In addition, new records of Nilothauma complicatum Mendes & Andersen, 2009 in Brazil are provided.