Future Proteins: Sustainable Diets for Tenebrio molitor Rearing Composed of Food By-Products.

Since the human population is continuously growing, sufficient food with low environmental impact is required. Especially, the challenge of providing proteins will deepen and insects can contribute to a more sustainable and efficient source of protein for human consumption. Tenebrio molitor larvae are highly nutritious and rearing mealworms is more environmentally friendly compared to the production of traditional livestock meat. To use T. molitor as a more sustainable alternative to conventional proteins, it is essential to apply diets from a local and sustainable source. Therefore, the objective of this study was to find local by-products or leftovers which can be used in mass production of larvae as a main substrate. Feeding trials investigating twenty-nine different substrates were conducted to evaluate larval growth performance and adult reproduction by determining development times, survival rates, biomass, and fecundity. Several suitable by-products were identified that can be used in high quantities as single component diet for T. molitor rearing, revealing a high survival rate, short development time, high mean total biomass, and successful breeding. The most successful substrate-malt residual pellets-was found to be an alternative to the most used substrate, wheat bran. Furthermore, corn germ meal, sweet chestnuts, bread remains, soybeans, sweet potatoes, and wheat germs have been discovered to be suitable diets for T. molitor. Moreover, the findings of this study contribute towards using several substrates as supplements.

Tenebrio molitor (Linnaeus, 1758): Microbiological Screening of Feed for a Safe Food Choice.

As a result of the increasing focus on alternative protein sources which are ideally still sustainable, the yellow mealworm, Tenebrio molitor, has come into focus. To verify its suitability as a food source in relation to human health, an analysis of the microbiome of larvae of T. molitor is pertinent. Subsequently, the focus of this study was, on the one hand, to analyze the influence of the substrate on the microbial load of the larvae microbiome, and, on the other hand, to determine which processing methods ensure the risk-free consumption of mealworms. For this purpose, mealworms were grown on 10 different substrates derived from by-products of food production (malt residual pellets, corn germ meal, chestnut breakage and meal, wheat bran, bread remains, draff, nettle, hemp seed oil cake, oyster mushrooms with coffee grounds, pumpkin seed oil cake) and microbial loads were analyzed using different selective media. Further starvation/defecation and heating (850 W for 10 min) methods were used to investigate how the reduction of microorganisms is enabled by these methods. The results showed that there was no significant relationship between the microbial load of the substrate and the mealworm. Starvation and defecation led to a lower stock of microorganisms. Heating led to a significant microbial reduction in non-defecated mealworms. The group of defecated and heated mealworms showed no detectable microbial load. In conclusion, firstly, the choice of substrate showed no effect on the microbial load of larvae of Tenebrio molitor and secondly, heating and starvation allow risk-free consumption. This study makes an important contribution for evaluating the safety of mealworms as a sustainable protein source in human nutrition.

Hidden biodiversity in microarthropods (Acari, Oribatida, Eremaeoidea, Caleremaeus).

A challenge for taxonomists all over the world and across all taxonomic groups is recognizing and delimiting species, and cryptic species are even more challenging. However, an accurate identification is fundamental for all biological studies from ecology to conversation biology. We used a multidisciplinary approach including genetics as well as morphological and ecological data to assess if an easily recognizable, widely distributed and euryoecious mite taxon represents one and the same species. According to phylogenetic (based on mitochondrial and nuclear genes) and species delimitation analyses, five distinct putative species were detected and supported by high genetic distances. These genetic lineages correlate well with ecological data, and each species could be associated to its own (micro)habitat. Subsequently, slight morphological differences were found and provide additional evidence that five different species occur in Central and Southern Europe. The minuteness and the characteristic habitus of Caleremaeus monilipes tempted to neglect potential higher species diversity. This problem might concern several other "well-known" euryoecious microarthropods. Five new species of the genus Caleremaeus are described, namely Caleremaeus mentobellus sp. nov., C. lignophilus sp. nov., C. alpinus sp. nov., C. elevatus sp. nov., and C. hispanicus sp. nov. Additionally, a morphological evaluation of C. monilipes is presented.

A taxonomist's nightmare - Cryptic diversity in Caribbean intertidal arthropods (Arachnida, Acari, Oribatida).

There has been a long controversy about what defines a species and how to delimitate them which resulted in the existence of more than two dozen different species concepts. Recent research on so-called "cryptic species" heated up this debate as some scientists argue that these cryptic species are only a result of incompatible species concepts. While this may be true, we should keep in mind that all concepts are nothing more than human constructs and that the phenomenon of high phenotypic similarity despite reproductive isolation is real. To investigate and understand this phenomenon it is important to classify and name cryptic species as it allows to communicate them with other fields of science that use Linnaean binomials. To provide a common framework for the description of cryptic species, we propose a possible protocol of how to formally name and describe these taxa in practice. The most important point of this protocol is to explain which species concept was used to delimitate the cryptic taxon. As a model, we present the case of the allegedly widespread Caribbean intertidal mite Thalassozetes barbara, which in fact consists of seven phenotypically very similar but genetically distinct species. All species are island or short-range endemics with poor dispersal abilities that have evolved in geographic isolation. Stabilizing selection caused by the extreme conditions of the intertidal environment is suggested to be responsible for the morphological stasis of this cryptic species complex.

Use Them for What They Are Good at: Mealworms in Circular Food Systems.

Future food systems must provide more food produced on less land with fewer greenhouse gas emissions if the goal is to keep planetary boundaries within safe zones. The valorisation of agricultural and industrial by-products by insects is an increasingly investigated strategy, because it can help to address resource scarcities and related environmental issues. Thus, insects for food and feed have gained increasing attention as a sustainable protein production strategy in circular food systems lately. In this article, we provide an overview on by-products, which have already been fed to T. molitor (mealworms), a common edible insect species. In addition, we investigate other by-products in Austria, which can be suitable substrates for T. molitor farming. We also provide an overview and discuss different perspectives on T. molitor and link it with the circular economy concept. We identify several future research fields, such as more comprehensive feeding trials with other by-products, feeding trials with mealworms over several generations, and the development of a standardized framework for insect rearing trials. In addition, we argue that due to their ability to convert organic by-products from agricultural and industrial processes into biomass in an efficient way, T. molitor can contribute towards resource-efficient and circular food and feed production. However, several hurdles, such as legal frameworks, need to be adapted, and further research is needed to fully reap the benefits of mealworm farming.

The Caribbean enigma: the presence of unusual cryptic diversity in intertidal mites (Arachnida, Acari, Oribatida).

The definition, as well as the existence of cryptic species, is still a subject of controversial debates. Some scientists claim that cryptic diversity is a real phenomenon that should be extensively studied while others argue that cryptic species do not exist as they are nothing more than an incompatibility of species concepts. We investigated the enigmatic case of two widely distributed Caribbean intertidal oribatid mites, Carinozetes bermudensis and Carinozetes mangrovi, consisting of five distinct genetic lineages. Morphological features allowing to clearly distinguish between these lineages are absent, and despite certain congruence with genetic data, comprehensive morphometric analyses also do not show clear separation. Species delimitation analyses based on COI sequence data, on the other hand, suggest five distinct genetic species. Despite the lack of diagnostic characters for these suggested species, the lineages can be classified at least into two morphological groups, the bermudensis and the mangrovi group which can only be distinguished by the arrangement of cuticular ventral carinae. Specimens within a group show nearly identical phenotypes, impeding morphological identification and hence rendering the found diversity cryptic. Stabilizing selection caused by the extreme conditions of the intertidal environment is suggested to be responsible for the found morphological stasis. The genetic lineages show more or less clear geographic patterns; in C. mangrovi, there is a northern, an Antillean, and a Pacific lineage, whereas in C. bermudensis, there is a Bermudian and a Caribbean lineage. In a few places, e.g., the Bahamas and Panama, distributions may overlap. Neither the found biogeographic pattern nor the observed ecological needs could explain the reason for the genetic diversification of Caribbean Carinozetes.

New and cryptic species of intertidal mites (Acari, Oribatida) from the Western Caribbean - an integrative approach.

The present study highlights the distribution, systematics, morphology, genetics, and ecology of two newly discovered intertidal oribatid mites from the Western Caribbean. The fortuyniid Litoribates floridae sp. nov. represents a cryptic species as it looks nearly identical to L. bonairensis. The two species can be distinguished only by subtle morphological and morphometric characteristics, whereas cytochrome oxidase subunit I gene sequences clearly separate the two taxa. The absence of morphological divergence in these disjunct species may have resulted from stabilizing selection due to the extreme intertidal environment. Litoribates floridae sp. nov. is presently known from the Florida Keys, primarily in mangrove leaf litter. The selenoribatid Thalassozetes balboa sp. nov. can be distinguished from all known congeners by a unique cuticular notogastral pattern, the presence of only two pairs of adanal setae, and two ventral teeth on each leg claw. It is morphologically most similar to T. barbara from the Eastern Caribbean. Thalassozetes balboa sp. nov. was found in Panama and Florida. This species usually occurs on rocky substrate and feeds on the intertidal alga Bostrychia. Litoribates floridaehttp://www.zoobank.org/urn:lsid:zoobank.org:act:A4B830FC-A03F-405D-9DE4-DE4C39DB6211 Thalassozetes balboahttp://www.zoobank.org/urn:lsid:zoobank.org:act:EBF8C435-5C07-4B0E-8279-2101DC9E2CD4.

Extracting the invisible: obtaining high quality DNA is a challenging task in small arthropods.

BACKGROUND: The application of an appropriate extraction method is a relevant factor for the success of all molecular studies. METHODS: Seven different DNA extraction methods suitable for high-throughput DNA sequencing with very small arthropods were compared by applying nine different protocols: three silica gel based spin methods, two cetyltrimethyl ammonium bromide (CTAB) based ones (one with an additional silica membrane), a protein precipitation method and a method based on a chelating resin (applying different protocols). The quantity (concentration) and quality (degradation, contamination, polymerase chain reaction (PCR) and sequencing success) of the extracted DNA as well as the costs, preparation times, user friendliness, and required supplies were compared across these methods. To assess the DNA quantity, two different DNA concentration measurements were applied. Additionally, the effect of varying amounts of starting material (different body sizes), variable lysis temperatures and mixing during DNA extraction was evaluated. RESULTS: Although low DNA concentrations were measured for all methods, the results showed that-with the exception of two methods-the PCR success was 100%. However, other parameters show vast differences. The time taken to perform DNA extraction varied from 20 min to 2.5 h (Chelex vs. CTAB) and the costs from 0.02 to 3.46 € (Chelex vs. QIAamp kit) per sample. High quality genomic DNA was only gained from four methods. Results of DNA quantity measurements further indicated that some devices cannot deal with small amounts of DNA and show variant results. DISCUSSION: In conclusion, using Chelex (chelating resin) turned out as a rapid, low-cost method which can provide high quality DNA for different kinds of molecular investigations.

Systematics, genetics, and biogeography of intertidal mites (Acari, Oribatida) from the Andaman Sea and Strait of Malacca.

This study demonstrates for the first time the presence of marine-associated mites in the Andaman Sea and Strait of Malacca and reveals a relatively high diversity of these taxa with six species from two different families: Selenoribatidae and Fortuyniidae. Indopacifica, a new genus of Selenoribatidae, is described from Thailand and Malaysia, with two new species, Indopacifica pantai n. sp. and Indopacifica parva n. sp. The genus is characterized by the unique combination of following characters: lacking lamellar ridges, incomplete dorsosejugal suture, fourteen pairs of notogastral setae, and presence of epimeral foveae. A phylogenetic reconstruction based on 18S ribosomal RNA sequences clearly confirms the distinctness of the new genus Indopacifica and places it close to the genus Rhizophobates. The lack of molecular genetic data of possible relatives impedes a clear assessment, and hence, we emphasize the need for further combined approaches using morphological and molecular genetic sequence data. All species show wide distribution areas within this geographic region suggesting that these taxa are good dispersers despite their minute size and wingless body. Molecular genetic data demonstrate recent gene flow between far distant populations of I. pantai n. sp. from the coasts of Thailand and two islands of Malaysia and hence confirm this assumption. The seasonally changing surface currents within this geographic area may favor hydrochorous dispersal and hence genetic exchange. Nevertheless, morphometric data show a slight trend to morphological divergence among the studied populations, whereas this variation is suggested to be a result of genetic drift but also of habitat differences in one population of Alismobates pseudoreticulatus.

Schusteria marina sp. nov. (Acari, Oribatida, Selenoribatidae) an intertidal mite from Caribbean coasts, with remarks on taxonomy, biogeography, and ecology.

Schusteria marina sp. nov. is a newly discovered intertidal mite species found on the Lesser Antillean Islands of Martinique and Grenada. It represents the first record of the genus Schusteria within the Caribbean area. Schusteria marina sp. nov. is very similar to the type species, S. littorea from Brazil, but can be distinguished by its smaller body size, a median sternal dark sclerotized small ridge on epimeron I and a few other less pronounced differences. Both species are closely related and form a Western Atlantic Schusteria clade, which is characterized by the possession of a pair of faint anterior epimeral ridges. Schusteria marina sp. nov. occurs on different littoral substrates, e.g. mangrove roots, anthropogenic concrete structures, but seems to be associated with an intertidal red alga belonging to the genus Bostrychia Montagne, 1842 growing on these substrates. http://zoobank.org/urn:lsid:zoobank.org:pub:C246533E-D108-4F2C-8577-545C059D46CE.

Hidden in the mangrove forest: the cryptic intertidal mite Carinozetes mangrovi sp. nov. (Acari, Oribatida, Selenoribatidae).

The small archipelago of Bermuda is a geologically young landmass in the Western Atlantic Ocean and recently turned out to be inhabited by a number of intertidal oribatid mites. One newly described species, Carinozetes bermudensis, showed an unusual vast range of habitats like sandy beaches, rocky substrate and mangroves. In the present study, 13 Bermudian populations of C. bermudensis were analysed to verify species integrity of specimens from different microhabitats. A morphometric analysis of 17 continuous variables as well as a molecular genetic investigation of the mitochondrial cytochrome oxidase subunit I revealed the existence of a new species Carinozetes mangrovi sp. nov., inhabiting exclusively intertidal algae growing on mangrove roots. Although both species are morphologically nearly identical, the configuration of the genus-specific ventral carinae represents a clear diagnostic character. The high genetic divergence of approximately 12 % of the cytochrome oxidase subunit I gene sequence between C. bermudensis and C. mangrovi sp. nov. suggests that these two species diverged before the emergence of the Bermuda islands. Accordingly, both of them are older than the geologically young archipelago of Bermuda.