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  • Open access
  • 96 Reads
Diplodomica III. Chemical Ecology of defensive secretions from neotropical archepelago. Isolation of 3.4-dimethoxyphenol from ejected secretion of endemic Cuban millipedes (Spirobolida, Rhinocricidae, Rhinocricus). Study case Rhinocricus duvernoyi Karch 1881, La Palma population
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Milipedes (Artropoda, Dipolopoda), are very ancient terrestrial invertebrates comprising around 14000 species distributed in all geographical areas of the planet. These organisms respond to any disturbance (predators) by ejecting a brown repugnatorial secretion, with purgent phenolic odor and with repellent action that can cause serious epidermal irritation to the attacker. The chemical composition of these secretions varies according to the taxonomic order. Species of the orders Julida, Spirobolida and Spirostreptida secrete p-benzoquinones, Polydesmida species discharge hydrogen cyanide and nitroalkanes, Glomerida and Polyzoniida eject alkaloids and also terpenoids such as ß-pinene and limonene. These defensive secretions constitute an ecosustainable source of biologically active secondary metabolites with potential broad-spectrum microbiocidal action. The Cuban archipelago mega-edaphofauna is characterized by endemic millipedes of the gen. Rhinocricus (R. duvernoyi and R. maximus) having the highest biomass index. These milipeds can ejaculate their secretions up to distances of 50 cm. The objective of the present communication is to report the majority composition of this secretion in individuals of the species Rhinocricus duvernoyi Karsch 1881 that inhabit the western zone of Cuba in ecogeographic formations of mogotes (karst), in La Palma (l= 83033'15" W, =22045'24 "N). The colected secretion, after a detailed chemical análisis (TLC, FTIR, CG-MS, RMN), revealed the existence of a majority componente, a new metabolite, of phenolic nature, (3,4-dimethoxyphenol) for the order Spirobolida, Family Rhinocricidae and Genus Rhinocricus, belonging to a population of the endemic millipede Rhinocricus duvernoyi Karch 1881, in the western eco-geographical zone of the Cuban archepelago La Palma (Pinar del Río). Biological activity determination is currently under development and will be published soon.

  • Open access
  • 41 Reads
Determinants of diversity of caterpillars, leaf miners and gallers on individual oak trees in a forest

The community of insect herbivores on individual host trees may depend on the history of the hosts - from ongoing ontogeny via recent microevolution to ancient phylogeny - but the relative importance of these scales remains unknown. We sampled spring caterpillars, leaf mines and leaf galls from sessile oaks (Quercus petraea) in a forest in western Poland. We assessed the effect of individual tree neighborhood, tree size, budburst phenology, as well as genetic traits on insect herbivore diversity and community composition. Overall, our results show that different scales of history act simultaneously, and do so differently in different functional groups.

Grant No. 2018/29/B/NZ8/00112 National Science Centre (Poland).

  • Open access
  • 56 Reads
Measurement of the exterior of the bees: a comparison of methods

Various methods and techniques are used to determine the race affiliation and grading of honey bees (Apis mellifera Linnaeus 1758; Hymenoptera: Apidae) by using a different number of evaluated characters. This complicates the comparative analysis of data obtained from different sources. At the same time, the use of equipment in measurements without taking into account distortion and calibration, leads to erroneous data.
The main objective of the study was to compare two measurement methods (using the MBS-9 stereo microscope and a personal computer using Altami Studio 3.4.0 software) of the exterior signs of honey bees. The operators alternately (three times) measured using first one measurement method (MBS-9) and then another (computer + Altami Studio 3.4.0).A comparison of the two measurement methods using nonparametric criteria made it possible to establish that the measurement results of some exterior features obtained using one method are significantly different from the results obtained using another measurement method. Based on the data obtained, the coefficients of variation were calculated between the averages over the measurements obtained by one operator and between the operators for each of the two measurement methods. Measurement using Altami Studio 3.4.0 allows you to get results with less trait variability between repeated measurements of one operator and between operators, compared to MBS-9. Using the analysis of variance, it was established that two factors influence the measurement results: the measurement method and the operator performing the measurement, as well as the interaction of these two factors. The use of software and repeated measurements in it will allow identifying operators prone to less variability of results, as well as control the accuracy of measurements.

  • Open access
  • 34 Reads
Ecosystem-scale distribution and phenology of Gonipterini weevils associated with Eucalyptus populnea in Central Queensland, Australia

The Gonipterini tribe (Coleoptera: Curculionidae) contains a number of species of economic significance, including several species of Gonipterus which are invasive pests of eucalypt plantations internationally. However, the inter-specific ecosystem-level interactions and population dynamics of many species are poorly understood within their native range. This study investigated the associations of two species of Oxyops and two species of Gonipterus from Central Queensland, Australia, including their phenology over the course of a year-long survey. A total of 102 Gonipterini weevils were found, with Oxyops fasciculatus being the most abundant. Weevils were only found in 12.1% of the Eucalyptus populnea saplings surveyed; however, saplings containing weevils contained an average of 1.8 weevils. Additionally, 19.6% of weevils were found in close proximity to another weevil at a micro-ecosystem scale (e.g., on the same leaf). Weevil numbers peaked in March at 17.2 adults/acre, with the lowest numbers found in June (3.6 adults/acre). One of the Oxyops species (an undescribed species known only from Central Queensland) was more commonly found on the leaves, compared to Gonipterus cinnamomeus which was more commonly located on the stem or petiole. These results provide insight into the population dynamics, interactions, and spatial and temporal resource partitioning between different Gonipterini species within their native range.

  • Open access
  • 44 Reads
Cuticular hydrocarbon profiling reveals chemotaxonomic diversity among Gonipterini weevils (Coleoptera: Curculionidae)

Cuticular hydrocarbons (CHCs) have been used as a chemotaxonomic tool to support the classification and identification of various insect species for decades. However, there have been limited research performed on the CHC profiles of weevils (Coleoptera: Curculionidae), despite the extensive diversity and ecological significance of this family. In this study, CHCs were extracted from fifteen Gonipterini weevil specimens from eastern Australia, comprising five species from three genera. Analysis by gas chromatography-mass spectrometry (GC-MS) revealed the presence of over 90 compounds, with the most abundant compounds including nonacosane, 7-methylheptacosane, heptacosane and hexacosane. Principal component analysis and hierarchical cluster analysis revealed Bryachus squamicollis to be the most dissimilar species in terms of its CHC profile, while the two Oxyops species showed relatively similar CHC profiles. The results may support the use of CHC profiling as a chemotaxonomic tool for the identification and delineation of various Gonipterini genera and species.

  • Open access
  • 142 Reads
Biodiversity in the Sulfidic Sections of the Frasassi Caves, Italy

The caves located in the Frasassi Gorge, Marche region (central Italy) contain numerous sulfidic habitats that represent hotspots of subterranean biodiversity. They host unusually rich and diverse invertebrate communities that display specific adaptations to cave life. As in other sulfidic subterranean ecosystems discovered worldwide (Movile Cave in Romania, Ayyalon Cave in Israel, Melissotrypa Cave in Greece, and Tashan Cave in Iran), primary production in Frasassi's sulfidic sections is fuelled by chemoautotrophic sulfur-oxidizing microorganisms. Conversely, few animals are present in cave sections where trophic resources are scarce and dependant on surface input, such as upper fossil passages and cave pools filled with percolation water from the epikarst. A single vertebrate species, the salamander Speleomantes italicus (Dunn, 1923), and numerous species of invertebrates have been identified in Frasassi's sulfidic sections, of which 22 are stygobionts and 5 are troglobionts (including 12 endemic species). Specific adaptations to the extreme environmental conditions encountered there, such as highly toxic sulfide levels and low pH, have been identified in some species. Notably, symbioses observed between amphipods of the genus Niphargus and filamentous sulfur-oxidizing bacteria belonging to the genus Thiothrix may help them better cope with sulfide toxicity.

  • Open access
  • 49 Reads
Insights into the nuclear and mitochondrial genetic diversity of local Tuva population of domestic reindeer.
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The reindeer of the Tuva population inhabiting the south of Eastern Siberia and belong to one of the southernmost populations of domestic reindeer. The population census size of those reindeer was declined dramatically from 15,000 in 1990 to 1,500 individuals in 2019. A genetic study of this population is mandatory for assessing the risk of loss of its genetic diversity in order to develop the proper management strategies for preserving this unique genetic resource. In our study, we examined genetic diversity of Tuva reindeer based on both a high-density SNP genotypes analysis (n=12) and a complete cytochrome b (cytb) sequences (1,140 bp) (n=6). To find out a possible genetic contribution toward the Tuva reindeer population structure, SNP genotypes and cytb sequences of all officially recognized breeds in Russia were added to our datasets. All genetic diversity indices calculated based on both nuclear and mitochondrial genomic data were lowest in Tuva population. Median-joining network, a principal component analysis and FST-based Neighbor-Net tree showed that Tuva population was most distant, while other breeds formed well-separated clusters according to their geographic locations. The low level of genetic diversity of the Tuva population observed in our study, based on studies involving a genome-wide approach, as well as a complete cytochrome b sequences, indicated the need to take appropriate measures to avoid negative consequences for this domestic reindeer. This study was supported by RSF-21-16-00071 and Russian Ministry of Science and Higher Education-0445-2019-0024.

  • Open access
  • 55 Reads
Composition and Ecology of the Insect Community and
Microbiota in Galls on a Hawkweed Hieracium × robustum Fries, 1848

The gall-wasp Aulacidea hieracii L., 1758 (Hymenoptera: Cynipidae) forms a stem gall on the hawkweed Hieracium × robustum Fries, 1848 (Asteraceae), a weedy herb that grows in the steppe biotopes of Eurasia. In its turn, gall-former serves as food for a large number of parasitoids and predators, which also live and develop inside and outside the gall. Moreover, the inhabitants of the galls are consumed by birds. In addition, a specific microbiota develops inside the gall, which includes representatives of gram-negative bacteria Pseudomonas rhizosphaerae, Curtobacterium flaccumfaciens, Pantoea agglomerans and fungi Alternaria alternata. The authors found out the composition of parasitoids, predators, inquilines, and microorganisms for a gall on the hawkweed. For the first time, studies were carried out on the development of the moth caterpillars Oxyptilus chrysodactyla ([Denis & Schiffermüller], 1775) on the hawkweed H. robustum. We found that the caterpillars of the moths cohabit on their fodder plant on the surface of the gall, together with the larvae of gall-wasps. Notably, the gall-wasp larvae are the first to inhabit the plant. A parasitoid from the Pimpilinae family was also bred from the moth caterpillars. Thus, the gall is a complex ecosystem, the study of which is not only of fundamental importance, but can be useful for solving the problems of the practical application of biological agents for weed control or for combating harmful species of gall-formers.

  • Open access
  • 56 Reads
Invasive raccoon dog (Nyctereutes procyonoides) and raccoon (Procyon lotor) monitoring in Lithuania based on camera traps data

Invasive mammal species outside their natural range are causing damage to the native ecosystems. Raccoon dogs were first observed in Lithuania in 1948 and since then spread across the country. Surveys of this species stopped in 1997, therefore numbers and trends currently are unknown. Raccoons were first observed in 2012, with only a few sporadical reports over the decade. Both species are listed as an EU species of concern. Between September 2019 and July 2021 we evaluated distribution and densities of these animals using camera traps (system with a motion trigger/sensor that activates a camera to take a photograph when an animal is present) at 85 locations with a total sampling effort of 11501 camera trap days. Raccoon dog was identified in 57 locations (67.1 % of all surveyed) and raccoon 1 location (1.2 %). The average relative shooting frequency of raccoon dogs was 5.12 photos/100 days and that of raccoons was 0.18 photos/100 days. The abundance of raccoon dog was not uniform. In northeastern part of Lithuania their relative shooting frequency was significantly higher than in western part (6.26 and 2.31 photos/100 days, respectively; p < 0.05). Raccoons were present in only one location, however, during the study period they were registered 21 times. This indicates that a viable population has developed and it can become a source of further invasion in the nearest future, requiring immediate control actions. Research was funded by contract No. 05.5.1-APVA-V-018-01-0012.

  • Open access
  • 33 Reads
Filling Biodiversity Knowledge Gaps: Sponges (Porifera: Demospongiae) Recorded off San Jorge Gulf (Argentina), SW Atlantic Ocean

In Argentina, our knowledge on the biodiversity of marine Porifera is closely related to the concentration of the sampling effort. Coastal areas such as Buenos Aires and Tierra del Fuego have several records, while the majority of the continental shelf have few or no records at all. In December 2020, the RV “Victor Angelescu” performed a regular stock assessment expedition in order to evaluate the population of the Argentinean squid Illex argentinus off San Jorge Gulf (44°S-46°S, 84m-114m). Sampling was designed using bottom trawls. At 23 random sampling sites, the invertebrate by-catch was preserved frozen and studied at the Benthos Laboratory of the INIDEP. According to our knowledge, there are no specific records of sponge species in this area, only sparse mentions as a general group in technical reports. Our results showed that sponges were conspicuous and abundant components in the benthic communities of the area. They represented up to 40% of the total invertebrate bycatch (with an average value of ~130 kg.mn2 per site). Surprisingly, the species Tedania (Tedaniopsis) mucosa Thiele, 1905 was found to be dominant in the area and was recorded in 22 sites, reaching up to 34 % of the wet biomass (average of ~100 kg.nm2). Other recorded species belong to the genera Isodictya, Iophon, Clathria, Haliclona, Tedania and Siphonochalina. The results of this study contribute to fill in the gaps on the distribution of the sponges in the continental shelf of Argentina.

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