We performed a study of the nonlinear optical properties of chemically purified chitin and insect cuticle using two-photon excited autofluorescence (TPEF) and second-harmonic generation (SHG) ...microscopy. Excitation spectrum, fluorescence time, polarization sensitivity, and bleaching speed were measured. We have found that the maximum autofluorescence signal requires an excitation wavelength below 850 nm. At longer wavelengths, we were able to penetrate more than 150-μm deep into the sample through the chitinous structures. The excitation power was kept below 10 mW (at the sample) in order to diminish bleaching. The SHG from the purified chitin was confirmed by spectral- and time-resolved measurements. Two cave-dwelling, depigmented, insect species were analyzed and three-dimensional images of the cuticular structures were obtained.
In this paper, the genus
Fitzinger, 1833 in Serbia is reviewed. All previous literature data on this genus from Serbia are summarised and used to discuss its distribution in the country and create ...distribution maps, supplemented by new material collected by the authors. All Serbian species are figured. For each species, a brief description of the examined specimens, data on previous findings in Serbia, the material (including types) that were analysed, the distribution and habitats in Serbia they inhabit, as well as remarks on specific species are given. A new species,
Gojšina & Dedov,
, is described from a pit on Mt. Devica in eastern Serbia.
(O. Boettger, 1880) is reported for the first time for the territory of Serbia. As some
species have a narrow geographical range and prefer certain habitats, they are particularly vulnerable to habitat changes, which is also discussed in the paper. An identification key for all hitherto known Serbian species is given.
Bat guano is an important source of microbial diversity in caves and can be a source of potential pathogens.
Laemostenus
(
Pristonychus
)
punctatus
is a guanophilic ground beetle species, which ...pygidial gland secretion exhibits action against pathogenic and other microbes. The distribution and diversity of microbes in bat guano from a karstic cave were determined in this study. Additionally, antimicrobial activity of the pygidial gland secretion of
L
. (
P
.)
punctatus
against guano-dwelling microbes was tested; minimal inhibitory concentration (MIC) and chemical composition of the secretion were analyzed. In total, 63 different bacterial species and 16 fungal morphotypes were isolated from guano samples by the cultivation method and confirmed using and phenotypic characterization and molecular identification. There was a difference in the composition of certain microorganisms between the sampling points (cave locations) and between the guano layers. The largest number of bacterial isolates belongs to the genera
Lysinibacillus
and
Paenibacillus
, while
Pseudomonas
species were highly abundant at the innermost sampling point. For the guanophilic fungi, the majority are ascomycetes, with
Penicillium
and
Aspergillus
as the most dominant genera.
Meyerozyma guilliermondii
was the only yeast species found in the guano samples. The most sensitive isolates were
Enterococcus eurekensis
(MIC 0.007 mg/mL) and
Escherichia fergusonii
(MIC 0.028 mg/mL). The most sensitive fungal isolates were
M. guilliermondii
,
Penicillium expansum
, and
Trichoderma harzianum
(MIC 0.15 mg/mL). This study opens a new possibility for better understanding of ecological relations between microorganisms and troglophilic ground beetles and for detailed investigations of morpho-anatomical aspects of pygidial glands.
Duvalius semecensis tarensis
ssp. nov.
from two subterranean sites situated on Mt. Tara (western Serbia) is described, illustrated and compared with its most related congeners. It is provisionally ...placed in the subgenus Biharotrechus Bokor, 1922. The new subspecies is characterized by a depigmented, medium-sized body, the presence of reduced eyes, deep and complete frontal furrows, two pairs of discal setae in third elytral striae, as well as by the shape of aedeagus. It inhabits caves on Mt. Tara and is endemic of this mountain. Data on the distribution and bionomy of the new subspecies are given. Its closest relative, Duvalius (Biharotrechus) semecensis semecensis Winkler, 1926, is redescribed and we designated its holotype by monotypy. A key for the identification and an annotated catalogue of Serbian
Biharotrechus
and
Duvalius
s. str. taxa are also provided.
Two new subterranean leiodid taxa of the genus Spelaeobates Müller, 1901 from three pits in northern Dalmatia (Croatia), S. coriniensis sp. nov. and S. coriniensis nonveilleri ssp. nov., are ...described. The morphological traits of the new taxa are enumerated and illustrated. These two taxa are placed in the subgenus Spelaeobates Müller, 1901. The relationships of these two taxa and their close relatives are clarified. Data on the sexual dimorphism of the two new taxa and on the intrasubspecific variability of S. coriniensis nonveilleri ssp. nov. are presented. We also redescribed S. novaki, the type species of both the genus Spelaeobates and the subgenus Spelaeobates and the closest relative of the newly described species. A key for identification of the taxa of the genus Spelaeobates is included. The new taxa are endemic to the Dinaric Alps of Croatia. Spelaeobates (Pretneriella) kraussi Müller, 1903 and S. (P.) pharensis langhofferi Müller, 1931 were found for the first time outside their type locality.
It is a commonly known fact that all ground beetles possess abdominal pygidial glands with relatively similar gross structure and function among species. Still, morphology of the glands and ...composition of their secretions have not been studied in most ground beetle species. These exocrine glands and their products are mainly associated with defence in natural environments. In this paper, we studied three predatory ground beetle species of the genus
Carabus
Linnaeus, 1758, namely
C
. (
Archicarabus
)
montivagus
Palliardi, 1825,
C
. (
Megodontus
)
caelatus
Fabricius, 1801, and
C
. (
M.
)
violaceus
Linnaeus, 1758, to identify chemical components of their pygidial gland secretions. Altogether, 10 carboxylic acids were isolated from the analysed secretions two from the secretion of
C
. (
A
.)
montivagus
, 10 from that of
C
. (
M
.)
caelatus
, and nine from that of
C
. (
M.
)
violaceus
. The finding of 2-hexenoic acid in the secretion of
C
. (
M
.)
caelatus
is the first finding of it within the entire subfamily Carabinae. In addition, we also analysed the morphology of glands of the species
C
. (
M.
)
violaceus.
Pygidial glands are of great importance to ground beetles for defense against predators, especially for the species that live in subterranean habitats. The purpose of our study is to better ...understand the chemistry of the pygidial gland secretions of subterranean ground beetles, as well as the function and structure of the glands. We studied both the chemical composition of the pygidial gland secretion and morphology of the glands in adults of the troglophilic ground beetle species Laemostenus (Antisphodrus) cavicola (Schaum, 1858). The chemical composition of its defensive secretion was revealed using gas chromatography-mass spectrometry (GC-MS), while pygidial gland morphology of the beetle was investigated using bright-field microcopy. In total, seven chemical compounds were detected in the secretion mixture. Formic acid was the most dominant compound, followed by dodecyl acetate and undecane. Other chemicals were present in minor amounts. The morphological structure of the pygidial glands of L. (A.) cavicola was compared with the structure of the glands of the related congeneric troglophilic species Laemostenus (Pristonychus) punctatus (Dejean, 1828). Summary data on the semiochemicals that have been recorded so far in subterranean ground beetle species are presented, and the differences in the chemical composition of the secretions between and among troglobitic and troglophilic species are discussed. So far, forty-four compounds have been detected in four subterranean ground beetle species (two troglobites belonging to the tribe Trechini and two troglophiles belonging to the tribe Sphodrini). The results of this study indicate the great diversity of chemicals in the pygidial gland secretions of subterranean ground beetles.
This study investigates factors contributing to public perception of and behaviors related to air pollution in Serbia. A range of multidimensional indicators, including demographic and socioeconomic ...features, health status data, and living environment factors, were utilized to evaluate observed awareness and exposure activities. Air pollution is a serious health concern in many areas of Serbia, particularly during the cold season when emissions from the heating sector contribute to high levels of particulate matter. In the period from March to May 2023, a nationwide survey was conducted to gather empirical data and insights that can assist policymakers in the creation of public-health strategies. A set of research questions included the perception of air-pollution impact and citizens’ responses to eight pre-defined exposure-reduction activities. Statistical procedures (a chi-square test of independence, a Mann–Whitney U test, and a Kruskal–Wallis H test) were applied to isolate driving factors in the public response to increased air-pollution levels. The findings suggest a “gap” between risk understanding and risk-reducing behaviors. To address this issue and to ensure that regulations are implemented effectively, it is crucial to prioritize education, develop communication strategies, increase local interventions, and target vulnerable population groups.
The Balkan region is rich in limestone deposits, which have created one of the largest hotspots of subterranean biodiversity. This paper gives an overview of the diversity of subterranean terrestrial ...arthropods in Resava Cave in eastern Serbia. This cave is protected and has the status of a natural monument. At the same time, it is one of the most visited caves in Serbia and its surroundings. Our study comprises the results of three years of biospeleological investigations of the famous Serbian cave in combination with data from the few available literature sources on the arthropod fauna of the cave. The arthropod samples were collected both manually and with pitfall traps. A total of 107 arthropod species from the four major subphyla were registered in the cave: 66 species of Hexapoda, 27 species of Chelicerata, 11 species of Myriapoda and three species of Crustacea. For four troglobitic, 16 troglophilic and 87 trogloxenic species recorded in the cave, descriptions of their microhabitats and information on their distribution in the cave are given. Considering the medium size of Resava Cave and the lack of permanent water flow in the two main levels on the one hand, and the large number of arthropod species recorded on the other, the cave is relatively rich in hypogean terrestrial arthropod fauna compared to other caves in Serbia that have been biospeleologically studied so far.
