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Micro-computer tomography imaging is a fast and non-destructive data acquisition technique which can replace or complement the traditional investigation methodologies used in entomology to study morphology. In this paper, Synchrotron Radiation X-ray Phase-Contrast micro tomography (SR-PhC micro-CT) was combined with histology and scanning electron microscopy (SEM) observations to describe the abdominal organs of Pterostichus melas italicus Dejean, 1828 (Coleoptera, Carabidae). This species was used as a representative model because of its ecological role as a generalist predator in agroecosystems. SR-PhC micro-CT allowed us to identify in situ abdominal structures including dorsal vessel, digestive tract with Malpighian tubules, male reproductive system, ganglia, fat bodies, pygidial glands, muscles and tracheae. The histology was performed to define the tissue organization of the digestive and reproductive systems. SR-PhC micro-CT and 3D rendering provided more accurate information on shape and size of organs than histological and SEM analyses, respectively. The finding of this study was to describe the anatomy and histology of organs involved in crucial life history traits, such as reproduction, nutrition and excretion. High quality images and the supplementary video represent a significant advance in knowledge of the carabid anatomy and are a baseline for future research.

In the four typological ecosystems of the central part of the steppe zone of Ukraine, the study of apicomplex parasites for one type of beetle has been carried out. Variability of morphometric indices for the Gigaductus exiguus (Wellmer, 1911), which occurs in the intestinal tract of Pterostichus melas (Creutzer, 1799) was studied. There are significant differences in the characteristics of infection in various types of geobotanical conditions.The species of the G. exiguus is a typical unicellular parasite for P. melas. In the work 13 micrographs of gregarines are presented at different stages of life, which are extracted from the intestines. The article includes four tables of the species identification of the morphometric indices. All measurements are indicated in micrometers. The linear dimension of the gregarines gamonts is significantly different in comparison with the data of other authors. The results of morphometry for 59 detected gregarines are given: 24 organisms are presented in the form of a syzygium and 35 in the form of a gemont. The low intensity and extensiveness of infestation by the pseudonyms for P. melas is noted. Linear characteristics and morphometric indices (n = 35) coincide with the literary data. The length of the conjugate (TL) varies from 13,65 to 46,99 (x ± SD – 26,60 ± 12,17) μm. The length of the (LP) varies between 2,44 and 10,19 (4,78 ± 2,24) μm. Deitomerite Length (LD) 10,77–41,79 (21,88 ± 10,22) μm. The width of the protomerite (WP) is 3,65–9,49 (5,51 ± 1,99) μm. The width of the deitomerite (WD) is within the range 3,85–10,58 (6,24 ± 2,28) μm. The ratio of the length of protomerite to the total length of the (LP / TL) is 0,11–0,22 (0,18 ± 0,03). The width of the protomerite to the width of the (WP / WD) is 0,77–1,03 (0,89 ± 0,07). The linear dimensions of the siziges (n = 24) coincide with the data of the researchers. The ratio of the (PTL / STL) was 0,77–1,15 (0,96 ± 0,09). The ratio of the protomerite length to the protomerite of the satellite (PPL / SPL) is 0,84–1,68 (1,25 ± 0,23). The ratio of the protomerite width of the primitive to the satellite (PPWM / SPWM) is 0,78–1,19 (1,04 ± 0,10). The ratio of the (PDL/SDL) – 0,71–1,12 (0,91 ± 0,10). The ratio of the deutorite sweep width to the satellite deutomerite width (PDWM / SDWM) is 0,89–1,18 (1,06 ± 0,07). The result of morphometry is the identification of the species as Gigaductus exiguus (Wellmer, 1911).

Pterostichus melas melas (Creutzer, 1799) Erlinsbach (AG), Egg, 610 m, 642.9/251.8, 11.6.2013: 2 Ind. Nach einem regenreichen Frühjahr in der Nähe des Waldrandes in einer Magerwiese unter Falllaub gefunden. Die Unterart wurde zuletzt 2001 gemeldet. Die Art P. melas ist leicht mit dem häufigen P. melanarius (Illiger, 1798) zu verwechseln., Published as part of Hoess, René, 2016, Interessante Neufunde von Laufkäfern (Coleoptera: Carabidae) aus der Schweiz, pp. 53-67 in Entomo Helvetica 9 on page 65, DOI: 10.5169/seals-986145, http://zenodo.org/record/7901176

Landscape connectivity is a key issue of nature conservation and distance parameters are essential for the calculation of patch level metrics. For such calculations the so-called Euclidean and the least cost distance are the most widespread models. In the present work we tested both distance models for landscape connectivity, using connectivity metrics in the case of a grassland mosaic, and the ground beetle Pterostichus melas as a focal species. Our goal was to explore the dissimilarity between the two distance models and the consequent divergence from the calculated values of patch relevance in connectivity. We found that the two distance models calculated the distances similarly, but their estimations were more reliable over short distances (circa 500 m), than long distances (circa 3000 m). The variability in the importance of habitat patches (i.e. patch connectivity indices) was estimated by the difference between the two distance models (Euclidean vs. least cost) according to the patch size. The location of the habitat patches in the matrix seemed to be a more important factor than the habitat size in the estimation of connectivity. The uncertainty of three patch connectivity indices (Integral Index of Connectivity, Probability of Connectance and Flux) became high above a habitat size of 5 ha. Relevance of patches in maintaining connectivity varied even within small ranges depending on the estimator of distance, revealing the careful consideration of these methods in conservation planning.

This study draws attention to the toxicity of dimethoate at sub-lethal concentration to beneficial carabid beetles living in olive groves agroecosystem of Calabria, Italy. Short- and long-term effects of dimethoate on a non-target generalist predator in agroecosystems, Pterostichus melas italicus (Dejean, 1828) (Coleoptera, Carabidae) adults, were quantified by toxicity test, total haemocyte counts and morphometric analyses. In laboratory toxicity tests, beetles of both sexes exposed to field concentration of this toxicant showed a reduction of activity and a mortality of 10% after 72 h. Moreover, the impact of dimethoate on the total haemocyte counts (THCs) was recorded as a significantly lower number of circulating haemocytes in treated animals compared to controls at 48 h. Morphometric analyses showed that dimethoate caused long-term sub-lethal effects as a reduction of some morphometric parameters in P. melas italicus populations from two olive groves (treated and natural). In addition, a significant reduction in body size of females from long-term treated olive grove and a sexual dimorphism alteration were observed. As a result, data suggested that dimethoate may cause sub-lethal effects on this non-target carabid species.

Pterostichus melas (Creutzer, 1799) Pterostichus melas melas (Creutzer, 1799) [= depressus (Dejean, 1828)] References. Pterostichus melas depressus: Gu��orguiev 1998: 41 (Galičica). Material studied. Skopje, Katlanovo, 13.06.1996, 1 s., leg. S. Hristovski (cSH). Distribution. 37, 76., Published as part of Hristovski, Slav��o & Gu��orguiev, Borislav, 2015, Annotated catalogue of the carabid beetles of the Republic of Macedonia (Coleoptera: Carabidae), pp. 1-190 in Zootaxa 4002 (1) on page 131, DOI: 10.11646/zootaxa.4002.1.1, http://zenodo.org/record/238945, {"references":["Gueorguiev, B. V. (1998) Ground-beetles (Coleoptera: Carabidae) collected by Bulgarian zoologists in the Republic of Macedonia. Historia naturalis bulgarica, 9, 35 - 51."]}