No abstract

During the growth period, in surface habitats, spiders catch enough prey to feed normally. In contrast, in the cave entrance zone, prey may be relatively scarce. Meta menardi inhabits this cave section, resulting in temporary starvation. We studied structural changes in the midgut epithelial cells of M. menardi during a short-term and a medium-term controlled starvation to mimic the occasional starvation in caves, during spring and autumn. Digestive cells, secretory cells and adipocytes were examined before the experimental starvation, in the middle and at the end of starvation. We used light microscopy, transmission electron microscopy and specific histochemical methods for the detection of lipids, polysaccharides and proteins. Detection of lysosomes, autolysosomes and apoptosis was also carried out. The general structures of the cells did not change during the experimental starvation in either season, while some specific differences in the ultrastructure were observed. In both sexes, in both seasons, the amounts of lipids, glycogen and proteins decreased during starvation. Larger amounts of lipids were found in autumn, while there were no significant differences in the amounts of glycogen and proteins. In both sexes, in both seasons, autophagy and apoptosis intensified with starvation in progress, but more intensively in females. Thus, autumn individuals, in contrast to spring ones, compile energy-supplying stores to confront the subsequent winter deficiency of prey in caves, while the cellular ultrastructures undergo the same starvation-dependant changes at any time during the growth period.

Terrestrial animals in subterranean habitats are often classified according to their degree of morphological or ecological specialization to the subterranean environment. The commonly held view is that, as distance into a cave increases, the frequency of morphologically specialized, i.e., troglomorphic, species or ecological specialization will increase. We tested this hypothesis for the fauna in 54 caves in Slovenia-the classical land for subterranean biology. We found that there exist two ecologically well separated terrestrial subsurface faunas: one shallow and one deep. 1) The shallow subterranean fauna, adapted to the terrestrial shallow subterranean habitats (SSHs) in the upper 10 m of subsurface strata, is most diverse. It consists of randomly distributed non-troglobionts and a major group of troglobionts adapted to the soil root zone. 2) The deep subterranean fauna is represented by a minor group of troglobionts, adapted to caves. Troglobionts are strictly divided between the two faunas. There is strong evidence that in karstic ecosystems with deep-rooted vegetation this might be a global pattern, or that in these locations only the shallow subterranean fauna exist.

In the years 1977-2001, the fauna of and ecological conditions in 55 cavities – caves and artificial tunnels – in northern and central Slovenia were systematically investigated. Zoogeographically, this is the meeting point of the Alpine, Pannonian and Dinaric biome. This article lists 321 terrestrial genera, 456 species and 100 subspecies belonging to 183 families, that had been recorded by 2005 in cavities of this region in the course of our own investigations, and that have been cited in the references. This taxonomical review serves as a foundation for understanding ecological and other treatise on the terrestrial fauna in the hypogean habitats of northern and central Slovenia, those that have been published ones, as well as those in preparation. The overview of the systematically investigated cavities, and the review of the methods and techniques used has been added to provide general information about the morphology of these caves, and the ecological research within them.   V letih 1977-2001 smo sistematsko raziskovali kopensko favno in ekološke razmere v 55 votlinah – jamah in izkopanih rovih – severne in osrednje Slovenije. Zoogeografsko je to ozemlje na stičišču alpskega, panonskega in deloma dinarskega bioma. V članku je pregled 321 rodov, 456 vrst in 100 podvrst živali iz 183 družin, ki so bile do leta 2005 najdene v votlinah tega območja med lastnimi raziskavami ter po podatkih iz citirane literature. Taksonomski pregled je osnova in opora za razumevanje ekoloških ter drugih razprav o kopenski favni v podzemeljskih habitatih severne in osrednje Slovenije, ki so že objavljene in ki jih pripravljamo. V nadaljevanju so predstavljene votline, v katerih so potekale sistematske ekološke raziskave, ter naštete uporabljene metode in tehnike, s čimer je omogočen vpogled v morfologijo ekološko raziskanih votlin ter metode raziskovanja

The cave cricket Troglophilus neglectus regularly overwinters for 4-5 months in hypogean habitats. Winter dormancy is a natural starvation period, providing the opportunity to study autophagy under natural conditions. We aimed to evaluate the autophagic activity in adipocytes and urocytes of the fat body in three time frames: directly before overwintering, in the middle of dormancy, and at its end. For this purpose, we sampled individuals in caves. The cell ultrastructure was studied by transmission electron microscopy (TEM) and the abundance of autophagosomes by immunofluorescence microscopy (IFM), applying the widely used, specific immunolabeling marker microtubule-associated protein 1 light chain 3 (LC3). Before overwintering, TEM revealed scarce autophagosomes and residual bodies in the adipocytes and none in the urocytes. Congruently, IFM showed a very limited or no reaction. In the middle and at the end of overwintering, in both cell types, phagophores, autophagosomes, autolysosomes, and residual bodies were identified by TEM, while LC3 immunolabeling for detecting autophagosomes showed a conspicuous positive reaction. Both methods revealed that there were no significant differences between the sexes in any time frame. Minimal autophagic activity was detected before the winter dormancy, and it gradually intensified till the end of overwintering, probably because reserve proteins in protein granula are not composed of all the required amino acids. We conclude that in T. neglectus, autophagy is a substantial response to starvation and supports homeostatic processes during winter dormancy by supplying cells with nutrients.