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Keywords: zoologija, nove najdbe, Neuroptera, Deleproctophylla, Albanija, zoology, new record, Neuroptera, Deleproctophylla, Albania
Published in DKUM: 21.12.2015; Views: 1117; Downloads: 44
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Abstract: The occurrence of the wormlion species Vermileo vermileo (Linneeus, 1758) is confirmed for the Mediterranean region of Slovenia and Croatia. Its predatory larvae were found in substrates consisting of fine sand or powder, where they construct pitfall traps similar to those of antlions. Wormlion larvae were reared in laboratory to study their biology.
Keywords: zoologija, dvokrilci, volkci, črvasti volkec, Vermileo, Slovenija, Hrvaška, zoology, Diptera, wormlions, Vermileo, Slovenia, Croatia
Published in DKUM: 10.07.2015; Views: 1659; Downloads: 32
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Abstract: Morphology and behaviour of third instar larvae of the Holomediterranean antlion species Myrmecaelurus trigrammus (Pallas) are described. Larvae are facultative pit-builders, they either ambush their prey at the surface, or dig pitfall traps that prey fall in to. Dark brown spots on dorsal and ventral sides of the head and on dorsal side of the thorax are charac-teristic of the larvae. Eye tubercles are not prominent. Jaws are equipped with long bristles, campaniform sensilla, sensilla coeloconica, and digitiform sensilla. A unique feature is the shape of the tips of all three teeth that is screw-like with a polyhedral surface. The body surface is covered with longitudinally grooved bristles and plumose hairs. On the tip of the antennae and on terminal and subterminal parts of labial palps sensilla basiconica occur. On the 9th abdominal segment there are two bulges, each of them bearing four digging bristles. Non-prominent eye tubercles and numerous mandibular bristles are morphological traits of pit-builders. Most of the behavioural traits are related to pit builders, whereas forward movement, waiting for prey without a pit and frequent changing of ambush location are traits of non-pit builders.
Keywords: zoologija, volkci, morfologija, Neuroptera, zoology, antlions, morphology, Neuroptera
Published in DKUM: 10.07.2015; Views: 1838; Downloads: 104
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Abstract: In this case study we present an application of different analytical electron microscopic methods in biology, to elucidate their usefulness in such investigations. Using analytical electron microscopy, spherites in the digestive gland cells of the helicid snail Chilostoma lefeburiana were examined at three stages: just before the non-feeding period of over-wintering in November, in the middle of over-wintering in February and at its end in March. A detailed characterization of changes in the elemental composition of the spherites was characterized by a combination of transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDXS), electron energy-loss spectroscopy (EELS) and energy filtering TEM (EFTEM). During over-wintering, the spherites passed the following changes. Before over-wintering in November, they consisted of striking concentric layers of electron-dense and electron-lucent zones, while in February and March they showed clear empty zones between materials of different electron density. In November spherites, C, O, Ca, P, Cl, Fe, Si, Na, K, Mg and S were detected, whereas in February ones C, O, N, Cl, Si and S were found and only C, O, N, Si and Cl were detected in March spherites. It is suggested that the elements missing in February and March were used in different physiological processes during over-wintering, like (1) the maintenance of the appropriate elemental composition of the internal environment, (2) accumulation of non-toxic waste materials that cannot be metabolized and (3) avoiding potential intoxication by contamination with toxic metals.
Keywords: zoology, Chilostoma lefeburiana, snails, digestive gland, over-wintering, spherites, elemental analyses, environmental pollution, chemical structures
Published in DKUM: 07.06.2012; Views: 1912; Downloads: 97
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Abstract: Periodical changes in the structure of spherites in the Malpighian tubule cells of the cave cricket Troglophilus neglectus were studied to elucidate their role during the cricket's life cycle in natural circumstances. Special interest was given to the dormant overwintering period when we hypothesized that the primary role of spherites is to supply minerals for basic vital processes. The investigation was carried out by light and transmission electron microscopy, energy dispersive X-ray spectroscopy, electron energy-loss spectroscopy and energy-filtering TEM. Spherites are present only in the middle Malpighian tubule segment, consisting of Type 1 cells, characterized, among other features, by a round, apically placed nucleus and numerous spherites, and a few Type 2 cells with an elongated nucleus in the centre and sparse spherites. At the beginning of dormancy in November juveniles, minerals are accumulated in spherites and then decline until March.In one-year-old May larvae, spherites are commonly rich in minerals, and from July onwards they are progressively exploited in the adults. Spherite destruction starts with apoptosis in senile October individuals. The findings suggest that the mineral supply of spherites in Malpighian tubules is crucial to supporting vital processes throughout the life cycle of T. neglectus.
Keywords: biology, zoology, cells, spherites, insects, Troglophilus neglectus, analysis
Published in DKUM: 07.06.2012; Views: 2162; Downloads: 99
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