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This paper is the first of a series in which more information will be added to the existing on biogeographical distribution of oribatid mites. Here we describe a new species of a phthiracarid mite collected from forest floor litter in southwestern Nigeria. Differences between this species, Atropacarus (Hoplophorella) nigeriensis, and other Hoplophorella species are the foveoli on the aspis and notogaster, the shape of notogastric setae, as well as shapes and chaetotaxy of the genital and anal plates. More differences in taxonomically important features such as the morphological features of the infracapitulum and epimeron as well as leg chaetotaxy between this species and others could not be determined, not only because of lack of information on the latter in literature, but also because many type specimens are not available for dissection which must be done in order to reveal fine morphological details. Atropacarus (Hoplophorella) nigeriensis belongs to the "cucullata" group of Hoplophorella which possess one enlarged adanal seta. It differs from other members of this group in respect of adanoanal and tarsal chaetotaxy. Hoplophorella is considered as a subgenus of Atropacarus in this paper, because there is no evidence in literature that Hoplophorella as a group is a separate phylogenetic entity.
The mesofauna communities were assessed every three months (June 1997 to March 1999), in the litter and soil of a
polyculture system (POA and POC) and from a primary (FLO) and a secondary (SEC) forest. The highest densities were
obtained in POA, due to the dominance of Oribatida. The densities of Acari Oribatida and Collembola were notably lower in
the mineral soil. For non-Oribatid Acari, the same tendency was not clearly detected. In contrary to the other groups, the
highest densities of Collembola were found in FLO. In general, densities in the litter layer were higher. Therefore, strong differences were detected between 1997, an exceptionally dry year caused by the ”EI Niño” Southern Oscillation, and 1998.
The mesofauna population was lowest in 1997 Only in 1997, was the density in FLO, POA and POC higher in the soil fraction. The pattern in SEC was not the same because of the higher amount of litter. We hypothesized that the differences
between 1997 and 1998 were a result of: 1) a reaction of the mesofauna that migrated to the mineral soil during the
extremely dry period of 1997 and 2) a consequence of the litter layer reduction that occurred in 1997, causing lower mesofauna densities. Superimposed on the micro-climatic factors, we observed the influence of the condition of the litter layer on the mesofauna densities. Depending on the physical factors, there are years of high and others with low populations. Extremely wet years could also exert an influence on the soil mesofauna and studies of long-term periods are recommended. Although there was a tendency for the Acari Non-Oribatida biomass estimated in this study to be lower than in temperate forest, the values are however higher than values recorded for many tropical forests. On the contrary, Oribatida
and Collembola biomass were characterized by lower values compared to temperate forests.
An insect inclusion in Upper Cretaceous Burmese amber contained a well preserved flat bug, Archearadus burmensis gen.
n., sp. n., which is described and figured. It is distinguished from all known genera of Aradidae by various characters that
are discussed. A catalogue is given for Aradidae from Amber deposts described to date.
Whip spiders belong to a small arachnid order (Amblypygi) that is not well known. Their most conspicuous feature are
the elongated, extremely thin front legs (“whips“, or antenniform legs). These are no longer used for walking but are modified extremities carrying various sense organs - very much like the antennae of insects. Whereas hundreds of olfactory
hairs are concentrated near the tip of each antenniform leg, large bristles (contact chemoreceptors) are evenly distributed over the entire antenniform leg. The sensory hairs of each antenniform leg contribute about 30,000 small sensory
axons which proceed toward the central nervous system (CNS). The sensory fibers originating from the mechanoreceptive bristles make chemical synapses with a few giant interneurons in the periphery. The giant axons (10-20 pm in diameter) of these large interneurons transmit nerve impulses with a high velocity (6 m/s) to the CNS. The purpose of this fast pathway still needs to be determined. Originally it was thought that the fast giant axons would trigger quick escape reactions, but this was not confirmed in physiological experiments. However, other possible behaviors that may be aided by the giant interneurons are prey capture, fighting, and orientation. What makes whip spiders unique is that both synapses and giant neurons are located far out in the peripheral nervous system. In all other arthropods - except for some arachnids - synapses and giant fiber systems are always found inside the CNS, never in the periphery.
The wolf spider genus Aglaoctenus is revised, and of the 12 original species only two are considered valid: A . castaneus
(Mello-Leitáo) and A. lagotis (Holmberg). Eight specific names are considered junior synonyms of A. lagotis: Porrimosa
granadensis (Keyserling), P. freiburguensis (Keyserling), P. diversa (O.P.-Cambridge), P. obscura (Keyserling), P. glieschi
(Mello-Leitáo), P. callipoda (Mello-Leitáo), Aglaoctenus bifasciatus Tullgren and A. harknessi (Chamberlin). Aglaoctenus
guianensis Caporiacco, described based on an immature specimen from French Guyana is considered species inquirenda
and Porrimosa securifera Tullgren, based on a female specimen from Argentina is transferred to Orinocosa Chamberlin.
The Aglaoctenus species are distributed exclusively in South America, except Chile.
The oligochaetes Dendrodrilus rubidus (intestine/chloragog), Cognettia sphagnetorum (whole specimens), and the gastropod
Arion subfuscus (midgut gland) collected in the Egge Mountains (North Rhine-Westphalia, Germany) accumulated cadmium
(Cd) above the level of that soil horizon they preferably live in. Cd was also detected in the fat body and ovarioles of several
carabid species (Carabus problematicus, Abax parallelipipedus, Pterostichus oblongopunctatus). Seasonal variations were
apparently dependent on the activity and reproduction of the species investigated. In some tissues of field collected Carabus problematicus (intestine, fat body, ovarioles) and of experimentally Cd-stressed Lumbricus terrestris (intestine/chloragog), Enchytraeus albidus (whole specimens), Arion subfuscus (midgut gland), but also in control tissues metallothioneins (MTs) could be detected. These proteins had a low molecular mass (6 to 11 kDa), a high Cd-binding capacity, a considerable amount of cysteine and a higher extinction at 254 nm compared to 280 nm. Cd-stress induced an additional synthesis of these proteins, which was roughly estimated using the cysteine content of the crude MT-fraction.
The beetle fauna of soil and litter in Amazon forest eco-systems was studied by means of Berlese-Tullgren extractions, at 8
sampling dates during 2 years in four experimental plots (one in primary forest, one in secondary forest and two polyculture
plots) of the Embrapa Amazonia Ocidental research centre near Manaus (Brazil). Beetle individuals were found in 99 % of
the extracted litter and soil cores. In total, we recorded 47 beetle families, of which 12 contributed to more than 90% of
the total individual numbers and beetle biomass, respectively. Most individuals recorded were very small averaging less than
2 mm body length. The total number of predator families was low (6 families, 13 %), when compared to that of the decomposers (29 families, 62 %). Only one family was considered herbivorous (Chrysomelidae, 2 %). 28 % of the decomposer families, but 67 % of the predator families ranged among the 12 most abundant beetle families. Among the 12 dominant beetle families the carnivorous Scydmaenidae, Staphylinidae, Carabidae and Pselaphidae represented 51 % of the abundance and 41 % of the biomass. In comparison to other macroarthropods (Chilopoda, Formicidae, Isoptera, Diplopoda)
the contribution of Coleoptera to the total of individual numbers or faunal biomass was rather small. We conclude that
although diversity of the soil dwelling beetles seems to be high, their total contribution to nutrient cycling may be of minor
importance.
The architectural features of the five Nasutitermes species occurring in a Neotropical floodplain (varzea) forest on llha de
Marchantaria in central Amazonia are described: external nest and runway architecture, nest volume, nest height above ground, nesting trees, degree of polycalism). These characteristics are used to build a tentative field key to the nest-building
termite species which should be tested for its usefulness for ecological studies of central Amazonian termites.
Specimens belonging to the Neotropical genus Fauva (Staphylinidae: Osoriinae) were studied from the following collections: Institut Royal des Sciences Naturelles de Belgique, Bruxelles, Belgium (IRSN); Field Museum of Natural History, Chicago, USA (FMNH); and from a collection from Peru, made available by M. Verhaagh (Karlsruhe, Germany). The genus and four species are redescribed and the new species Fauva becki is described. The genus is divided into two species groups and a key to species is provided.
Tooth mesowear analysis on Hippotherium primigenium from the Vallesian Dinotheriensande (Germany)
(2000)
Ein neuer Ansatz zur Rekonstruktion der Paläodiät von Huftieren, die Mesowearmethode, wurde kürzlich von Fortelius &
Solounias (im Druck) beschrieben. Ein großes diagnostisches Potential für die Ernährungsweise von Huftieren wurde in Merkmalen der Zahnabnutzung auf der Okklusalfläche erkannt. Die vorliegende Untersuchung ist in zweifacher Hinsicht der erste Test der Mesowearmethode. (1) Es wird die Diät des hipparionten Equiden Hippotherium primigenium aus
den vallesischen Dinotheriensanden (Rheinhessen, Deutschland) unter Anwendung der Mesowearmethode rekonstruiert.
(2) Um die Robustheit der Methode zu überprüfen, wird eine Blindteststudie durchgeführt, in der die 5 Autoren dieselbe
Sammlung oberer zweiter Molaren unabhängig voneinander untersuchen. Als Konsensusdiät für Hippotherium primigenium,
wird eine gemischte Nahrungszusammensetzung mit Grasanteil, ähnlich der des Impala (Aepyceros melampus) vorgeschlagen. Die Mesowearmethode hat sich als effektiv und robust erwiesen.
Nachweise für Carnivoren-Aktivitäten durch bekaute oder angedaute Knochen sind spärlich überliefert in Lokalitäten des
mittleren und oberen Miozän Europas. In dieser Studie bestimmen wir Skelettelemente aus der obermiozänen Lokalität bei Rudabánya, die durch Carnivoren verändert wurden und diskutieren deren Signifikanz unter Bezug auf ökomorphologische Attribute rezenter Beutegreifer, um auf Muster der Beuteauswahl und Freßverhalten schließen zu können.
Seit über 100 Jahren wurden in Ungarn neogene Suiden gesammelt, doch gibt es darüber bis heute nur wenige Veröffentlichungen. Dieser Beitrag zeigt den derzeitigen Stand der Kenntnisse über die obermiozänen Suiden Ungarns und ihre evolutionären, chronologischen und biogeographischen Verhältnisse zu anderen eurasischen Suiden auf.
In dieser Arbeit beschreiben wir die Skelette und Skelettelemente der Hipparien, die von Jörg und Tobien zwischen 1950
und 1968 in Höwenegg bei Grabungen geborgen worden sind. Diese Fundstelle ist ca. 10,3 Millionen Jahre alt und in ihr sind mehrere fragmentarische aber eben auch vollständige Skelette von Rhinocerotiden, Cerviden, Traguliden, Boviden und insbesondere dem dreizehigen Urpferd Hippotherium primigenium überliefert. Die Beschreibung dieser vollständigen Skelette basiert zunächst auf einer anatomischen Analyse der einzelnen Skelettelemente. Dann werden die Meßwerte der kontinuierlichen Variablen dieser Elemente für die gesamte Höwenegg Population statistisch untersucht, und schließlich die Variabiltät der Ausprägung von 49 Schädel- und Zahnmerkmalen innerhalb dieser Population analysiert. Die Analysen der kontinuierlichen Variablen zeigen im allgemeinen nur eine geringe Streubreite, einige Parameter an den Schneidezähnen und an postcranialen Elementen ausgenommen. Die Verteilung der Merkmalsausprägungen innerhalb des untersuchten Materials zeigt eine weitestgehende Konstanz der Merkmale; geringe Variabilitäten können durch ontogenetische Faktoren erkärt werden. Berücksichtigt man z. B. den Abnutzungsgrad der Kauflächen der Zähne zeigen sich auch schon die meisten Zahnmerkmale allein hinreichend konstant, festzustellen, daß an dieser Fundstelle nur eine einzige Hipparion-Art festgestellt werden kann. Unsere Untersuchungen zeigen, daß das Höwenegg-Pferd nicht nur eines der ältesten Vertreter der Gruppe der Hipparien in Europa war, sondern zudem morphologisch noch äußerst urtümlich ist und stammesgeschichtlich nahe der Basis der Radiation der Hipparien in der Alten Welt steht. Seine Zähne sind noch relativ flachkronig, auf der Oberfläche stark gefaltet und durch tiefe mediolaterale Furchen gekennzeichnet. Dies deutet auf einen nur geringen Gras- und vermehrten Blattanteil in der aufgenommen Nahrung hin. Der Bewegunsapparat zeigt Anpassungen im Bereich der Wirbelsäule sowie der Extremitäten an Sprung- und schnelle Seitwärtsbewegungen. Beides sind notwendige Anpassungen für ein Tier dieser Größe, um in den warm-gemäßigten bis subtropischen mesophytischen Wäldern des mitteleuropäischen Vallesiums und frühen Turoliums überleben zu können.