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In this paper, we describe a new species of Mesoplophora collected from forest floor litter in southwestern Nigeria. Mesoplophora is a cosmopolitan genus of pytchoid mites that has been recorded from the Palaearctic region as well as Morocco
and Tchad in the Ethiopian region. M. ife an a is the first Mesoplophora species to be fully identified and described from Nigeria. Differences between this species, M. ifeana, and other Mesoplophora species recorded from Africa are observed in
respect of the number of spines on the sensillus, presence of two pairs of exobothridial setae and leg chaetotaxy. The lack of information on fine taxonomic details of adults and deutonymphs of M. africana from Tchad as well as the discrepancies in the description of certain morphological features such as organisation and chaetotaxy of the ventral plates as well as the nomenclature of setae on the aspis were noted. Attention was drawn to the unique combination of traits of both lower
and higher Oribatida in Mesoplophora, a trait which may be responsible for its ubiquitous distribution.
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.
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 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.
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.
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.
We present a species list of spiders collected over a period of more than 5 years in a rainforest reserve in central Amazonia
-Reserva Ducke. The list is mainly based on intense sampling by several methods during two years and frequent visual
sampling during 5 years, but also includes records from other arachnologists and from the literature, in total containing 506
(morpho-)specles in 284 genera and 56 families. The species records from this Neotropical rainforest form the basis for a
biodiversity database for Amazonian spiders with specimens from several Brazilian collections and the collection of the
State Museum of Natural History Karlsruhe, where it is housed. This database will in the future facilitate species identification of Neotropical spider collections, allow comparison of morphospecles and serve as an important background for biodiversity evaluation in natural and anthropogenic habitats and the recognition of species distribution and loss. For further evaluation of the structure of Neotropical spider assemblages and their ecological function we present an analysis of the guild structure of the fauna of Reserva Ducke, although we also emphasize the lack of knowledge on natural history and behavior for many of the species.
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.