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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.
The collection of the Museo de Paleontología de Guadalajara, Jalisco, Mexico (MPG) contains fossils of vertebrates from
several localities in the State Jalisco, SW-Mexico. The localities are Miocene up to Pleistocene in age. Based on investigations during a visit at the MPG in 2003 a faunal list and a short characterisation of the faunal assemblage are presented in
comparison to the localities Rancho la Brea (California, USA) and Mina (Nuevo León, NE-Mexico). Potential projects for further investigations on the fossil material and the localities are proposed.