Discrimination of millipedes by the opossum Didelphis albiventris (Marsupialia, Didelphidae)

Millipedes are toxic preys for many vertebrates. Two individuals of the opossum species D. albiventris were videorecorded when feeding on the millipedes G. olivaceus and L. dentellus. Data were compared with feeding behavior on Tenebrio larvae. The opossums are resistant to intoxication by millipedes. Although chemical defenses of the millipedes were not effective against the opossum predation, they make them less attractive.

THAUMATOMYRMEX STRIPS MILLIPEDES FOR PREY - A NOVEL PREDATORY BEHAVIOR IN ANTS, AND THE 1ST CASE OF SYMPATRY IN THE GENUS (HYMENOPTERA, FORMICIDAE)

We describe, for the first time, the predatory behaviour of Thaumatomyrmex ants on millipedes of the family Polyxenidae, based on field observations of T. atrox and a field and laboratory study of T. contumax. The capture of the prey and the removal process of its body-covering setae by the ants before they eat the millipede are described. This specialized behaviour in at least two species of the genus, belonging to two distinct groups of species, indicates a general trend in Thaumatomyrmex. We coupled this study with a comparative morphological analysis of the mouthparts and digestive tube of these and other Thaumatomyrmex species. Also, we report the first case of sympatry in the genus, which suggests that Thaumatomyrmex includes several species. and not only one highly variable taxon, as hypothesized earlier.

Swarming of millipedes, a new case noticed in the District of Patrocinio-MG-Brazil

A population boom of the millipede Plusioporus setigerhas been recorded in coffee crops in the district of Patrocinio-MG, Brazil on the last five years. The millipedes spread over dwelling houses and to vegetable gardens, orchards and small plantations. It was suggested that population increase occurred as a consequence of the organic materials in high scale and also periodic irrigation in the coffee crop.

Effects of deltamethrin pyrethroid on the respiratory metabolism of the neotropical spirostreptid millipedes Gymnostreptus olivaceus and Plusioporus setiger

The effects of deltamethrin on the respiratory metabolism of Gymnostreptus olivaceus and Plusioporus setiger were investigated. Acetone solutions corresponding to half the LD50 values, i.e., 20 μg.g-1g for G. olivaceus and 4.40 μg.g-1 for P. setiger, were used. Metabolism was determined with a Warburg respirometer at 25°C. Respirometric measurements were performed 1, 3 and 6 hours after administration of the pyrethroid to the same groups of millipedes. After 24 hours, daily respirometric measurements lasting 1 hour each were made on different millipede groups for a period of 10 days. Significant differences were detected only between the groups treated with the pyrethroid and the two control groups. In G. olivaceus, respiratory rates increased by about 1.65-fold compared to normal immediately after administration of the pyrethroid, followed by a gradual decrease up to 72 hours and a return to normal levels thereafter. In P. setiger the increase was about 1.1-fold compared to normal, with a decrease up to 96 hours and a return to normal thereafter. Although increased oxygen consumption was observed, a detoxification process occurred in both species, so that the possible metabolism of the pyrethroid may justify the low toxicity of deltamethrin for G. olivaceus and P. setiger.

Bipedal Locomotion: A Fractional CPG for Generating Patterns

Proceedings of the 10th Conference on Dynamical Systems Theory and Applications

Tropical dermatology: Venomous arthropods and human skin Part II. Diplopoda, Chilopoda, and Arachnida

Members of arthropod classes Chilopoda (centipedes), Diplopoda (millipedes), and Arachnida (spiders and scorpions) cause tissue injury via bites, stings, and/or a release of toxins. A few members of the Acari subclass of Arachnida (mites and ticks) can transmit a variety of infectious diseases, but this review will cover the noninfectious manifestations of these vectors. Dermatologists should be familiar with the injuries caused by these arthropods in order to initiate proper treatment and recommend effective preventative measures. (J Am Acad Dermatol 2012;67:347.e1-9.)

Presence of calcium in oocytes of the diplopod Rhinocricus padbergi Verhoeff (Spirobolida, Rhinocricidae)

In diplopods, the presence of calcium-containing structures seems to be a common finding in some species, with its formation being similar to that observed for other intracellular mineralization systems. In the present study, using histochemistry and transmission electron microscopy, a large amount of calcium was observed in the oocytes of Rhinocricus padbergi. Calcium was detected in both less and well developed oocytes, i.e., the occurrence of calcium coincided with the beginning of vitellogenesis. Calcium was observed as fine granulation distributed within the cytoplasm or deposited in spherical structures apparently formed by overlapping calcium layers. Some authors have suggested that these structures represent a type of reserve used for the calcification of the embryo exoskeleton, whereas others believe that calcium inclusions are a mechanism of organism detoxification as a result of excess calcium ingested by animals during soil turnover. We suggest in this paper that the first hypothesis could be occurring in R. padbergi since at the juvenile stages of the individuals the uptake of calcium is low and because the oocyte is a specialized cell not associated with detoxification.

Histochemical studies of Rhinocricus padbergi Verhoeff ovaries (Diplopoda, Spirobolida, Rhinocricidae)

Histochemical studies of Rhinocricus padbergi Verhoeff ovaries demonstrated that the oocytes contained lipids, proteins and polysaccharides. The probable synthesis site of each is considered, and the origin and function of the Ca found is discussed.

Sewage sludge toxicity in edaphic organism: Analysis of midgut responses in the diplopod Rhinocricus padbergi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ultrastructural Alterations in the Midgut of Diplopods after Subchronic Exposure to Substrate Containing Sewage Mud

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cytogenetics of four species of Spirostreptidae (Diplopoda, Spirostreptida)

Considering an estimated number of millipedes of approximately 80,000, cytogenetic studies on these animals are rare, as only a total of 70 species have their karyotypes described. The present study reports on the chromosomal number of four Brazilian diplopods of the family Spirostreptidae: Urostreptus atrobrunneus with 2n = 24, XY; Gymnostreptus olivaceus 2n = 12, XY and Alloporus araraquarensis and A. principes, 2n = 18, XY. The C-banding pattern and NOR staining of U. atrobrunneus, G. olivaceus and A. araraquarensis are described. (C) 2008 Elsevier Ltd. All rights reserved.

Comparative cytogenetics in different populations of the cavernicolous diplopod Pseudonannolene strinatii (Diplopoda, Pseudonannolenidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Description of a new species and the karyotype of the cavernicolous millipede Pseudonannolene Silvestri and the karyotype of Pseudonannolene strinatti Mauriès (Diplopoda, Pseudonannolenida, Pseudonannolenidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)