The functional response of the phytoseiid predator Chileseius camposi González y Schuster, 1962 (Acarina:Phytoseiidae) on densities of its prey Panonychus ulmi (Koch, 1836) was evaluated under controlled temperature (20 +/- 2 degrees C), relative humidity (75 +/- 15%) and photoperiod (16:8h L:D). A functional type II response was displayed (Holling's disk). Holling, Wolf transformation and Roge...

A new troglobitic spider species, Nesticus dimensis n. sp. (felmale male), inhabiting the Dim Cave of Alanya (Antalya Prov., Turkey) is diagnosed and described. The new species belongs to the Eastern Mediterranean Nesticus Group, which includes N. eremita and N. speluncarum as the most common and widespread species along with N. arenstorffi and N. henderickxi. Evolutionary relationships of the ...

The two-spotted spider mite is a worldwide phytophagous pest displaying a peculiar dispersal. At high density, when plants are exhausted, individuals gather at the plant apex to form a collective silk-ball. This structure can be dispersed by wind or phoresy. Individuals initiating the ball are enclosed in the centre and have a high risk to die. For the first time, the ultimate and proximate mec...

Non-genetic transmission of information across generations, so-called parental effects, can have significant impacts on offspring morphology, physiology, behaviour and life-history traits. In previous experimental work using the two-spotted spider mite Tetranychus urticae Koch, we demonstrated that dispersal distances increase with local density and levels of genetic relatedness. We here show t...

Individuals of the social spider mite Stigmaeopsis longus live communally in narrow, humid nests made from silk threads and display nest sanitation behaviour through the coordinated deposition of faeces. We used artificial dust to experimentally determine that females of this species use silk threads to perform regular cleaning of the nest space and eggs. We first learned that silk-weaving beha...

Dispersal and competition have both been suggested to drive variation in adaptability to a new environment, either positively or negatively. A simultaneous experimental test of both mechanisms is however lacking. Here, we experimentally investigate how population dynamics and local adaptation to a new host plant in a model species, the two-spotted spider mite (Tetranychus urticae), are affected...

The peacock spider, Maratus volans, has one of the most elaborate courtship displays in arthropods. Using regular and high-speed video segments captured in the lab, we provide detailed descriptions of complete male courtship dances. As research on jumping spiders has demonstrated that males of some species produce vibrations concurrently with visual displays, we also used laser vibrometry to un...

Many animals can adjust the sex ratio of their offspring according to their parental ability to invest. In spider mites, larger eggs are likely to be fertilized and produce diploid females, whereas smaller eggs produce haploid males.