Updates on the FixatorFacilitating the investigation, mounting, and photography of structures and specimens in liquid.

N/A.

The Fixator-A simple method for mounting of arthropod specimens and photography of complex structures in liquid.

Mounting and preparing arthropods in liquids for photography and further investigations is a challenging task and may lead to unsatisfactory results and, in the worst case, to damage to specimens. A new method is presented here, which allows the fixation of specimens of different sizes under various degrees of pressure. The method is illustrated by three case studies from different groups of insects and arachnids.

Tarantula phylogenomics: A robust phylogeny of deep theraphosid clades inferred from transcriptome data sheds light on the prickly issue of urticating setae evolution.

Mygalomorph spiders of the family Theraphosidae, known to the broader public as tarantulas, are among the most recognizable arachnids on earth due to their large size and widespread distribution. Their use of urticating setae is a notable adaptation that has evolved exclusively in certain New World theraphosids. Thus far, the evolutionary history of Theraphosidae remains poorly understood; theraphosid systematics still largely relies on morphological datasets, which suffer from high degrees of homoplasy, and traditional Sanger sequencing of preselected genes failed to provide strong support for supra-generic clades.

The toxicity of the three antifouling biocides DCOIT, TPBP and medetomidine to the marine pelagic copepod Acartia tonsa.

Copepods, the largest group of pelagic grazers, are at risk from exposure to antifouling biocides. This study investigated the toxicity of the antifouling biocides 4,5-dichloro-2-octyl-1,2-thiazol-3(2H)-one (DCOIT), triphenylborane pyridine (TPBP) and 4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole (medetomidine) to the copepod Acartia tonsa, using mortality and egg production as endpoints. The toxicity ranking for mortality was as follows: DCOIT (LC50 57 nmol l(-1)) = TPBP (LC50 56 nmol l(-1)) > medetomidine (LC50 241 nmol l(-1)).