Figure 1. Encalypta rhabdocarpa in the alpine region where high-intensity UV light can damage chlorophyll and DNA. Photo by Michael Lüth. Exposure to UV light has been hypothesized as a major deterrent of evolution to land. Both chlorophyll and DNA are easily damaged by high intensities of direct sunlight (Figure 1). In fact, it has been suggested that a major role of lignin, absent in bryophyt...

The rhabdoms of Euphausia superba contain one digitonin-extractable rhodopsin, lambda max 485 nm. The rhodopsin undergoes unusual pH-dependent spectral changes: above neutrality, the absorbance decreases progressively at 485 nm and rises near 370 nm. This change is reversible and appears to reflect an equilibrium between a protonated and an unprotonated form of the rhodopsin Schiff-base linkage...

The Gonioctena nivosa species-group of the genus Gonioctena Chevrolat, 1836 is defined and reviewed. It contains six species including two new to science: Gonioctena gracilicornis (Kraatz, 1879), Gonioctena nivosa (Suffrian, 1851), Gonioctena norvegica (Strand, 1936), Gonioctena springlovae (Bechyně, 1948), Gonioctena amurensis Cho & Borowiec, sp. n. and Gonioctena jani Cho & Borowiec, sp. n. S...

I . An account will be given of the anatomy of the blood-system of Pomatoceros triqueter, and of comparative observations on the following serpulids: Serpula vermicularis, S. lo-biancoi, Hydroides norvegica, Vermiliopsis infundibulum, Salmacina incrustans, Protula intestinum, P. tubularia, Apomatus ampulliferus, A. similis, Spirorbis militaris, and S. corrugatus. 2. In all species there is a ce...

Here we summarize the results from 10 cruises in Chukchi Sea, August, each year 2011 to 2020. Samples for qualitative analysis of microzooplankton were obtained stations located across Sea using a 20μm plankton net. Conditions encountered, terms sea ice coverage and chlorophyll concentrations, varied widely without any obvious relationship with composition assemblage. Examining total 242 sample...

The taxonomic status of Amphinemura palmeni, a rare stonefly from northern Fennoscandia, was re-evaluated in a morphological study combined with analyses of mitochondrial COI and nuclear 28S sequences. Taxon sampling included A. standfussi, with which A. palmeni has been confused, the Nearctic A. linda and seven other Amphinemura species. Amphinemura palmeni is confirmed as a valid species, and...

Two forms of the chitinolytic enzyme N-acetyl-beta-D-glucosaminidase (NAGase, EC 3.2.1.52) have been isolated from the Antarctic krill, Euphausia superba, in order to study their potential role in temperature adaptation processes. A chromatographic protocol was developed that allowed complete separation of the two enzyme forms, named NAGase B and NAGase C. The latter was purified to homogeneity...