The aim of the present study was to gain insight into the hydrodynamic characteristics of the relatively simple aquiferous system in specimens of a calcareous syconoid sponge, Urna sp. Data on the morphology and ultrastructure of the sponge combined with measured pumping rates were provided and used for subsequent estimates of the pressure drops of water flow through the aquiferous system. The pumping rates were estimated from...

Demosponges of the genus Halichondria Fleming (1828) are common in coastal marine ecosystems worldwide and have been well-studied over the last decades. As ecologically important filter feeders, Halichondria species represent potentially suitable model organisms to link and fill in existing knowledge gaps in sponge biology, providing important novel insights into the physiology and evolution of the sponge holobiont. Here we re...

The paper aims to elucidate the physico-chemical characteristics of the shell of mangrove horseshoe crabs ( Carcinoscorpius rotundicauda ) and determine the compilation matrix for the first time. The shell composition matrix of C. rotundicauda has never been studied in detail before, especially the shape of the foam, the chemical composition, the functional groups and the mechanical-physical and thermal properties of the shell...

Aim To analyse the importance of climatic and geographical isolation in determining the patterns of speciation and distribution of species within the tardigrade genus Echiniscoides . Location Marine intertidal zone, globally. Methods DNA was extracted from 465 individual tardigrades from 48 localities world‐wide. The tardigrades were divided into clusters using several distance‐based criteria. The phylogeny of these clusters w...

In order to elucidate the evolutionary history and the population structure of the members of the phylum Cycliophora, which live commensally on three species of lobsters, we studied sequence variation in the mitochondrial gene cyctochrome c oxidase subunit I. Overall 242 sequences from 16 locations on both coasts of the North Atlantic, including the North Sea and the Mediterranean, were analysed, revealing 28 haplotypes, with...