Systematic study of the closely related hemiurid genera Mitrostoma, Neopisthadena and Opisthadena revealed that Opisthadena cortesi is a junior synonym of Opisthadena dimidia and Opisthadena fujianensis and Opisthadena marina are species inquirendae. Phylogenetic analysis of the 7 recognized species, based on 21 transformation series derived from comparative morphologic characters, produced a s...

This study is the first attempt to survey the diversity of fish digeneans in the Gulf of Gabes (southern coast of Tunisia). A total of 779 fishes belonging to 32 species were sampled. 53 species of Digenea belonging to 15 families were recorded. Among these species, 24 are reported for the first time from the coast of Tunisia. We report one new host record, Lecithochirium sp. from Sardinella au...

The phylogenetic analysis of the 16 recognized genera in the Bunocotylinae, based upon 30 morphological transformation series, produced 2 most parsimonious trees, each with a consistency index of 0.62. The monophyly of the group is supported by 6 synapomorphies. Ahemiurus, Aphanuroides, Aphanurus, Myosaccium, and Indoderogenes separate independently in the basal part of the tree. Saturnius and ...

The motile, unicellular green alga Heamatococcus has come into prominence in recent years as a possible candidate for mass production for its red pigment, astaxanthin. The present paper summarizes the available information on nomenclature, taxonomy, morphology, life cycle and ultra-structure, which have so far been left out of the many reviews on this interesting alga.

Optimal feeding is often constrained by predation avoidance, which may direct feeding to take place on more sheltered, but less profitable, parts of the habitat. Though constrained, feeding preferences and/or digestive capabilities should coevolve with the energetic and nutritional needs of the animal. These needs, as well as risk taking for these goals, may differ between the sexes. We studied...

Predator – prey interactions are often highly co-evolved, with selection over time for prey with morphological and behavioral traits that minimize predation risk. Consequently, in many environments prey choose among potential habitats according to their refuge value. It is unclear, however, when presented with new habitats, if prey are able to evaluate the predation risk of these relative to fa...

Studies on toxicities and tolerances of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) in the brown alga Isochrysis galbana and in the green-lipped mussel Perna viridis were conducted by short-term bioassays using endpoints growth production and mortality, respectively. The 5-day EC(50) and 24-h LC(50) of these heavy metals were determined in the brown alga and mussel, respectively. The EC(...

Trebouxia aggregata (Archibald) Gärtner (phylum Chlorophyta, family Trebouxiaceae), a lichen symbiotic alga, has been identified as host of the well-known herbaceous plant virus Cauliflower mosaic virus (CaMV, family Caulimoviridae). The alga had been isolated from Xanthoria parietina more than 70 years ago and has been maintained in a collection since that time. The CaMV detected in this colle...

Microscopic algae are tougher than you might think. Some can even survive the extreme cold. In this article, we describe one of coolest all, Antarctic green alga called Chlamydomonas sp. UWO241. This one-celled super-organism lives deep in frigid waters a remote and permanently ice-covered lake Antarctica. How does little thrive such barren unwelcoming place? Well, dive into article to learn ho...

Very few studies have analysed the niches of pelagic protist in details. This is because for most protists, both an accurate species definition and methods for routine detection and quantification of cells are lacking. The morphospecies Micromonas pusilla, a marine unicellular green alga, is the most ubiquitous and cosmopolitan picoeukaryote described to date. This species comprises several ind...