Hormonal control of oocyte maturation in crustaceans is reviewed. The bihormonal control of egg maturation is accomplished by the inhibitory neuropeptides originating in the X-organ/sinus gland neurosecretory system and a host of stimulatory hormonal factors secreted from various sources. Among the gonad stimulatory hormones, steroids play a pivotal role in the control of molting and reproducti...

Aquatic pollution has led to the accumulation of various xenobiotics in crustaceans. A number of these environmental chemicals have been found to interfere with molting of crustaceans. Results of initial mechanistic studies with Uca pugilator suggest that the disruption of molting results from the disturbance to the Y-organ-ecdysteroid receptor (EcR) axis by xenobiotics. Such disturbance to the...

The evolutionary relationships of the onychophorans (velvet worms) and the monophyly of the arthropods have generated considerable debate. Cladistic analyses of 12S ribosomal RNA sequences indicate that arthropods are monophyletic and include the onychophorans. Maximum parsimony analyses and monophyly testing within arthropods indicate that myriapods (millipedes and centipedes) form a sister gr...

Our study was a biological evaluation of soil contamination near a non-operating pesticide tomb. The soil contaminated with pesticides had a negative effect on the growth of crustaceans such as Heterocypris incogruens (Ostracodtoxkit test) and the development of plants such as Lepidium sativum, Sinapis alba, and Sorghum saccharatum (Phytotoxkit test). This adverse effect persisted up to 5 years...

What is a stomatopod? Stomatopod crustaceans are commonly known as mantis shrimp, because their preycatching (raptorial) appendages resemble those of praying mantises. They are strictly marine and are quite distinctive from all other crustaceans, having separated from them roughly 400 million years ago and having evolved on their own unique track ever since. About 500 species are recognized tod...

Using a database that includes nearly half (46%) of the estimated 68,000 described species of extant crustaceans, as well as the names of the authors who described each species and the date of description, we plotted the number of species described vs. year of description to examine rates of, and trends in, crustacean species descriptions over time. Plots were generated for all crustaceans and ...

Transposable elements are major constituents of eukaryote genomes and have a great impact on genome structure and stability. They can contribute to the genetic diversity and evolution of organisms. Knowledge of their distribution among several genomes is an essential condition to study their dynamics and to better understand their role in species evolution. LTR-retrotransposons have been report...