The chorionic structure of sixteen pentatomid species is described. Morphological patterns in different taxonomic levels are discussed. In addition, egg characters useful in cladistic analyses are listed, and some of those characters are tested for congruence with two cladistic analyses previously conducted within Pentatomidae. Descriptive studies were conducted with Banasa induta, Capivaccius ...

fecundity is one of the important indicators of reproduction biology in fishes especially in rearing and restocking management of endangered species such as sturgeon. the fecundity of stellate sturgeon (acipenser stellatus pallas, 1771) was studied in 50 specimens captured by gill net (mesh size= 100 mm) and seine net in different fishing areas along the southeastern part of the caspian sea fro...

A morphological study with the use of scanning electron microscope of 67 species of Iberian Lycaenidae is presented. The study covers all the genera present in the area and shows an extraordinary variation in chorionic characters that allows egg diagnosis for most species. A morphometric study showed that the eggs from the sample have sizes that are correlated with adult size, but some species ...

Nearly simultaneous fertilization of an egg by two or more sperm (polyspermy) is a lethal condition in most organisms. Sperm competing for an egg face opposing selective pressures. The race to fertilize favours rapid penetration of the egg’s outer protective layer; a close finish between two sperm leads to polyspermy and death. Under most conditions of sperm competition, selection favours maxim...

Organisms with external fertilization are often sperm limited, and in echinoids, larger eggs have a higher probability of fertilization than smaller eggs. This difference is thought to be a result of the more frequent sperm-egg collisions experienced by larger targets. Here we report how two components of egg target size, the egg cell and jelly coat, contributed to fertilization success in a se...

1830 egg-larvae of 7 species belonging to long palped crane flies (Tipulidae): Ctenophora guttata Meigen, Nephrotoma pratensis Linnaeus, N. dorsalis Fabricius, N. scurra Meigen, N. flavescens Linnaeus, N. submaculosa Edwards and N. crocata Linnaeus were obtained from 22 females captured in Lithuania in 2011-2012. It took from five days to more than three weeks for eggs to hatch. Crane flies hav...