Three new species of Pseudosympycnus Robinson are described and illustrated from Peru: P. pennipes sp. nov., latitarsus nov. rafaeli In addition, latipes (Parent) is recorded for the first time country male terminalia illustrated. The photographs holotype bicolor an updated key to genus provided.

A germ-cell specific organelle, nuage, in Oryzias latipes is polymorphic. Nuages with a strand-like structure and amorphous fibrous bodies can be discriminated from each other; furthermore 2 types of nuages of intermediate morphology are also present. After the administration of puromycin or actinomycin D, nuage morphology in spermatogonia was examined by electron microscopy. Puromycin as well ...

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are thought to be the result of a gene duplication event early in vertebrate evolution. To learn more about the evolution of these enzymes, we expressed in vitro, characterized, and modeled a recombinant cholinesterase (ChE) from a teleost, the medaka Oryzias latipes. In addition to AChE, O. latipes has a ChE that is different from ei...

Chromosomes and detailed karyotype information (the number, shape, relative length, arm ratio, centromeric index) of Callimenus (=Bradyporus) macrogaster macrogaster Lef. (Orthoptera: Tettigonioidea, Bradyporini) of Turkey belonging to the subfamily Bradyporinae are described. The diploid number of chromosomes was found to be 2n male symbol = 23, with 2 metacentric pairs, 2 submetacentric pairs...

The objective of this study was to find and validate estrogen-related biomarkers from plasma proteins in Oryzias latipes after exposure to an estrogen disrupting compound, α-endosulfan. The acute toxicity of α-endosulfan on O. latipes after 96 h of exposure was 13.72, 16.18, and 22.18 μg L(-1) for the LC10, LC20, and LC50 values, respectively. To confirm estrogenic disturbance by α-endosulfan, ...

The Hong Kong-originated medaka fish Oryzias curvinotus expresses nine genes (OcGC1 approximately OcGC8 and OcGC-R2) for membrane guanylyl cyclases (membrane GCs) and three genes (OcGCS-alpha(1), OcGCS-alpha(2), and OcGCS-beta(1)) for soluble GC subunits. The deduced amino acid sequences of membrane GCs expressed in O. curvinotus were quite similar to those expressed in the Japanese medaka Oryz...

In order to monitor the developmental features of embryos, larvae, and juveniles of Oryzias latipes (Temminck and Schlegel), Oryzias latipes was caught in river of Shinduck-dong, Yeosu-si, Jeollanam-do, on May 2011, and experiments were carried out in Ichthyology laboratory at Chonnam National University. The blastodisc step was the first level for natural spawning. The optic vesicle, Kupffer's...

Sex chromosomes and the sex-determining (SD) gene are variable in vertebrates. In particular, medaka fishes in the genus Oryzias show an extremely large diversity in sex chromosomes and the SD gene, providing a good model to study the evolutionary process by which they turnover. Here, we investigated the sex determination system and sex chromosomes in six celebensis group species. Our sex-linka...