In the present study, both lamprey GnRH-I and -III stimulated steroidogenesis and induced ovulation in adult female sea lampreys during their final reproductive stage. One injection of lamprey GnRH-III at 0.1 or 0.2 microg/g lamprey stimulated plasma estradiol levels in lampreys held at each of three water temperatures, 13 degrees , 17 degrees , and 19 degrees , corresponding to increasing stag...

In the pineal organ, two types of ganglion cell exhibit antagonistic chromatic responses to UV and green light, and achromatic responses to visible light. In this study, we histologically characterized UV-sensitive photoreceptor cells that contain a unique non-visual UV pigment, lamprey parapinopsin, in order to elucidate the neural network that is associated with antagonistic chromatic respons...

Welcome to our international conference on rapid sea-level change. While concern about sea-level rise is global, our host country the Islamic Republic of Iran and the neighbouring Caspian countries have a concern of their own. Here, Caspian sea level rose a hundred times as fast as in the world’s oceans. Whereas oceanic sealevel rose 13 centimeter during the whole twentieth century, the Caspian...

A reoccurring conservation problem is the resolution of consumptive use of threatened wildlife and is especially difficult to defend when it occurs for recreational practices. We explored the commercial capture and supply of threatened European river lamprey (Lampetra fluviatilis) to anglers, to determine the extent of exploitation and seek opportunities for improved conservation. The trade beg...

The Black, Azov, Caspian and Aral Seas, remnants of the intracontinental Paratethys basin, are home to a spectacular diversity of crustaceans. This study examines the past history of the Ponto-Caspian fauna through comparative phylogeographical studies on both benthic and planktonic taxa, based on an examination of nucleotide diversity in the mitochondrial, cytochrome c oxidase subunit 1 (COI) ...

Larval sea lamprey inhabit freshwater streams and migrate to oceans or lakes to feed after a radical metamorphosis; subsequently, mature adults return to streams to spawn. Previous observations suggested that lamprey utilize the odor of conspecific larvae to select streams for spawning. Here we report biochemical and electrophysiological evidence that this odor is comprised of two unique bile a...

Thousands of Caspian seals (Phoca caspica) died in the Caspian Sea from April to August 2000. Lesions characteristic of morbillivirus infection were found in tissue specimens from dead seals. Canine distemper virus infection was identified by serologic examination, reverse transcriptase- polymerase chain reaction, and sequencing of selected P gene fragments. These results implicate canine diste...

The Caspian tiger (Panthera tigris virgata) flourished in Central Asian riverine forest systems in a range disjunct from that of other tigers, but was driven to extinction in 1970 prior to a modern molecular evaluation. For over a century naturalists puzzled over the taxonomic validity, placement, and biogeographic origin of this enigmatic animal. Using ancient-DNA (aDNA) methodology, we genera...

The Caspian seal (Pusa caspica) has declined by more than 90% since 1900 and is listed as endangered by IUCN. We made the first quantitative assessment of Caspian seal by-catch mortality in fisheries in the north Caspian Sea by conducting semi-structured interviews in fishing communities along the coasts of Russia (Kalmykia, Dagestan), Kazakhstan and Turkmenistan. We recorded a documented minim...

The sea lamprey (Petromyzon marinus L.) represents one of the two most ancient classes of vertebrates and possesses a functional hypothalamus-pituitary-gonadal axis. However, the presence and functionality of androgens in the sea lamprey remain elusive. Recently, 15alpha-hydroxytestosterone (15alpha-T) has been found in sea lamprey gonads and blood plasma. In this study we examined changes of c...