Previously, the evolution of gills was thought to have occurred through two diverging lines: gills formed from the endoderm, as seen in jawless fish species, or those form by the ectoderm, as seen in jawed fish. (wikipedia.org)
Species4
Previously, the evolution of gills was thought to have occurred through two diverging lines: gills formed from the endoderm, as seen in jawless fish species, or those form by the ectoderm, as seen in jawed fish. (wikipedia.org)
The examination of morphological characters revealed that this new species is similar to P. siamensis (Oka, 1917), a common turtle leech species found in Thailand. (pensoft.net)
This study presents the first report of the use of a combination of morphological and molecular techniques to describe a new leech species that parasitizes Asian leaf turtles, Cyclemys dentata (Gray, 1831) and dark-bellied leaf turtles, C. enigmatica Fritz et al. (pensoft.net)
Leech specimens were collected from two different turtle species at six different collecting sites. (pensoft.net)
Lower1
The concentration of oxygen in water is lower than air and it diffuses more slowly. (wikipedia.org)
Water7
These filaments have many functions including the transfer of ions and water, as well as the exchange of oxygen, carbon dioxide, acids and ammonia. (wikipedia.org)
Fish exchange gases by pulling oxygen-rich water through their mouths and pumping it over their gills. (wikipedia.org)
The gills push the oxygen-poor water out through openings in the sides of the pharynx. (wikipedia.org)
The high surface area is crucial to the gas exchange of aquatic organisms as water contains only a small fraction of the dissolved oxygen that air does. (wikipedia.org)
Oxygen has a diffusion rate in air 10,000 times greater than in water. (wikipedia.org)
The use of sac-like lungs to remove oxygen from water would not be efficient enough to sustain life. (wikipedia.org)
Additionally, habitat preferences tended toward low oxygen conditions such as puddles or water patches on rubber plantations. (pensoft.net)