Facebook
Twitter
x
צילום תת מיימי || צלם תת ימי || חגי נתיב
Blog
Portfolio
Archive
All Galleries
Search
Cart
Lightbox
Client Area
Video
About
Contact
Show Navigation
תת ימי
All Galleries
Add to Cart
Download
מאקרו
{ 13 images }
Created 29 Dec 2012
View:
100
|
All
Loading (
)...
Chromodoris annulata-8.JPG
Eurythoe complanata-2.jpg
Flabellina affinis-2.JPG
sea horse- hippocampus14.jpg
Hermit Crab-2.jpg
Portunus pelagicus-blue crab17.jpg
Portunus pelagicus-blue crab28.jpg
מדוזה חוטית נודדת.JPG
HGI_5433.JPG
20120808_5744.JPG
20120808_5649.JPG
Portunus pelagicus-blue crab18.jpg
20120808_5687.JPG
![Portunus pelagicus, also known as the flower crab, blue crab, blue swimmer crab, blue manna crab or sand crab, is a large crab found in the intertidal estuaries of the Indian and Pacific Oceans (Asian coasts) and the Middle-Eastern coast of the Mediterranean Sea. The name "flower crab" is used in east Asian countries while the latter names are used in Australia. The crabs are widely distributed in eastern Africa, Southeast Asia, East Asia, Australia and New Zealand.The males are bright blue in colour with white spots and with characteristically long chelipeds, while the females have a duller green/brown, with a more rounded carapace. The carapace can be up to 20 centimetres (7.9 in) wide.<br />
P. pelagicus commonly enters estuaries for food and shelter. Its life cycle is dependent on estuaries as the larvae and early juveniles use these habitats for growth and development. Prior to hatching, the female moves into shallow marine habitats, releases her eggs and the newly hatched zoea I larvae move into estuaries. During this time they feed on microscopic plankton and progress from the zoea I stage to the zoea IV stage (approximately 8 days) and then to the final larval stage of megalopa (duration of 4-6 days). This larval stage is characterised by having large chelipeds used to catch prey. Once the megalopa metamorphoses to the crab stage they continue to spend time in estuaries which provides a suitable habitat for shelter and food. However, evidence has shown that early juveniles cannot tolerate low salinities for extended periods, which is likely due to its weak hyper-osmoregulatory abilities.[4] This may explain their mass emigration from estuaries to seawater during the rainy season. Male Portunus pelagicus are believed to become more territorial in colder water. This may explain why male crabs are rarely sighted within a close proximity to each other in more temperate waters; it also may explain why their female counterparts seem more prolific in these such areas.](https://archive.hagainativ.com/img-get2/I0000JI5X9g8VKHE/fit=188x188/fill=/g=G0000Jh7PGA3nNEY/I0000JI5X9g8VKHE.jpg)
