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libutron:

Sea Apple - Pseudocolochirus violaceus

It may not seem much an apple, nor a cucumber, but these are colorful sea cucumbers commonly known as Sea Apples belonging to the species Pseudocolochirus violaceus (Holothuroidea - Dendrochirotida - Cucumariidae), which occurs in the Indian Ocean and the western part of the Pacific Ocean.

Sea apples are about 18 cm long. They usually are purple, but also can be blue, red, white, and yellow. Three rows of tube feet run along the bottom side of the animal. The top side has two rows of tube feet as well as small scattered tube feet. The body is curved so that the mouth and anus point upward. They have ten tentacles which are bushy purple to red and have white tips. The pieces of the body wall skeleton are rounded, smooth plates with a few holes.

When relaxed, the normal shape is short and sausage-like as with most other sea cucumbers. When stressed, however, it may inflate itself into a large round ball. 

Sea apples live partly hidden to fully exposed with tentacles expanded, even during the day. They feed continuously, capturing large food particles with outstretched branching tentacles that are lightly coated in mucus. 

These beautiful sea cucumbers unfortunately are harvested for the aquarium trade. Ironically, they do not make good aquarium specimens as they are often toxic to their tank mates. 

References: [1] - [2] - [3]

Photo credit: [Top: ©René Cazalens | Locality: Komodo, Indonesia, 2010] - [Bottom: ©Chuck and Jean | Locality: Manila Ocean Park, Philippines, 2008]

alex-does-science
alex-does-science:

What are the FASTEST known Starfish??
(From Echinoblog)
People are always interested in the upper limits of our world. The biggest! The smallest! The most dangerous!Where echinoderms are concerned, I’ve tried to answer a few of these. The biggest starfish can be foundhere.    The largest brittle stars found here. But people always seem a little surprised when they see something like a starfish in motion! Most times, starfish move slowly if at all and so if people see one being the lamborginhi of echinoderms, it generally provokes some curiosity…So, this week a new open access paper by E.M. Montgomery and A.R. Palmer in the Biological Bulletin looks at locomotion in the bat star, Patiria miniata but provides a very handy dandy comparison of movement rates in several well-known sea star species (the paper itself we shall discuss another day….).Why should we care?? Doesn’t this all seem like kind of an…odd thing to know? Indeed. But rate of movement is actually an important bit of information in understanding feeding biology, ecology, and food webs. How fast do the predators go compared to their prey?  How far could an adult travel on its own and disperse its gametes in a discrete amount of time?   So, yeah. Its worthwhile…It should be noted that most of the rates outlined below are based on a clip motivated by predators. So, its not necessarily clear what their “average cruising speed” would be..Some general trends…
(Read more)

alex-does-science:

What are the FASTEST known Starfish??

(From Echinoblog)

People are always interested in the upper limits of our world. The biggest! The smallest! The most dangerous!

Where echinoderms are concerned, I’ve tried to answer a few of these. The biggest starfish can be foundhere   The largest brittle stars found here. 

But people always seem a little surprised when they see something like a starfish in motion! Most times, starfish move slowly if at all and so if people see one being the lamborginhi of echinoderms, it generally provokes some curiosity…

So, this week a new open access paper by E.M. Montgomery and A.R. Palmer in the Biological Bulletin looks at locomotion in the bat star, Patiria miniata but provides a very handy dandy comparison of movement rates in several well-known sea star species (the paper itself we shall discuss another day….).

Why should we care?? Doesn’t this all seem like kind of an…odd thing to know? Indeed. But rate of movement is actually an important bit of information in understanding feeding biology, ecology, and food webs. How fast do the predators go compared to their prey?  How far could an adult travel on its own and disperse its gametes in a discrete amount of time?   So, yeah. Its worthwhile…

It should be noted that most of the rates outlined below are based on a clip motivated by predators. So, its not necessarily clear what their “average cruising speed” would be..

Some general trends…

(Read more)

Fascinating Biology Off the Haitian Coast

While exploring the area off of Haiti, Navassa Island has proved to hold a wide range of interesting sea life. From sea cucumbers and sponges, to multicolored fish, the waters here are teeming with life.

The ROVs have been busy collecting rock, coral, water, and push core samples, and even though this journey may be focused on geology, the biology never ceases to fascinate the scientist. Here are some of the creatures we have seen in the last few dives of the Windward Passage leg of the expedition.

(via: Nautilus Live)

images: Sea Urchin, Anemone, Pelagic Swimming Sea Cucumber, Glass Sponge, and Sea Pig (Ocean Exploration Trust)

Ocean Exploration Trust)
astronomy-to-zoology
astronomy-to-zoology:

Egyptian Sea Star (Gomophia egyptiaca)
…a species of Ophidiasterid sea star which despite its common name is widely distributed throughout the Indo-Pacific (including the Red Sea).  Like other sea stars Gomophia egyptiaca is omnivisrous feeding a range of sessile/slow moving organisms ranging from snails and sponges to algae. 
Classification
Animalia-Echindoermata-Asteroidea-Valvatidae-Ophidiastridae-Gomophia-G. egyptiaca
Image: Alexander Vasenin

astronomy-to-zoology:

Egyptian Sea Star (Gomophia egyptiaca)

…a species of Ophidiasterid sea star which despite its common name is widely distributed throughout the Indo-Pacific (including the Red Sea).  Like other sea stars Gomophia egyptiaca is omnivisrous feeding a range of sessile/slow moving organisms ranging from snails and sponges to algae. 

Classification

Animalia-Echindoermata-Asteroidea-Valvatidae-Ophidiastridae-Gomophia-G. egyptiaca

Image: Alexander Vasenin

libutron
libutron:

Key-hole Sand Dollar - Echinodiscus truncatus
Using its velvet-like covering of small, short spines, the Key-hole Sand Dollar, Echinodiscus truncatus (Clypeasteroida - Astriclypeidae), burrows just beneath the surface of intertidal sands in the Indo-west Pacific waters.
This is a large sand dollar about 8-9cm across, with a pair of elongated holes or lunules close to the disc edge. Various explanations for the adaptive value of the lunules have been put forward. One theory if that the lunule spins assist in burrowing while another ideas is that the holes have a hydrodynamic function in reducing lift in strong currents and thus preventing dislodgment.
Reference: [1]
Photo credit: ©Loh Kok Sheng | Locality: Tanah Merah, Singapore (2008)

libutron:

Key-hole Sand Dollar - Echinodiscus truncatus

Using its velvet-like covering of small, short spines, the Key-hole Sand Dollar, Echinodiscus truncatus (Clypeasteroida - Astriclypeidae), burrows just beneath the surface of intertidal sands in the Indo-west Pacific waters.

This is a large sand dollar about 8-9cm across, with a pair of elongated holes or lunules close to the disc edge. Various explanations for the adaptive value of the lunules have been put forward. One theory if that the lunule spins assist in burrowing while another ideas is that the holes have a hydrodynamic function in reducing lift in strong currents and thus preventing dislodgment.

Reference: [1]

Photo credit: ©Loh Kok Sheng | Locality: Tanah Merah, Singapore (2008)

libutron

libutron:

Peronella lesueuri a beautiful sand dollar of importance in coastal ecosystem processes

The striking Peronella lesueuri (Clypeasteroida - Laganidae), is a large sand dollar up to 15 cm in diameter, with a wide Indo-Pacific distribution. The most noticeable and amazing feature of this species is its bright pink when alive, hence its common name of Pink sand dollar.

It is a shallow burrower and occurs at densities which may influence surface sediment chemistry and community dynamics. Therefore, knowledge of seasonal and diet movement rates and rhythms of this species are a key of interest in understanding coastal sediments biogeochemical dynamics.

References: [1]

Photo credit: ©Loh Kok Sheng | Locality: Pulau Sekudu (Frog Island), off Chek Jawa, Pulau Ubin, Singapore (2009) | [Top] - [Bottom]

Protecting One Fish Could Keep Caribbean Coral Reefs From Disappearing 
by Katie Valentine
Ocean warming poses a major threat to the world’s coal reefs, but with some ocean conservation effort, Caribbean reefs could become far more resilient to this stressor, a new report has found.
The report analyzed thousands of surveys of coral, seaweeds, and grazing fish and sea urchins, and found that the loss of coral grazers such as parrotfish and urchins is one of the most pressing threats facing Caribbean reefs today — so pressing that, if these grazers continue to decline, Caribbean coral reefs could completely disappear in the next 20 years. In fact, the decline of these grazers has driven more degradation of Caribbean coral than ocean warming has over the last 40 years, with 50 percent of Caribbean coral reefs declining since the 1970s…
(read more: TakePart)
photograph by Shutterstock

Protecting One Fish Could Keep Caribbean Coral Reefs From Disappearing 

by Katie Valentine

Ocean warming poses a major threat to the world’s coal reefs, but with some ocean conservation effort, Caribbean reefs could become far more resilient to this stressor, a new report has found.

The report analyzed thousands of surveys of coral, seaweeds, and grazing fish and sea urchins, and found that the loss of coral grazers such as parrotfish and urchins is one of the most pressing threats facing Caribbean reefs today — so pressing that, if these grazers continue to decline, Caribbean coral reefs could completely disappear in the next 20 years. In fact, the decline of these grazers has driven more degradation of Caribbean coral than ocean warming has over the last 40 years, with 50 percent of Caribbean coral reefs declining since the 1970s…

(read more: TakePart)

photograph by Shutterstock

Dying For Fijis Sea Cucumbers

by Amy West

What’s it Worth? Deepening pressure on Fiji’s coral protectors.
Redfish, Greenfish, Blackfish.
Pinkfish, Curryfish, Lollyfish.


They sound like Dr. Seuss characters and certainly look like they should be. Yet these sausage-shaped, rubbery animals stippled in fleshy bumps are not fish at all, but an invertebrate in the group that includes sea stars, sea urchins and sand dollars. Sea cucumbers, referred to as “bêche-de-mer” or “trepang” when sold as dried food, are largely motionless creatures, which is why divers scoop hundreds of them up daily to export to Asia. A single high value individual in Fiji can fetch about $80 US, notes one report.
Sea cucumbers are not a new food craze; the Chinese have eaten them at least since the 1600s and sought this delicacy from Fiji since the early 1800s. Today, the increasing market demand and the push to dive deeper for these invertebrates and start new fisheries in other countries have sent stocks declining worldwide. Some have disappeared locally in Pacific Island nations, and in Fiji, divers are actually dying for them…
(read more: Monga Bay)
photographs by Stacy Jupiter

Scientists zero in on what’s causing starfish die-offs

Starfish are dying by the millions up and down the West Coast, leading scientists to warn of the possibility of localized extinction of some species. As the disease spreads, researchers may be zeroing in on a link between warming waters and the rising starfish body count…

(read more: PBS NewsHour)

Video by Katie Campbell/Earthfix. Laura James also contributed to the video

Monterey Bay Aquarium Research Institute

Our colleague Chris Mah at the Smithsonian’s National Museum of Natural History recently described new species of deep-sea starfish, including one named for MBARI’s ROV Tiburon, which collected the specimen.

Click the link to read more about these new species: http://www.echinoblog.blogspot.com/2014/06/the-hippest-post-you-know-new.html