Stichopus cf. herrmanni

Another sea cucumber!! This time its from the family Stichopodidae.

I chanced upon it during a recent seagrass monitoring at Pulau Semakau. It has a thick body wall, a lumpy body surface and is covered with orange papillae which contrast brightly against the black body surface.

Following the advice from Dr. David Lane, I proceeded to obtain some tissue samples from the dorsal tegument before returning the creature back to the sea.

After several failed attempts at ossicles preparation from a different species, I decided to try again. And voilà! The beautiful ossicles appeared as I adjusted the microscope’s focus. Intricate tables, C-shaped, S-shaped and branched rods of various patterns came into view. It’s a real wonder that these microscopic skeletons have, over evolutionary time, been reduced to these beautifully elaborate 3-D structures.

Based on the references, the ossicle shapes and general morphology would identify it as a Stichopus sp. and it most resembles Stichopus herrmanni. However none of the references noted S. herrmanni appearing in black. Looks like I’ll have to search deeper into sea cucumber taxonomy.

Sea cucumber ossicles, the real beauty is within.

Pictures taken at: Pulau Semakau, August 2007.


References:

Clark, A. M. & F. W. E. Rowe, 1971. Monograph of the Shallow-Water Indo-West Pacific Echinoderms, British Museum (Natural History), London.

Colin, P. L. & C. Arneson, 1995. Tropical Pacific Invertebrates. A Field Guide to the Marine Invertebrates Occurring on Tropical Pacific Coral Reefs, Seagrass Beds and Mangroves, Coral Reef Press, U.S.A.

Lane, D. J. W. & D. Vandenspiegel, 2003. A Guide to Sea Stars and other Echinoderms of Singapore, Singapore Science Centre, Singapore.

Ictinogomphus decoratus

Most of the commonly seen dragonfly species belong to the family Libellulidae. Some of them have adapted to urbanisation and are thriving very well in the ponds and canals within our landscaped parks and gardens. Dragonflies from the family Gomphidae are less common. They are more sensitive to environmental degradation and thus in Singapore; they are more easily encountered in natural streams and water bodies.

Gomphids' pair of eyes is well separated and this is one of the features differentiating them from other dragonfly families. There are only about eight recorded gomphid species in Singapore. Yangchen spotted this striking Ictinogomphus decoratus during one of our surveys. Ictinogomphus species are large and they like to breed largely in standing water. I. decoratus in particular inhabits ponds and dams which makes them the most common among Singapore’s gomphid dragonflies.

This year we celebrate National Day at Marina Bay. Not many of the spectators would know that the few sedge ponds existing in the nearby Marina South and Marina East would soon be cleared for development. And so we will lose another location which supports good dragonfly diversity.

Pictures taken at: Western part of Singapore, August 2007.


References:

Orr, A. G., 2003. A Guide to the Dragonflies of Borneo. Their Identification and Biology, Natural History Publications (Borneo) Sdn. Bhd, Malaysia.

Orr, A. G., 2005. Dragonflies of Peninsular Malaysia and Singapore, Natural History Publications (Borneo) Sdn. Bhd, Malaysia.