Pseudocnus lubrica
From ize
Contents |
Taxonomy
| Kingdom: Animalia |
| Phylum: Echinodermata |
| Class: Holothuroidea |
| Order: Dendrochirotida |
| Family: Cucumariidae |
| Genus: Pseudocnus |
| Species: P. lubrica |
Description
A small sea cucumber, ranging from white to dark brown. Some populations have small black specks on the dorsum. Has 2 rows of well developed tube feet on ventral (bottom) side, with more small scattered feet on rest of the body. There are ten feeding tentacles, all of which are the same size. Contains skin ossicles of various shapes, from buttons to pine cones to three-armed ossicles.
Size
Can grow up to 4 centimeters in length
Range
Records of P. lubricus start in southern Alaska and extend down to Cortez Bank, Southern California. Populations in the San Juan Islands as well.
Habitat
Most common from the low intertidal zone to subtidal, aggregating on rock surfaces and algae. Uncommon on Geoduck Beach, may be found on mussel beds.
Misidentification
Often confused with C. curata, C. pseudocurata, and C. piperata. Used to be referred to as Cucumaria fisheri astigmatus (Wells 1924).
Life History
Brooding occurs in large groups during winter months. Breeding happens by males releasing long strands of sperm from genital papillae. Sperm sinks down to aggregations of females below, ready to spawn. Eggs then roll down between tube feet, some floating away in the process. Female reattaches to substratum, brooding eggs until larvae hatch and crawl out. Diet is mostly single-celled algae. No feeding occurs by females between October and March, when brooding is.
Predators
Sand Star (Luidia foliolata), Sunstars (Solaster dawsoni, S. stimpsoni, S. endeca) Leather Star (Dermasteias imbricata) Six-armed Star (Leptarsterias hexactis) Sunflower Star (Pychopodia helianthoides). The Saddle Back Amphipod (Parapleustes) and a small nematode worm have been observed feeding on eggs. Also observed with the parasitic gastropod Thyonicola mortenseni.
Interesting Behavior
Attaches shell and other debris to dorsal surface, presumably as camoflauge.
References
- Lambert, P. 1997. Sea Cucumbers of British Columbia, Southeast Alaska, and Puget Sound. UCB Press Vancouver, BC.
- Kozloff E.N. 1993. Marine Invertebrates of the Pacific Northwest. University of Washington Press. Seattle, Washington
- Nybakken, J., Diversity of the invertebrates: A labratory manual, Pacific Coast version McGraw-Hill ISBN 0697151204
