Holothuria difficilis
From Wikipedia, the free encyclopedia
| Holothuria difficilis | |
|---|---|
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Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Holothuroidea |
| Order: | Holothuriida |
| Family: | Holothuriidae |
| Genus: | Holothuria |
| Species: | H. difficilis |
| Binomial name | |
| Holothuria difficilis Semper, 1868 | |
Holothuria (Platyperona) difficilis is a species of sea cucumber in the family Holothuriidae.[2] Holothuria comes from Latin but is originally taken from Greek. Its meaning is a plantlike animal whose origin is uncertain,[3] while the German zoologist Hubert Ludwig proposed that it may mean "sea penis," since the root θούριος (thoúrios) has the connotation "sexually arousing."[4]
H. difficilis is a member of the phylum Echinodermata meaning they share a general body plan with other members of the phylum. These traits include pentamerous radial symmetry, an endoskeleton, an oral side opposite of an aboral side, a water vascular system, and tube feet.[5] The oral side contains the mouth for feeding and the aboral side contains an anus used to rid of waste and for respiration. Tube feet is used for locomotion. H. difficilis also contains several mechanisms for defense. Structurally, their dermis is noxious and they also contain very thin Cuvierian tubules that can be ejected.[6] It has been hypothesized these defense mechanisms, that animals such as Holothurians have, are due to evolution against predation.[7] This species contains one gonad and can perform sexual reproduction.[8]
Distribution and habitat
The species has been found in many seas and oceans across the globe such as the Red Sea, and near Central America.[2] However, its general distribution is in the Indian and Pacific Oceans.[2][1] Typically, this species is benthic and lives inshore.[2] When observed in La Reunion Island fringing reefs, the species resided in outer reef flats and under large boulders.[9]
