Impatient Sea Cucumber, Holothuria (Thymiosycia) impatiens

Impatient Sea Cucumber, Holothuria impatiens. Sea Cucumber collected from a tidal pool in the greater Los Cabos area, Baja California Sur, January 2016. Length: 15 cm (5.9 inches).

Impatient Sea Cucumber, Holothuria impatiens. Sea Cucumber collected from a tidal pool in the greater Los Cabos area, Baja California Sur, February 2017. Length: 16 cm (6.3 inches). Identification courtesy of Bob Hillis, Ivins, Utah.

Impatient Sea Cucumber, Holothuria impatiens. Underwater photography taken in the greater Los Cabos area, Baja California Sur, October 2019. Photograph courtesy of Bob Hillis, Ivins, Utah.

Phylogeny:  The Impatient Sea Cucumber, Holothuria (Thymiosycia) impatiens   (Forsskål, 1775), is a member of the Holothuriidae family of sea cucumbers. The genus Holothuria is one of five genera in this family. There are about one hudred and sixty species in this genus, fifteen of which are within the subgenus Thymiosycia. This species is also known as the Brown-spotted Sea Cucumber or Bottleneck Sea Cucumber. In Mexico this species is called Pepino de Mar Manchas Pardas. There are currently no accepted subspecies or varieties of this species.

Morphology:  Impatient Sea Cucumbers have a slender, conical, or bottle-shaped, body. The mouth is located at the narrow end on the body. The mouth is encircled by twenty short, white, tentacles, though they are often retracted from view. The exterior is covered with conical protuberances of varying height. Impatient Sea Cucumbers may be whitish, gray, brown, or reddish in color. There are usually 5 to 7 darker bands around the narrow part of the body. This species reaches at least 16.2 cm (6.5 inches) in length. Some sources extend this to 25 cm (9.8 inches) in length.

Habitat and Distribution:  During the day the Impatient Sea Cucumbers are usually found hiding in caves and crevasses of the reef, under coral rubble, or between boulders. At night they extend their bodies over sandy substrates to feed. They are found from the lower intertidal zone to depths of 67 m (220 feet). They may be found in lagoons, reef flats, or open water. Impatient Sea Cucumbers are nearly circumtropical in distribution. They are found on both coasts of Mexico, in the Caribbean, Gulf of Mexico, Gulf of California, and the Pacific Ocean, south of Bahia Rosario, Baja California.

Diet:  Impatient Sea Cucumbers are detritivores. They ingest sea floor sediment and digest the organic matter. The remaining sand and non-digestible matter is expelled.

Predators:   Impatient Sea Cucumbers can expel sticky white filaments from their Cuvier’s glands. These filaments distract, confuse, and entangle potential predators. Even with this defense mechanism they are still prey for anemones, crabs, fish, gastropods, octopuses, sea stars, and shore birds.

Reproduction:  Impatient Sea Cucumbers are gonochoristic (male or female for life). They reproduce sexually through broadcast spawning, with external fertilization. The gametes form planktonic larva. The larva pass through several phases over a two month period. After this time they settle to the bottom to begin their benthic life.

Ecosystem Interactions:  Impatient Sea Cucumbers engaging in any types of parasitic, commensal, or symbiotic relationships has not been documented.

Human Interactions:  The targeting of  Impatient Sea Cucumbers by fisheries has not been doucumented, however they are probably the target of artisanal fisheries, as are other sea cucumber species. Otherwise, Impatient Sea Cucumbers have no direct impact on human activities. From a conservation perspective the the Impatient Sea Cucumber has not been formally evaluated however they are fairly common with a very wide distribution and should be consider to be of Least Concern.

Synonyms: Fistularia impatiens, Holothuria (Thymiosycia) impatiens bicolor, Holothuria (Thymiosycia) impatiens concolor, Holothuria (Thymiosycia) impatiens lutea, Holothuria (Thymiosycia) impatiens pulchra, Holothuria (Thymiosycia) impatiens var. bicolor, Holothuria (Thymiosycia) impatiens var. concolor, Holothuria (Thymiosycia) impatiens var. lutea, Holothuria (Thymiosycia) impatiens var. pulchra, Holothuria botellus, Holothuria fulva, Holothuria impatiens, Holothuria impatiens var. bicolor, Holothuria impatiens var. concolor, Holothuria impatiens var. lutea, Holothuria impatiens var. pulchra, and Holothuria ophidiana.