Welcome to the Invasive Xeniid Soft Coral Learning Exchange
(originally the Unomia Learning Exchange)
Species of soft octocorals of the family Xeniidae, which naturally occur in tropical, Indo-Pacific coral reefs, are now invasive in the Caribbean, Brazil, and Hawaii. Their rapid growth rates and efficient asexual dispersal mechanisms, combined with a lack of natural predators or diseases in these exotic destinations, enables xeniids to displace the local native benthos, reduce local biodiversity and may even expand the range of environments and habitat types that xeniids occupy.
We hosted a collaborative learning exchange in February 2024 about the invasive, non-native xeniid, Unomia stolonifera. Populations presumed to represent this species in Puerto Rico and Cuba have since been identified as Xenia umbellata; at present Unomia invasions are only known in Venezuela and Hawaii. Another two invasive xeniids occur in Brazil (Latissimia ningalooensis, Sarcothelia sp.) and we now include them here, too.
Your observations are important to help increase our collective understanding of these species in their non-native habitat.
This page is being updated. Please check back for new information.
February 23, 2024
The Unomia Learning Exchange:
Video : Webinar recording –A learning session and briefing alert on the potentially invasive soft coral, Unomia stolonifera, in the Caribbean
Presentation Slide Deck : A learning session and briefing alert on the potentially invasive soft coral, Unomia stolonifera, in the Caribbean (PDF)
August 7, 2024
Caribbean Invasive Pulse Coral Workshop
A U.S. Caribbean Invasive Pulse Coral Workshop was held at the University of Puerto Rico at Mayaguez’s Magueyes Island Marine Station August 7th. and 8th. 2024. The presentation session covered various aspects of species invasion such as preparedness, detection, biology, ecology, permitting, removal, funding, and communications. A Zoom component was offered in addition to the in-person meeting which was recorded. In-person attendees participated in a site visit for species identification and observation of current removal intervention methods. The workshop was coordinated by the U.S. Virgin Islands Department of Planning and Natural Resources (USVI DPNR), Puerto Rico Department of Natural and Environmental Resources and Florida Sea Grant. Funding for this workshop came from USVI DPNR’s NOAA Coal Reef Conservation Program cooperative agreement and Florida Sea Grant.
Your Reports and Photos are important to us.
Please include close in-situ photos with your reports.
Invasive Xeniid Tracking Map
Photo Gallery
Xeniids invasive to the Caribbean
Unomia – shows tentacles on stalk
Xenia umbellata. Photo Credit D Toldeo
Native Caribbean soft corals
These tentacles of these encrusting soft corals superficially resemble the larger, stalked tentacles of the invasive xeniid soft corals, but they are native to the Caribbean.
Erythropodium caribaeorum. Photo Credit Ken Marks, AGRRA
Briarium asbestinum. Photo Credit Ken Marks, AGRRA
Resources
The first incidence of an alien soft coral of the family Xeniidae in the Caribbean, an invasion in eastern Venezuelan coral communities, Juan Pedro Ruiz-Allais, Catherine S McFadden, Yehuda Benayahu, June 2014
The invasive octocoral Unomia stolonifera (Alcyonacea, Xeniidae) is dominating the benthos in the Southeastern Caribbean Sea., Juan Pedro Ruiz-Allais, Yehuda Benayahu and Oscar Miguel Lasso-Alcalá, June 2021
Presencia en Cuba de la especie marina invasora Unomia stolonifera (Gohar, 1938) (Octocorallia, Alcyonacea). Acciones para su control y eliminación, José Espinosa Sáez, Reynaldo Estrada-Estrada, Juan Ruiz-Allais, September 2023
Video: Collaborative eradication control efforts of Xenia umbellata (formerly Unomia stolonifera) in Cuba (Boca de Calderas, Feb. 2024). Videographer: Roberto Irurzun