Yellow-spotted Sea Fan, Pacifigorgia flavimaculata
Yellow-spotted Sea Fan, Pacifigorgia flavimaculata. Underwater photographs taken in Bahía de Banderas, Puerta Vallarta, Jalisco, July 2026. Photographs and identifications courtesy of Greg Timms, youtube.com/@Coralmasterdives-PuertoVallarta/videos.
Yellow-spotted Sea Fan, Pacifigorgia flavimaculata. Photograph courtesy of Ron Woheau, Zihuatanejo, March 2024. Identification courtesy of Greg Timms, youtube.com/@CoralmasterdivesPuertoVallarta/videos.
Yellow-spotted Sea Fan, Pacifigorgia flavimaculata. Underwater photograph taken in Bahía de Banderas, Puerta Vallarta, Jalisco, July 2026. Photograph courtesy of Mary Schofield, Puerto Vallarta, Jalisco. Identification courtesy of Greg Timms, you-tube.com/@CoralmasterdivesPuertoVallarta/videos.
Phylogeny: The Yellow-spotted Sea Fan, Pacifigorgia flavimaculata (Breedy & Guzmán, 2003), is an octocoral in the Gorgoniidae Family of Soft Corals. It was described by taxonomists Odalisca Breedy and Hector M. Guzmán in their 2003 monographic series on Central American octocorals. The specific epithet flavimaculata derives from Latin roots meaning “yellow-spotted,” referencing the distinctive visual coloration markings across its coenenchyme and polyp mounds.
Morphology: Yellow-spotted Sea Fan colonies are erect, loosely branched sea fans that tend to grow vertically (taller than they are wide), typically reaching dimensions of 13 cm (5.1 inches) in height and 9.0 cm (3.5 inches) in width. They have an exceptionally open, sparse, and irregular grid network, averaging only ~3 meshes/cm², with massive 2 cm long rectantualr holes and a noticeably rough, warty branch texture. The mesh spaces are heavily elongated and predominantly rectangular, stretching up to large dimensions of 2. 4 cm (0.95 inches) by 0.7 cm (0.28 inches). Their free-ending branchlets and marginal twigs are notably long. Individual branches are sturdy, reaching up to 2.5 mm in diameter. The surface of the coenenchyme (soft tissue connecting individual polyps) has a highly distinct warty, rough texture. The calyces (polyp cups) are closely arranged and evenly distributed around the branches. The calyces are prominent, heavily elevated, mound-like, and punctuated by large, oval polyp openings. When extended, the tentacles are a translucent white. The internal coenenchymal sclerites are composed of a mixture of brownish-red, yellow, and bicolored capstans, alongside highly ornamented spindles. In proper lighting it displays a reddish mesh framework dotted with contrasting pale or yellow polyp mounds.
Habitat and Distribution: Yellow-spotted Sea Fans selectively anchor onto solid rock substrates, shallow reef walls, and wave-exposed volcanic structures. The historical holotype was collected from a shallow rocky ledge at Punta Salsipuedes, Costa Rica, at a depth of 3 m (10 feet). Long considered as a localized endemic, restricted to Costa Rica, recent scientific surveys successfully extended its geographic range south to the coast of Ecuador, while expanding its known bathymetric range to depths of 3 m (10 feet) to 20 m (66 feet). They are endemic to the Tropical Eastern Pacific (Panamic Province) and have a limited, poorly documented, range in Mexican waters of the Pacific Ocean. It is only recently that they have been documented in Zihuatanejo, Guerrero and in Banderas Bay, Nayarit /Jalisco as evidenced by the photographs provided above.
Diet: Yellow-spotted Sea Fans are an azooxanthellate (non-photosynthetic) suspension feeder. Because its mesh windows are massively open, water flows through the fan with minimal hydrodynamic resistance, forcing the polyps to rely on high water velocities to effectively snare passing microplankton and marine snow.
Predators: Specific records of targeted predation of Yellow-spotted Sea Fans are rare, but its thick, nutrient-dense coenenchyme tissue is subject to seasonal grazing by specialized Panamic corallivores, including ovulid gastropods and nudibranchs.
Reproduction: Yellow-spotted Sea Fan colonies are gonochoric (male or female for life) During sexual reproduction, mature gametes are shed directly into the central digestive cavity (coelenteron) and spawned out through the mouth for external fertilization. The zygotes then under go a free-swimming planktonic planula larval stage. When the Larvae have found a suitable habitat, they settle the the substrate and attach as a founding polyp. This polyp then grows a new colony through asexual budding. Localized budding of the coenenchyme is also used to repair tissue lesions and elongate branches. Yellow-spotted Sea Fan propagation is based on environmental and lunar cues.
Ecosystem Interactions: While fine-meshed sea fans serve as visual windbreaks that shelter microscopic organisms, the coarse, irregular network of Yellow-spotted Sea Fans behaves differently. Its thick, rigid branches and long free terminal branchlets act as high-stability perching structures, allowing larger opportunistic reef invertebrates (such as brittle stars, arrow crabs, and crinoids) to climb away from the sea floor to feed safely in stronger water currents.
Human Interactions: Yellow-spotted Sea Fans are not subject to direct commercial harvest or aquarium extraction. They stand as an important scientific indicator for geographic distribution boundaries in Eastern Pacific benthic ecosystems. It remains highly vulnerable to mechanical breakage from dragging commercial gillnets and recreational boat anchors. From a conservation perspective the Yellow-spotted Sea Fan has not been formally evaluated.
Synonyms: None