Geographic Range
Galápagos damsels (
Azurina eupalama
) are marine fish found primarily in the eastern-central Pacific Ocean, specifically
near the Cocos and Galapagos Islands. They are non-migratory and are is classified
as a tropical fish species.
- Biogeographic Regions
- pacific ocean
Habitat
Galápagos damsels live in rocky reefs and open waters from 5 to 30 m. However, Galápagos
damsels have not been seen since 1983, during the El Niño event of 1982 to 1983. During
this event, warm waters spread throughout the central and eastern-central Pacific
Ocean. Scientists believe that they are likely extinct in the waters surrounding the
Cocos and Galápagos islands, and it is unsure whether or not they moved elsewhere
in order to survive.
- Habitat Regions
- saltwater or marine
- freshwater
Physical Description
The most identifiable features of Galápagos damsels are their long, slender bodies,
pointed heads, and their gray-, white-, and blue-colored bodies. The word "Azurina"
in the scientific name
Azurina eupalama
is Latin for pale blue, which is one of main colors found on Galápagos damsels. They
can reach sizes of up to 15 cm and have 13 dorsal spines, 10 to 11 dorsal soft rays,
2 anal spines, and 11 to 12 anal soft rays.
- Other Physical Features
- ectothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
Development
Galápagos damsels have pelagic larvae and produce benthic offspring. Their pelagic
larvae disperse over large distances and may be moved away from their original habitats.
Benthic fish, like adult Galápagos damsels, live on or near the bottom of the sea;
depths can vary based on the different habitats. Researchers determine the sex of
Galápagos damsels by analyzing the appearance of offspring. Males tend to have slimmer
yet larger bodies than females as well as more pointed fins. Unfortunately, other
information like the involvement of metamorphosis and indeterminate growth in Galápagos
damsels is unknown at this time.
- Development - Life Cycle
- neotenic/paedomorphic
Reproduction
There is currently little information on the mating systems of Galápagos damsels.
However, it is known that there is distinct pairing during breeding and that they
are oviparous fish.
- Mating System
- monogamous
Galápagos damsels are oviparous fish, meaning they lays eggs. Their eggs are demersal,
which means they stay at the bottom of the sea and essentially adhere to the bottom
layer of the sea. Galápagos damsel males protect and aerate eggs. Not much else is
known about the reproduction habits in Galápagos damsels at this time. This information
includes breeding and spawning seasons, time to hatch, and birth information.
- Key Reproductive Features
- oviparous
Not much is known about parental investment in Galápagos damsels. However, what is
known is that males protect and aerate eggs before they hatch.
- Parental Investment
-
pre-hatching/birth
-
protecting
- male
-
protecting
Lifespan/Longevity
There is currently no information about the lifespan of Galápagos damsels in captivity
or in the wild. However, they have not been sighted since 1983 during the El Niño
event of 1982 to 1983>>.
Behavior
Galápagos damsels are a motile, natatorial fish that prefer open waters near reefs
and drop-offs up to a depth of 30 m.
- Key Behaviors
- natatorial
- motile
- sedentary
Home Range
Galápagos damsels are non-migratory fish, distributed in the Eastern Central Pacific
Ocean - more specifically the Cocos and Galapagos Islands. Currently, there is no
information on the activity patterns, sociability, or other aspects on the behavior
of Galápagos damsels.
Communication and Perception
Galápagos damsels perceive their environment through the use of touch, taste, and
smell. At this time, no other forms of communication and perception are known for
Galápagos damsels.
Food Habits
Galápagos damsels feed mostly on plankton and are considered to be planktivores. More
specifically, they have been known to feed on zooplankton, pelagic fish larvae, pelagic
crustacea, and pelagic fish eggs.
- Primary Diet
-
carnivore
- eats eggs
- eats non-insect arthropods
- eats other marine invertebrates
- planktivore
- Animal Foods
- eggs
- aquatic crustaceans
- zooplankton
Predation
Currently, there is no information on the predation of Galápagos damsels.
Ecosystem Roles
At this time, there is little to no information about the ecosystem roles of Galápagos
damsels. However, it is likely that they are not a keystone species in their habitat,
since there has been no correlation between their population decline and the condition
of their former habitats.
- There are no known species that Galápagos damsels use as hosts at this time.
- There are no known species that Galápagos damsels are mutualistic with at this time.
- There are no known species that use Galápagos damsels as hosts at this time.
Economic Importance for Humans: Positive
Currently, there is no information on Galápagos damsels that suggests they have any significant economic impact, negative or positive.
Economic Importance for Humans: Negative
Currently, there is no information on Galápagos damsels that suggests they have any significant economic impact, negative or positive.
Conservation Status
It is known that Galápagos damsels have been listed as a critically endangered species since the El Niño event of 1982 and 1983. During this time, an increase in sea temperatures negatively impacted the marine fauna and flora of the Galápagos islands, ultimately decreasing the food supply ofGalápagos damsels. The IUCN Red List lists them as a critically endangered species. Currently, the U.S. Federal List, CITES, and the State of Michigan List have no status for Galápagos damsels.
Although researchers have continued to search for Galápagos damsels, no conservation
efforts are known at this time. However, researchers may potentially look into whether
or not they have expanded past their usual habitat in order to survive.
Other Comments
There are no other comments about Azurina eupalama at this time.
Additional Links
Contributors
Erynn Cominsky (author), Colorado State University, Brooke Berger (editor), Colorado State University, Galen Burrell (editor), Special Projects.
- Pacific Ocean
-
body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- saltwater or marine
-
mainly lives in oceans, seas, or other bodies of salt water.
- freshwater
-
mainly lives in water that is not salty.
- benthic
-
Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.
- reef
-
structure produced by the calcium carbonate skeletons of coral polyps (Class Anthozoa). Coral reefs are found in warm, shallow oceans with low nutrient availability. They form the basis for rich communities of other invertebrates, plants, fish, and protists. The polyps live only on the reef surface. Because they depend on symbiotic photosynthetic algae, zooxanthellae, they cannot live where light does not penetrate.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- monogamous
-
Having one mate at a time.
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- natatorial
-
specialized for swimming
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
- zooplankton
-
animal constituent of plankton; mainly small crustaceans and fish larvae. (Compare to phytoplankton.)
- carnivore
-
an animal that mainly eats meat
- planktivore
-
an animal that mainly eats plankton
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
References
Aguilar-Medrano, R. 2018. "Ecomorphological Trajectories of Reef Fish Sister Species (Pomacentridae) from Both Sides of the Isthmus of Panama". Zoomorphology , 137: 315-327. Accessed March 03, 2020 at doi:10.1007/s00435-017-0391-6 .
Allen, G., R. Robertson, R. Rivera, G. Edgar, G. Merlen, F. Zapata, E. Barraza. 2010. "Galapagos Damsel" (On-line). IUCN Red List. Accessed March 03, 2020 at https://www.iucnredlist.org/species/184017/8219600#conservation-actions .
Bernardi, G., L. Marina, Y. Alva-Campbell, J. McCosker, G. Bucciarelli, L. Garske, B. Victor, N. Crane. 2014. Darwin's Fishes: Phylogeography of Galápagos Islands Reef Fishes. Bulletin of Marine Science , 90: 533-549. Accessed February 08, 2020 at https://www.ingentaconnect.com/content/umrsmas/bullmar/2014/00000090/00000001/art00022# .
Carlowicz, M., S. Schollaert. 2017. "El Niño" (On-line). NASA Earth Observatory. Accessed March 09, 2020 at https://earthobservatory.nasa.gov/features/ElNino .
Froese, R., D. Pauly. 2020. " Azurina eupalama Heller & Snodgrass, 1903" (On-line). World Resource of Marine Species. Accessed March 09, 2020 at http://www.marinespecies.org/aphia.php?p=taxdetails&id=279851 .
Grove, J., R. Lavenberg. 1997. The Fishes of the Galápagos Islands . Stanford: Stanford University Press.
Monte-Luna, P., D. Lluch-Belda, E. Serviere-Zaragoza, R. Carmona, H. Reyes-Bonilla, D. Aurioles-Gamboa, J. Castri-Aguirre, S. Guzman del Proo, O. Trujillo-Millan, B. Brook. 2007. Marine Extinctions Revisted. Fish and Fisheries , 8/2: 107-122. Accessed February 08, 2020 at https://doi.org/10.1111/j.1467-2679.2007.00240.x .
Reyes, R., S. Luna. 2008. "Azurina Eupalama Summary Page" (On-line). FishBase. Accessed March 03, 2020 at www.fishbase.se/summary/Azurina-eupalama.html .
Simons, E. 2014. "The Fish We Never Knew" (On-line). Bay Nature. Accessed March 03, 2020 at https://baynature.org/article/fish-never-knew/ .
2017. "Galapagos Damsel" (On-line). Extinction. Accessed March 09, 2020 at https://www.extinction.photo/species/galapagos-damsel/ .