AnimaliaHighest rank in taxonomy. Groups all life into domains: Animalia, Plantae, Fungi, etc.IUCN LCInternational Union for Conservation of Nature — the world authority on species extinction risk, using standardized criteria. — Least Concern — widespread and abundant; not at immediate risk of extinction.DraftCurrent stage of this record in the editorial review workflow. Recent Sighting
Abudefduf saxatilis
Sergeant Major
(Linnaeus, 1758)
Detailed Texts Multi-lang
A small to medium fish with a yellow back, silvery-white sides, and five distinct vertical black stripes on its body.
Added by
Anonymous Curator
Reviewed by
Under Review
Last modified by
Julia Trouin
TaxonomyBiological classification ranks placing this species within the tree of life, from Kingdom down to Genus.
PhylumRank below Kingdom. Groups organisms sharing a fundamental body plan (e.g., Chordata = vertebrates and some invertebrates).Chordata
ClassRank below Phylum. Subdivides by structural traits (e.g., Mammalia, Aves, Reptilia, Insecta).Actinopterygii
OrderRank below Class. Groups related families sharing common ancestry (e.g., Carnivora, Primates).Perciformes
FamilyRank below Order. Groups closely related genera (e.g., Felidae = cats, Canidae = dogs).Pomacentridae
GenusRank just above Species. The first word in the two-part binomial scientific name.Abudefduf
Taxonomic AuthorityThe scientist who first formally described and published this species, followed by the year of publication.(Linnaeus, 1758)
Record Completeness
95%Coming soon
Ecology & StatusHow this species lives: habitat preferences, diet, behavior, population status, and role in its ecosystem.
OriginWhether the species is native (evolved here), endemic (found only here), or introduced by human activity.
Native
Population TrendDirection of change in population size over time: increasing, stable, decreasing, or unknown.
Stable
Breeding SeasonTime of year when this species typically reproduces or flowers.
Year Round
Trophic RolePosition in the food chain: producer, herbivore, carnivore, omnivore, decomposer, or parasite.
Omnivore
Recent SightingsWhether this species has been observed in the wild in Costa Rica within recent years.
Yes
Habitat SummaryOverview of the specific ecosystems and environments where this species is found in Costa Rica. Multi-lang
Widely distributed in tropical and subtropical reefs, rocky outcrops, and shallow coastal waters.BehaviourDaily activity patterns, movement, territory use, foraging style, and seasonal behavioral changes. Multi-lang
Diurnal, highly active fish that feed on a variety of small prey and organic matter.Social ActivitySocial structure: whether the species is solitary, paired, or colonial; hierarchy and communication. Multi-lang
Very social; commonly found in large schools.Feeding GuildWhat the species eats, how it forages or hunts, and its role as a consumer in the food web. Multi-lang
Generalist/Omnivore.Trophic Chain DetailsSpecific interactions in local food webs: prey species, predators, competitors, and scavengers. Multi-lang
Omnivore; diet includes algae, copepods, small fish, and floating debris.Reproductive BehaviourMating strategies, courtship displays, nesting or spawning behavior, and parental care. Multi-lang
Benthic egg-layer; males prepare nest sites and defend them aggressively.Physical Measures
Length (cm)
5.0 - 20.0 cm
Weight (Grams)
20 g - 200 g
Offspring per cycleTypical number of young (live births, eggs, or seeds) produced by one adult in a single reproductive event or breeding season.5000 - 20000
Sexual DimorphismObservable physical differences between males and females of the same species (e.g., size, coloration, features).No
Lifespan
Sexual MaturityAge at which the individual becomes capable of reproducing for the first time.
1 - 2 Years
Gestation / IncubationDuration from fertilization to birth (mammals) or to hatching (egg-laying species).
1
Lifespan EstimatedExpected duration of life from birth to natural death under wild conditions.
Males3 - 5 Years
Females3 - 5 Years
Evolutionary AdaptationsInherited traits and behaviors that improve the species' survival and reproduction in its specific environment. Multi-lang
Aggressive territorial behavior allows them to protect their eggs and food sources from much larger fish.
Main ThreatsDocumented pressures reducing the population: habitat loss, hunting, disease, climate change, and invasive species. Multi-lang
Relatively resilient, but sensitive to extreme water temperature fluctuations and heavy coastal pollution.
Interesting FactsSurprising or notable facts that highlight what makes this species unique or ecologically important. Multi-lang
During mating season, males turn deep blue while fiercely defending their nest sites from intruders.