Archosargus pourtalesii
Rare Galápagos sea bream logged in warm 23.5-24.6C water, spotted year-round across the islands' reefs and rocky slopes.
Look for a deep-bodied, silvery fish around 25 cm with the sharp profile typical of sea breams, plus a dark blotch near the upper shoulder that gives the species its name. The body is compressed and oval, with faint vertical banding that can fade in and out depending on light and mood. There is no noted difference between juveniles and adults in the data, so the shoulder spot is the main feature to key on at any life stage.
Divers most often log this species as a solitary or loosely grouped fish moving over rocky bottom rather than open water, consistent with a bream that picks around structure for food. It is logged as rare to uncommon at most Galápagos sites, with only one site reporting it as common, so patient, slow-swimming divers scanning rock crevices and boulder fields have the best odds. It does not appear to show strong reactions to divers in the data, behaving like a fish that tolerates a respectful distance rather than fleeing.
It is one of the more range-restricted sea breams a diver can encounter, with every logged sighting coming from the Galápagos Islands rather than a wider tropical or Mediterranean spread typical of the sparidae family.
Sighting data does not show a clear season, and the observed water temperature range of 23.5 to 24.6C sits within the Galápagos' cooler, upwelling-influenced norm, so divers report it across the year rather than in one narrow window.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
This one is a Galápagos speciality, logged only from sites in Ecuador and concentrated entirely in the Galápagos Islands. If you are diving the archipelago's rocky reefs and volcanic slopes, this is the region where sightings actually happen.
Mapping where Blackspot Porgy is logged…
Sightings are concentrated in the Galápagos Islands, Ecuador, where divers log it over rocky reef and boulder terrain. It has not been reported from other regions in current diver data.
There is no detected seasonal pattern, and it is recorded year-round in water around 23.5 to 24.6C, so timing your Galápagos trip for this species alone is not necessary.
Look for a silvery, deep-bodied fish about 25 cm long with a dark blotch on the upper shoulder area. Faint vertical bars may show on the flanks, and the overall shape follows the classic sea bream outline.
Around 25 cm is typical for adults, a modest mid-sized sea bream rather than a large reef fish.
No, this species poses no known danger to divers and is not aggressive or venomous.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Boga
2,853 sites
