The Panama ghost catshark (Apristurus stenseni) is a tiny deepwater catshark of the family Pentanchidae, about 23 cm (9 in) long as an adult male, known only from the continental slope of the Gulf of Panama at 915–975 m. It has the long flattened snout, small eyes, soft body and long low anal fin typical of its genus, and is dark brown to black all over.
Its diet has never been examined; relatives of the same size eat small shrimps, squid and lanternfish. Like every Apristurus whose breeding is known, it presumably lays eggs in horny cases. No diver has ever seen one. The IUCN lists it as Least Concern because no fishery works its depth.
- Maximum lengthAbout 23 cm (9 in), from the few known specimens
- WeightNever measured; a few tens of grams
- LifespanUnknown
- Depth range915–975 m (3,000–3,200 ft)
- DietUnknown; probably small crustaceans, squid and fish
- IUCN statusLeast Concern (assessed 2019)
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Chondrichthyes
- Order
- Carcharhiniformes
- Family
- Pentanchidae
- Genus
- Apristurus
- Species
- Apristurus stenseni
- Family (common)
- Deepwater catsharks
On this page
- How to recognise a Panama ghost catshark
- How big is a Panama ghost catshark?
- Where the Panama ghost catshark lives
- What the Panama ghost catshark eats
- Behaviour and adaptations to the deep slope
- Reproduction and lifespan
- Is the Panama ghost catshark dangerous?
- Conservation status
- Similar species and close relatives
- Frequently asked questions
- References
How to recognise a Panama ghost catshark
There is no photograph of a living Panama ghost catshark, and the description that follows rests on the preserved type specimens Stewart Springer used to name the species in 1979. They show a typical member of Apristurus: a soft-bodied shark with a long, broad, flattened snout that is longer than the width of the mouth, small eyes set far back along the head, large nostrils with flaps, and a mouth that reaches back beyond the level of the eyes with long labial furrows at each corner. The gill slits are small, and there are no spines in front of the dorsal fins.
The fins are where the genus gives itself away. Both dorsal fins are small and pushed far back along the body, the first beginning behind the origin of the pelvic fins, and the anal fin is long and low, running most of the way from the pelvic fins to the tail, which in turn is long and paddle-shaped without a distinct lower lobe. The skin is thin and covered in fine, close-set denticles that give it a velvety feel rather than the rough sandpaper of a larger shark. Colour is uniform dark brown to blackish, without spots, bars or pale fin margins, which is the plain livery of a shark that lives where no light reaches.
Separating it from other eastern Pacific Apristurus is a job for a specialist with a specimen in hand and depends on proportions, tooth shape and the number of vertebrae and intestinal spiral valve turns. The species name commemorates Niels Stensen, the seventeenth-century Danish anatomist who first showed that fossil "tongue stones" were shark teeth.
How big is a Panama ghost catshark?
Small, and the numbers are few. The adult male specimens on which the species is based measure about 23 cm (9 in) in total length, and no larger individual has been reported since. That puts the Panama ghost catshark among the smallest sharks known, comparable with the lollipop catshark of the Gulf of California and not far above the dwarf lanternsharks on our list of the ten smallest sharks. Females, egg cases and hatchlings have never been described, so there is no figure for size at birth or for sexual dimorphism, though in most Apristurus the sexes are similar in size and the young hatch at 8–10 cm.
The older version of this page gave an adult length of 1.5 ft (about 46 cm). That figure appears to have been borrowed from a larger relative and should be disregarded; the only measured adults are half that size. Nobody has weighed one, and a shark of this length and build would register a few tens of grams. The size bar below sets 23 cm against a 1.8 m diver, which makes the point better than any number: this is a shark that would fit across a person's outstretched hand.
Where the Panama ghost catshark lives
Every confirmed specimen comes from the continental slope of the Gulf of Panama, on the Pacific side of the isthmus, at depths of 915 to 975 m (3,000–3,200 ft). That is the whole known range: a single stretch of deep mud off Panama. It may well extend along the slope to Colombia and Ecuador to the south or towards Costa Rica to the north, because deep-slope habitat is continuous along that coast, but no survey has caught one there, and until one does the honest map is a small dot.
The habitat itself is well understood even if the shark is not. Below 900 m in the Gulf of Panama the water is cold, around 4–6 °C, completely dark, and sits within one of the most intense oxygen-minimum zones in the world's oceans, where dissolved oxygen falls to a fraction of surface values. The bottom is soft mud fed by the rich surface productivity of the Panama upwelling, so there is more food falling from above than in most deep water at this latitude. A small, slow, low-metabolism catshark is exactly the kind of fish that thrives under those conditions, which is why several other Apristurus occupy similar slopes from Mexico to Chile.
The species is one of a handful of sharks endemic to the eastern tropical Pacific slope, and the list of places below is correspondingly short.
1 country list the panama ghost catshark in their species guide; the count is the number of incidents attributed to it there in the SharkSider database. Browse every guide on sharks around the world and sharks in the US.
What the Panama ghost catshark eats
No stomach of this species has been examined and published, so its diet is unknown in the strict sense. The mouth and teeth allow a confident guess. The jaws carry many rows of tiny teeth, each with a central cusp flanked by smaller cusplets, a design for gripping small soft prey rather than cutting. In the better-studied members of the genus, such as the brown catshark off California and the Iceland catshark in the North Atlantic, that dentition is used on shrimps and other small crustaceans, small squid, lanternfish and the occasional worm, and the Panama ghost catshark almost certainly eats the same sort of thing.
Hunting at 950 m is done without light. The long snout is packed with ampullae of Lorenzini that detect the faint electric fields of animals buried in or resting on the mud, the large nostrils sample the water for the scent of carrion and prey, and the lateral line picks up the movements of swimming crustaceans. The shark probably cruises slowly just above the bottom, nose down, and takes whatever it bumps into, in the manner of a bloodhound rather than a hawk. Its small, weak jaws and soft body rule out anything that fights back, and its low body density, a feature of deep-sea catsharks whose livers are rich in oil, lets it hover over the mud with little effort.
Behaviour and adaptations to the deep slope
Nothing about the behaviour of the Panama ghost catshark has been observed directly; the specimens came up dead in trawls, and there are no submersible or camera records. What can be said is what the body of a deep-slope catshark is built for, and here the genus is consistent. Muscle is thin and watery, the skeleton is lightly calcified, and the liver is large and oily, all of which reduce the energy needed to stay off the bottom in cold water where food arrives slowly. The heart and gills are small, consistent with a metabolic rate far below that of a shallow-water shark of the same size.
The oxygen-minimum zone of the Gulf of Panama adds a further constraint. Fish that live inside it either tolerate very low oxygen or make short excursions into it and retreat. A catshark with soft tissues, large gill surface relative to its needs and a habit of doing very little at any one time is well placed to tolerate it, which is the pattern seen in the lollipop catshark of the Gulf of California, another tiny eastern Pacific species that lives inside a low-oxygen layer.
Social behaviour, migration and daily rhythms are unknown. Related species show no schooling and no seasonal movement beyond a possible shift up or down the slope, and there is no reason to expect the Panama ghost catshark to be different. It is a shark that spends its life alone in the dark within a few metres of the mud.
Reproduction and lifespan
Reproduction has never been recorded for this species, but the genus is uniform enough that the outline is not in doubt. Every Apristurus whose breeding is known is oviparous: the female lays eggs one at a time from each oviduct, enclosed in a tough, flattened case with long tendrils at the corners that catch on sponges, corals or other hard objects on the seabed. The embryo develops inside the case on its yolk for many months, in cold water probably more than a year, and hatches as a fully formed miniature of the adult.
For the Panama ghost catshark there are no egg cases in any collection, no measured hatchlings and no pregnant females, so litter size, the season of egg-laying and the size at hatching remain blank. The adult males of 23 cm were mature, which shows that the species matures at a very small size, a point worth remembering when a 25 cm catshark from the eastern Pacific is described as "juvenile" in a survey report.
Lifespan is also unknown. No one has attempted to age this species, and even in well-sampled deep-sea catsharks the vertebrae are too poorly calcified for growth rings to be read with confidence. Deep, cold, food-poor habitats generally produce slow-growing, long-lived fish for their size, so a lifespan well beyond that of a shallow-water shark of 23 cm is plausible, but plausibility is not data (see how long sharks live for what has actually been measured).
Is the Panama ghost catshark dangerous?
No, in the most complete sense possible. The SharkSider database has no incident attributed to this species, and there could not be one: the shark lives at 900 m and more, no diver has ever been in the water with it, and the only humans who have handled one are the scientists who sorted it from a trawl catch. At 23 cm with teeth built for shrimps, it could not injure a person even if the two somehow met, and a specimen lifted from a trawl net is limp and harmless in the hand. The practical advice usually given about sharks does not apply to an animal you will never see.
The relevant local hazards belong to other sharks entirely. Panama's Pacific and Caribbean coasts are home to bull and tiger sharks, and the country's small bite record, summarised on our shark attacks in Panama page, involves those species, never a catshark.
The SharkSider database has no incident attributed to this species. The database draws on the International Shark Attack File, the Global Shark Attack File and verified local reports, and is updated weekly.
Conservation status
The IUCN Red List lists Apristurus stenseni as Least Concern. That may seem an odd verdict for a species known from a handful of specimens, but the logic is sound: the category reflects threat, not knowledge, and there is no threat that anyone can identify. No fishery in the Gulf of Panama works the slope at 900 m, deep-water trawling is negligible off Central America, and the shark has no commercial value. A lack of records from an unfished habitat is not evidence of decline.
The species is not listed on any CITES appendix or on the Convention on Migratory Species, and Panama, which has some of the strongest shark legislation in Latin America for its coastal species, does not name it in law. Nor does it need to for now. The realistic future risks are the ones that face every deep-slope animal in the eastern Pacific: the expansion of deep-water fishing as shallow stocks fail, seabed disturbance from cable-laying or mineral exploration, and the slow spread and intensification of the oxygen-minimum zone as the ocean warms, which could squeeze the narrow depth band the shark occupies.
What the species most needs is to be caught again by a research cruise with the time to describe its females, egg cases and diet. Until then it stays where most deep-sea sharks sit on the Red List, unthreatened and almost unknown. The broader picture of which sharks are in trouble and why is on our why sharks are endangered page.
Similar species and close relatives
Apristurus is the largest shark genus, with around forty described species, and the eastern Pacific has its share. The nearest neighbours of the Panama ghost catshark are the brown catshark, which ranges from Alaska to Baja California and, in scattered records, to Panama and Peru; the longnose catshark of the Gulf of California slope, distinguished by its exaggerated snout; and the tiny lollipop catshark, which is a separate genus but shares the same low-oxygen slopes and the same hand-sized proportions. Further afield in the same genus are the ghost catshark and white ghost catshark of the North Atlantic, whose common names the Panama species shares only by convention, and the Iceland catshark, longfin catshark and pale catshark.
Further north on the same side of the ocean, and in a different family, the filetail catshark of the California and Baja California slope is the other deep-water catshark of the region; it is larger, with a comb of enlarged denticles along the top of the tail that the Panama ghost catshark lacks.
- Brown Catsharkspecies profile
- Longnose Catsharkspecies profile
- Lollipop Catsharkspecies profile
- Ghost Catsharkspecies profile
- White Ghost Catsharkspecies profile
- Filetail Catsharkspecies profile
Frequently asked questions
What is the Panama ghost catshark?
A tiny deep-sea catshark, Apristurus stenseni, in the family Pentanchidae. It was described in 1979 from a few specimens trawled on the continental slope of the Gulf of Panama at 915 to 975 m. Adult males measure about 23 cm. It is dark, soft-bodied and has never been observed alive.
How big is the Panama ghost catshark?
About 23 cm (9 in) in total length, based on the adult male type specimens; no larger individual has been reported. That makes it one of the smallest sharks known. Females and hatchlings have never been described, and no specimen has been weighed. An older figure of 1.5 ft on this page was wrong.
Where does the Panama ghost catshark live?
Only in the Gulf of Panama, on the Pacific side of the country, where all known specimens were caught at 915 to 975 m on the continental slope. The water there is cold, dark and very low in oxygen. It may also occur along the slope off Colombia, Ecuador or Costa Rica, but no specimen has confirmed that.
What does the Panama ghost catshark eat?
Nobody knows for certain because no stomach contents have been published. Its small multi-cusped teeth and long sensory snout match relatives such as the brown catshark, which eat shrimps and other small crustaceans, small squid and lanternfish, so the same diet is very likely. It finds prey in total darkness by smell and electric sense.
Is the Panama ghost catshark dangerous to humans?
No. It lives at around 950 m, where no swimmer or diver ever goes, and at 23 cm with teeth designed for shrimps it could not harm a person in any case. The SharkSider database has no incident attributed to it, and the only people who have ever handled one are the scientists who described it.
How does the Panama ghost catshark reproduce?
Almost certainly by laying eggs, as every Apristurus with known breeding does: one egg at a time from each oviduct, in a tough case with tendrils that anchor it to the seabed, hatching after many months. For this species no egg case, embryo or pregnant female has been found, so litter size and hatchling size are unknown.
Why is it called a ghost catshark?
Ghost catshark is a common name shared by several Apristurus species, originally coined for pale, soft North Atlantic species that look ghostly when brought up from the deep. The Panama species inherited the name from the genus rather than from its own appearance, which is dark brown to black. Its scientific name honours the Danish anatomist Niels Stensen.
Is the Panama ghost catshark endangered?
No. The IUCN lists it as Least Concern because no fishery operates at the depth it lives and it has no commercial value, even though the species itself is barely known. It is not on CITES or the Convention on Migratory Species. Future deep-water fishing or the spread of low-oxygen water are the only foreseeable threats.
How many Panama ghost catsharks have ever been found?
Only a handful, all from the original collections in the Gulf of Panama that Stewart Springer used to describe the species in 1979. No new specimens have been reported since, which is why its females, eggs, diet, lifespan and full range are still unknown. It is one of the least-known sharks in the eastern Pacific.
References
A small team focused on researching sharks and making marine biology easy to understand. Every page is reviewed against current species records and the SharkSider attack database, and updated when new incidents or research appear.
Published October 10, 2022 · Last updated September 22, 2026 · No incident attributed to this species in the SharkSider attack database, which is updated weekly.
