Rarest animals seen in a zoo or aquarium

This list is a bit biased towards vertebrates - some of the invertebrate rarities we have at Bristol:

Christmas Island Blue land crab
Partula snails (various species)
Fregate beetle
Fregate millipede

 

Do you have a scientific name for it? Google search for 'Christmas Island Blue land crab' gives only a single result, your post. Perhaps you meant the famous Christmas Island red crab, Gecarcoidea natalis? Or perhaps 'blue land crab', Cardisoma guanhumi? A big species from the Americas, not Christmas Island.

 

I saw them in March - absolutely stunning creatures. They're labelled as Discoplax hirtipes.

I've attached a photo of the animals - not the greatest so will have to try again next time! - and the sign.

 

Sorry, I should have quoted the scientific name. I gather there are actually several land crab species on Christmas island - the Discoplax have done better on display than the Christmas island Red crabs. As there are so many different land crab species worldwide, and they are so important in tropical island ecosystems, I am a bit surprised there are not more exhibits - I would have thought some of the Carribean species at least should be readily obtainable for US zoos.

 

I will mention mexican and brazilian zoos, because the european and north american zoos are very well covered on this thread. Some of these species are unusual in collections in other countries. These are species i have seen in the last decade.
Mexico
Volcano rabbit: Chapultepec Zoo, Los Coyotes Zoo
Horned Guan: Africam Safari park, Zooleon, Zoomat Chiapas
Mexican Brocket Deer: Africam Safari Park, Zooleon, Zoomat Chiapas, Aragon Zoo, Chapultepec Zoo
Respladescent Quetzal: Zoomat Chiapas
Mexican Beaded Lizard black subspecies: ( heloderma horridum alvarezi) Zoomat Chiapas, Chapultepec Zoo
Peninsular Pronghorn Antelope: Aragon Zoo
Mexican Black Howler Monkey: Zoomat chiapas, Aragon Zoo, Chapultepec Zoo, Xcaret park
Greater Grison: Zoomat Chiapas, Aragon Zoo, Xcaret park
Tayra: Zoomat Chiapas, Xcaret park
Margay: Zoomat Chiapas, Aragon Zoo, Xcaret park
Jaguarundi: Zoomat Chiapas, Chapultepec Zoo, Xcaret Park
endangered mexican amphibians: Africam Safari Park, Zoomat Chiapas
Mexican tamandua: Aragon zoo, Zoomat chiapas

Brazil
Lear´s macaw: Riozoo
red Howler Monkey: Riozoo, sao Paulo Zoo a free ranging colony
Black lion tamarin: Riozoo. Sao Paulo Zoo
orange chested dusty titi: Riozoo
bearded saki: Riozoo
yellow breasted capuchin monkey: Riozoo, Sao paulo zoo
crab eating fox: Riozoo
amazon raccoon: Riozoo
Jaguarundi: Riozoo, Sao Paulo Zoo
Margay: Riozoo, Sao paulo Zoo
jaibiru stork: Sao paulo zoo

 

Thanks Maguari and Zoovolunteer. Hadn't seen the name Christmas Island blue crab (without 'land') before either but google search suggests it is a fairly common name for the species though not restricted to that island. Stunning light blue creatures. More zoos should keep land crabs. Don't require much space and there are several great looking species like Grapsus grapsus and Gecarcinus quadratus.

 

At least seven but only the red is near-endemic: In addition to red and blue there are Epigrapsus politus, Geograpsus grayi, G. crinipes, Sesarma obtusifrons and S. jacksoni but their appearance is not nearly as remarkable as the first two. Also four land hermit crabs: Coconut crab, Coenobita rugosus, C. brevimanus and C. perlatus.

While we're at the group:
Coconut crab at Parc Paradisio.

 

I've finally wrangled up a list for the rarest bird species that I've seen:

African Golden Oriole (Oriolus auratus) – Columbus Zoo
•Bay-headed Tanager (Tangara gyrola) – Louisville Zoo
•Black Curassow (Crax alector) – Cincinnati Zoo
•Black-collared Fruit-Pigeon (Ducula mullerii mullerii) – Cincinnati Zoo
•Black-faced Ibis (Theristicus melanopis) – Cincinnati Zoo
•Black-winged Lory (Eos cyanogenia) – Louisville Zoo
•Black-winged Red Bishop (Euplectes hordeaceus) – Cincinnati Zoo
•Blue Dacnis (Dacnis cayana) – Louisville Zoo, Memphis Zoo
•Blue-backed Fairy Bluebird (Irena puella puella) – Louisville Zoo, Memphis Zoo
•Blue-breasted Kingfisher (Halcyon malimbica) – Cincinnati Zoo
•Blue-masked Leafbird (Chloropsis venusta) – Memphis Zoo
•Blue-naped Mousebird (Urocolius macrourus) – Cincinnati Zoo, Memphis Zoo
•Blue-streaked Lory (Eos reticulata) – Cincinnati Zoo
•Broad-ringed White-eye (Zosterops poliogaster) – Memphis Zoo
•Broad-tailed Paradise Whydah (Vidua orientalis) – Memphis Zoo
•Central Red-tailed Black Cockatoo (Calyptorhynchus banksii samueli) – Cincinnati Zoo
•Central Stella’s Lory (Charmosyna papou goliathina) – Louisville Zoo
•Common Murre (Uria aalge) – Cincinnati Zoo
•Congo Peafowl (Afropavo congensis) – Cincinnati Zoo
•Crested Auklet (Aethia cristatella) – Cincinnati Zoo
•Double-crested Cormorant (Phalacrocorax auritus) – Cincinnati Zoo
•East African Openbill Stork (Anastomus lamelligerus lamelligerus) – Louisville Zoo
•Eastern Rosella (Platycercus eximius eximius) – Columbus Zoo
•Eastern Yellow-billed Hornbill (Tockus flavirostris) – Cincinnati Zoo
•Goldie’s Lorikeet (Psitteuteles goldiei) – Columbus Zoo, Louisville Zoo
•Guam Rail (Gallirallus owstoni) – Cincinnati Zoo
•Harlequin Duck (Histrionicus histrionicus) – Cincinnati Zoo
•Hawaiian Hawk (Buteo solitarius) – Louisville Zoo
•Horned Puffin (Fratercula corniculata) – Cincinnati Zoo
•Hooded Pitta (Pitta sordida mulleri) – Memphis Zoo
•Hottentot Teal (Anas hottentota) – Columbus Zoo
•Imperial Shag (Phalacrocorax atriceps) – Cincinnati Zoo
•Javan Pond Heron (Ardeola speciosa) – Columbus Zoo
•Least Auklet (Aethia pusilla) – Cincinnati Zoo
•Lesser Adjutant (Leptoptilos javanicus) – Cincinnati Zoo
•Little Blue Penguin (Eudyptula minor novaehollandiae) – Cincinnati Zoo
•Louisiana Tri-colored Heron (Egretta tricolor ruficollis) – Cincinnati Zoo
•Malayan Crestless Fireback (Lophura erythrophthalma erythrophthalma) – Columbus Zoo
•Masked Bobwhite (Colinus virginianus ridgwayi) – Cincinnati Zoo
•North Island Brown Kiwi (Apteryx mantelli) – Columbus Zoo
•Northern Carmine Bee-eater (Merops nubicus) – Cincinnati Zoo
•Olive-headed Lorikeet (Trichoglossus euteles) – Cincinnati Zoo, Louisville Zoo
•Oriental White Stork (Ciconia boyciana) – Louisville Zoo
•Oriental White-eye (Zosterops palpebrosa) – Louisville Zoo
•Ornate Lorikeet (Trichoglossus ornatus) – Cincinnati Zoo, Cleveland Zoo
•Pale-headed Lorikeet (Trichoglossus haematodus caeruleiceps) – Cleveland Zoo
•Peruvian Pigeon (Columba oenops) – Cincinnati Zoo
•Pesquet’s Parrot (Psittrichas fulgidus) – Cincinnati Zoo
•Pigeon Guillemot (Cepphus columba columba) – Cincinnati Zoo
•Raggiana Bird-of-Paradise (Paradisaea raggiana) – Cincinnati Zoo
•Red-breasted Merganser (Mergus serrator) – Cincinnati Zoo
•Red-billed Blue Magpie (Urocissa erythrorhyncha erythrorhyncha) – Memphis Zoo
•Red-collared Lorikeet (Trichoglossus rubritorquis) – Cincinnati Zoo
•Red-crested Bustard (Lophotis gindiana) – Cincinnati Zoo, Columbus Zoo
•Red-flanked Lorikeet (Charmosyna placentis placentis) – Cincinnati Zoo, Louisville Zoo
•Red-rumped Cacique (Cacicus haemorrhous) – Cincinnati Zoo
•Rhinoceros Hornbill (Buceros rhinoceros borneoensis) – Cincinnati Zoo
•Saipan White-eye (Zosterops conspicillatus saypani) – Louisville Zoo, Memphis Zoo
•Scaly-breasted Lorikeet (Trichoglossus forsteni forsteni) – Cincinnati Zoo
•Scarlet-chested Parrot (Neophema splendida) – Cincinnati Zoo
•Scarlet-headed Blackbird (Amblyramphus holosericeus) – Memphis Zoo
•Shoebill (Balaeniceps rex) – Cincinnati Zoo
•Siberian White Crane (Grus leucogeranus) – Cincinnati Zoo
•Spangled Cotinga (Cotinga cayana) – Cincinnati Zoo, Memphis Zoo
•Speckled Pigeon (Columba guinea phaeonota) – Columbus Zoo
•Spectacled Eider (Somateria fischeri) – Cincinnati Zoo
•Superb Parrot (Polytelis swainsonii) – Cincinnati Zoo
•Temminck’s Fruit Dove (Ptilinopus porphyrea) – Louisville Zoo, Memphis Zoo
•Thick-billed Parrot (Rhynchopsitta pachyrhyncha pachyrhyncha) – Cincinnati Zoo
•Tinian Island Monarch Flycatcher (Monarcha takatsukasae) – Memphis Zoo
•Violacious Euphonia (Euphonia violacea) – Louisville Zoo, Memphis Zoo
•Wattled Jacana (Jacana jacana) – Cleveland Zoo, Louisville Zoo
•Weber’s Lorikeet (Trichoglossus weberi) – Cincinnati Zoo
•Whiskered Auklet (Aethia pygmaea) – Cincinnati Zoo
•White-crowned Robin Chat (Cossypha albicapilla albicapilla) – Columbus Zoo
•White-naped Raven (Corvus albicollis) – Cincinnati Zoo
•White-tailed Trogon (Trogon viridis) – Louisville Zoo, Memphis Zoo
•Wompoo Fruit Dove (Ptilinopus magnificus) – Louisville Zoo, Memphis Zoo
•Yellow-hooded Blackbird (Agelaius icterocephalus) – Louisville Zoo, Memphis Zoo
•Yellow Rail (Coturnicops noveboracensis) – Columbus Zoo

 

I'd like to add to the comment by Carlos. Breeding groups/pairs of Hyacinth Macaws , resplendant Quetzals and Harpy eagles can all be found at "El nido" aviary in Mexico. I dont think they are very common species found in European zoo's.

 

It seems Hyacinthe Macaws are fairly uncommon; I only remember seeing them at Toronto, and they no longer have the species.

 

Blackduiker

Hawaiian Monk Seal (Waikiki Aquarium)
Saiga (Los Angeles)
Mountain Tapir (Los Angeles)
Tahiti Blue Lorii (San Diego)
Monkey-eating Eagle ( Los Angeles)
Tasmanian Devil (Los Angeles, San Diego)
Golden Snub-nosed Monkey (Los Angeles, San Diego)
Giant Panda (Los Angeles, San Diego)
Peninsular Pronghorn (Los Angeles)
California Condor (Los Angeles, Santa Barbara)
Congo Peafowl (Los Angeles)
Zebra Duiker (Los Angeles)
Bush Dog (Los Angeles, Saint Louis)
Visayan Warty Pig (Los Angeles, Saint Louis)
Red Uakari (Los Angeles)
Crested Capuchin (Los Angeles)
Chacoan Peccary (San Diego, Los Angeles, Phoenix)
Musk Ox (San Francisco)
Blue-eyed Lemur (Los Angeles)
Pacarana (Los Angeles, San Diego)
Marbled Cat (Los Angeles)
Gray's Monitor (Los Angeles)
Aye-aye (San Francisco)
Pilot Whale (Marineland of the Pacific) closed
Desert Monitor (Los Angeles)
Ploughshare Tortoise (Los Angeles)
Giant Otter (Los Angeles)

 

Royal Antelope (Los Angeles, San Diego)
Chacoan Peccary (Los Angeles, San Diego)
Peninsular Pronghorn (Los Angeles)
Central Chinese Goral (Los Angeles, San Diego)
Japanese Serow (Los Angeles)
Harpy Eagle (Los Angeles)
Calamian Deer (Los Angeles, San Diego)
Chinese Water Deer (Los Angeles)
Mountain Tapir (Los Angeles)
Giant Otter (Los Angeles)
California Condor (Santa Barbara, San Diego)
Channel Island Fox (Los Angeles, Santa Barbara)
Kiwi (San Diego, Washington DC)
Siberian Lynx (San Diego)
Exuma Island Iguana (Los Angeles)
Gray's Monitor (Los Angeles)
Giant Eland (Los Angeles)
Nene (Honolulu)
Gharial (San Diego, Honolulu)
Blue-eyed Lemur (Los Angeles)
Pacarana (Los Angeles)
Crested Capuchin (Los Angeles)
Red Uakari (Los Angeles)
Sumatran Rhino (Los Angeles)
Tahiti Blue Lory (San Diego)
Gang-gang Cockatoo (San Diego)
Golden-bellied Mangabey (San Diego)
Wombat (San Diego)
African Crowned Eagle (Los Angeles, San Diego)
Solitary Eagle (Los Angeles)
African Fish Eagle (Los Angeles)
Japanese Mountain Hawk-eagle (Los Angeles)
Black Duiker (Los Angeles)
Desert Bighorn Sheep (Los Angeles)
Couch's Spadefoot Toad (Los Angeles)

Once the new LAIR exhibit opens at the LA Zoo then I'll add more since there will be some first for me that are consider quite rare in the zoo world.

EDIT: I added some new species...

 

Off the top of my head:
Superb Lyrebird (Adelaide)
Australian Pratincole (Adelaide)
Razor-billed Curassow (Adelaide)

I'm not sure if these count but Mesopotamian Fallow Deer (Monarto) and Black Lion Tamarin (Adelaide)

 

Chacoan Peccary
Brazilian Ocelot
Okapi
Babirusa
Visyan Warty Pig
New Guinea Singing Dog
Shoebill Stork
Striped HYena
Pygmy Hippo
Key Deer
Northern Fur Seal
Florida Panther
Clouded Leopard
Steller Sea Lion
American Crocodile
Cuban Crocodile
Calico Lobster
Guinea Hog
Pere David's Deer

 

Persian Leopard - cleveland zoo

any King Cheetah's in the USA?

 

Assuming they are both still alive (which I do not know for sure), there are two. The problem is, they are ambassador animals that are only brought out for presentations on select days and are not on full time view to the public.

One is at the Wild Cat Education and Conservation Fund (formerly known as Leopards etc). This is a private compound in Occidental, California (near the San Francisco bay area) that is closed to the public but does public presentations at various places. The other is at Miami Metrozoo, but is kept off exhibit and only used in their shows. This is a huge mistake IMO. If they are the only public zoo in North America with a king cheetah, why in the world don't they build an exhibit and promote it like crazy?

 

- Orinoco river dolphin (Duisburg)
- Commerson Dolphin (Duisburg)
- Beluga (Duisburg)
- Sotalia Dolphin (Munster)
- Harbour porpoise (Harderwijk)
- Stellers sea lion (Harderwijk)
- Baikal seal (Leipzig)
- Proboscis monkey (Apenheul)
- Douc langur (Cologne)
- Eastern Lowland gorilla (Antwerpen)
- Dune gazelle (Planckendael)
- Saiga (Cologne)
- Appenine Chamois (Munich)
- Kit fox (Vulpes macrotis) (Burgers Zoo)
- African wolf (egyptian jackal) (Burgers Zoo)
- Sea otter (Diergaarde Blijdorp)
- Black and rufous elephant shrew (Diergaarde Blijdorp)
- Rufous elephant shrew (Cologne)
- Australian wombat (Planckendael)
- Echidna (Planckendael, Diergaarde Blijdorp, Duisburg)

 

Okapi can also be found at the Columbus Zoo. Note sure about how rare they are but what about the manned wolf found at the Louisville zoo? I haven't seen them at any other zoo I've visited in America.

 

Okapi: Bronx, San Diego (zoo and animal park), Los Angeles, Brookfield, Denver, Jacksonville, Miami, Disney AK, Dallas, Cincinnatti, Omaha, Houston, Philadelphia....

Maned Wolves: Los Angeles, Audubon, Boise, Houston, Phoenix, Denver, Oklahoma City....

Both species are much more "common" than in past decades