Endemism in the Hawaiian Islands

Located about 2,300 miles (3,680 km) from the nearest continental shore, the Hawaiian Islands are the most isolated group of islands on the planet. The plant and animal life of the Hawaiian archipelago is the result of early, very infrequent colonizations of arriving species and the slow evolution of those species—in isolation from the rest of the world's flora and fauna—over a period of at least 5 million years. As a consequence, Hawai'i is home to a large number of endemic species. The radiation of species described by Charles Darwin in the Galapagos Islands which was critical to the formulation of his theory of evolution is far exceeded in the more isolated Hawaiian Islands.

The relatively short time that the existing main islands of the archipelago have been above the surface of the ocean (less than 10 million years) is only a fraction of time span over which biological colonization and evolution have occurred in the archipelago. High, volcanic islands have existed in the Pacific far longer, extending in a chain to the northwest; these once mountainous islands are now reduced to submerged banks and coral atolls. Midway Atoll, for example, formed as a volcanic island some 28 million years ago. Kure Atoll, a little further to the northwest, is near the Darwin point—defined as waters of a temperature that allows coral reef development to just keep up with isostatic sinking. And extending back in time before Kure, an even older chain of islands spreads northward nearly to the Aleutian Islands; these former islands, all north of the Darwin point, are now completely submerged as the Emperor Seamounts.

The islands are well known for the environmental diversity that occurs on high mountains within a trade winds field. On a single island, the climate can differ around the coast from dry tropical (< 20 in or 500 mm annual rainfall) to wet tropical; and up the slopes from tropical rainforest (> 200 in or 5,000 mm per year) through a temperate climate into alpine conditions of cold and dry climate. The rainy climate impacts soil development, which largely determines ground permeability, which affects the distribution of streams, wetlands, and wet places.

The distance and remoteness of the Hawaiian archipelago is a biological filter. Seeds or spores attached to a lost migrating bird's feather or an insect falling out of the high winds found a place to survive in the islands and whatever else was needed to reproduce. The narrowing of the gene pool meant that at the very beginning, the population of a colonizing species was a bit different from that of the remote contributing population. This list does not include species extinct in prehistoric times.

Island formation

Throughout time, the Hawaiian Islands formed linearly from northwest to the southeast. A study was conducted to determine the approximate ages of the Hawaiian Islands using K–Ar dating of the oldest found igneous rocks from each island. Kauai was determined to be about 5.1 million years old, Oahu about 3.7 million years old and the youngest island of Hawaii about 0.43 million years old. By determining the maximum age of the islands, inferences could be made about the maximum possible age of organisms inhabiting the island. The newly formed islands were able to accommodate growing populations, while the new environments were causing high rates of new adaptations.

Human arrival

Human contact, first by Polynesians and later by Europeans, has had a significant impact. Both the Polynesians and Europeans cleared native forests and introduced non-indigenous species for agriculture (or by accident), driving many endemic species to extinction. Fossil finds in caves, lava tubes, and sand dunes have revealed an avifauna that once had a native eagle, two raven-size crows, several bird-eating owls, and giant ducks known as moa-nalos. Around 861 species of plants have been introduced to the islands by humans since its discovery by Polynesian settlers, including crops such as taro and breadfruit.

Today, many of the remaining endemic species of plants and animals in the Hawaiian Islands are considered endangered, and some critically so. Plant species are particularly at risk: out of a total of 2,690 plant species, 946 are non-indigenous with 800 of the native species listed as endangered.

Terrestrial vertebrates

Mammals

Hawaiian hoary bat (a.k.a. ʻŌpeʻapeʻa) (Lasiurus semotus) - endangered
Hawaiian monk seal (a.k.a. ʻIlio-holo-i-ka-uaua) (Neomonachus schauinslandi) - endangered
Synemporion keana (a species of vesper bat) - extinct

Birds

Hawaiian duck (a.k.a. Koloa) (Anas wyvilliana) - endangered
Laysan duck (Anas laysanensis) - critically endangered
Nene (a.k.a. Hawaiian goose) (Branta sandvicensis) - near threatened
Hawaiian petrel (Pterodroma sandwichensis) - endangered
Newell's shearwater (a.k.a. Hawaiian shearwater or 'a'o) (Puffinus newelli) - critically endangered
Hawaiian hawk (a.k.a. 'Io) (Buteo solitarius) - near threatened
Laysan rail (Porzana palmeri) - extinct
Hawaiian rail (Porzana sandwichensis) - extinct
Hawaiian gallinule (Gallinula chloropus sanvicensis)
Hawaiian coot (Fulica alai) - vulnerable
Hawaiian stilt (Himantopus himantopus knudseni)
Hawaiian black noddy (Anous minutus melanogenys)
Pueo (Asio flammeus sandwichensis) - endangered
Kauaʻi oʻo (Moho braccatus) - extinct
Oʻahu ʻōʻō (Moho apicalis) - extinct
Molokaʻi ʻōʻō (Moho bishopi) - extinct
Hawaiʻi ʻōʻō (Moho nobilis) - extinct
Kioea (Chaetoptila angustipluma) - extinct
Kāmaʻo (Myadestes myadestinus) - extinct
Puaiohi (Myadestes palmeri) - critically endangered
Olomaʻo (Myadestes lanaiensis) - critically endangered/extinct
- ʻAmaui (Myadestes lanaiensis woahensis) - extinct
ʻŌmaʻo (Myadestes obscurus) - vulnerable
Millerbird (Acrocephalus familiaris) - critically endangered
Hawaiʻi ʻelepaio (Chasiempis sandwichensis) - vulnerable
Oʻahu ʻelepaio (Chasiempis ibidis) - endangered
Kaua'i ʻelepaio (Chasiempis sclateri) - vulnerable
Hawaiian crow (Corvus hawaiiensis) - extinct in the wild
Laysan finch (Telespiza cantans) - vulnerable
Nihoa finch (Telespiza ultima) - critically endangered
Lesser koa finch (Rhodacanthus flaviceps) - extinct
Greater koa finch (Rhodacanthus palmeri) - extinct
Maui parrotbill (Pseudonestor xanthophrys) - critically endangered
ʻŌʻū (Psittirostra psittacea) - critically endangered/extinct
Palila (Loxioides bailleui) - critically endangered
Lanaʻi hookbill (Dysmorodrepanis munroi) - extinct
Kona grosbeak (Chlroidops kona) - extinct
Common ʻamakihi (Hemignathus virens) - least concern
Oʻahu ʻamakihi (Hemignathus flavus) - vulnerable
Kauaʻi ʻamakihi (Hemignathus kauaiensis) - vulnerable
Greater ʻamakihi (Hemignathus sagittirostris) - extinct
Maui nukupuʻu (Hemignathus affinis) - critically endangered/extinct
Kauaʻi nukupuʻu (Hemignathus hanapepe) - critically endangered/extinct
Oʻahu nukupuʻu (Hemignathus lucidus) - extinct
ʻAkiapolaʻau (Hemignathus munroi) - endangered
ʻAnianiau (Magumma parva) - vulnerable
Hawaiʻi ʻakialoa (Akialoa obscura) - extinct
Kauaʻi ʻakialoa (Akialoa stejnegeri) - extinct
Maui Nui ʻakialoa (Akialoa lanaiensis)- extinct
Oahu ʻakialoa (Akialoa ellisiana) - extinct
ʻAkekeʻe (Loxops caeruleirostris) - critically endangered
Hawaiʻi ʻakepa (Loxops coccineus) - endangered
Maui ʻakepa (Loxops ochraceus) - extinct
Oʻahu ʻakepa (Loxops wolstenholmei) - extinct
ʻAkikiki (Oreomystis bairdi) - critically endangered
Hawaiʻi creeper (Oreomystis mana) - endangered
Molokai creeper (Paroreomyza flammea) - extinct
Oʻahu ʻalauahio (Paroreomyza maculata) - critically endangered/extinct
Maui ʻalauahio (Paroreomyza montana) - endangered
Lanaʻi ʻalauahio (Paroreomyza montana montana) - extinct
ʻAkohekohe (a.k.a. Crested honeycreeper) (Palmeria dolei) - critically endangered
Poʻouli (Melamprosops phaeosoma) - critically endangered/extinct
ʻUla-ʻai-hawane (Ciridops anna) - extinct
ʻIʻiwi (a.k.a. Scarlet honeycreeper) (Drepanis coccinea) - vulnerable
Hawaiʻi mamo (Drepanis pacifica) - extinct
Black mamo (Drepanis funerea) - extinct
Laysan honeycreeper (Himantione fraithii) - extinct
ʻApapane (Himantione sanguinea) - least concern

Freshwater fishes

None of Hawaii's native fish are entirely restricted to freshwater (all are either anadromous, or also found in brackish and marine water in their adult stage).

ʻOʻopu nākea (Awaous stamineus)
Āholehole (Kuhlia xenura)
ʻOʻopu ʻalamoʻo (Lentipes concolor) - data deficient
ʻOʻopu naniha (Stenogobius hawaiiensis)
‘O‘opu ‘akupa (Eleotris sandwicensis) - data deficient
ʻOʻopu nōpili (Sicyopterus stimpsoni) - near threatened

Terrestrial invertebrates

Insects

Hyposmocoma (a genus of moths, such as the snail-eating caterpillar)
Agrotis (a genus of moths)
Drosophila (a genus of flies)
Campsicnemus mirabilis (an extinct species of fly)
Campsicnemus brevipes (a species of fly)
Paralopostega (a genus of moths)
Mestolobes (a genus of moths)
Hypena (a genus of moths)
Orthomecyna (a genus of moths)
Helicoverpa (a genus of moths)
Scotorythra (a genus of moths)
Genophantis (a genus of moths)
Tritocleis (a genus of moths)
Eurynogaster (a genus of flies)
Kamehameha butterfly (a.k.a. Pulelehua) (Vanessa tameamea)
Green Hawaiian blue (Udara blackburni)
Longhead yellow-faced bee (a.k.a. the Hawaiian yellow-faced bee) (Hylaeus longiceps)
Thaumatogryllus (a genus of crickets)
Wēkiu bug (Nysius wekiuicola)
Drosophila sharpi (a rare species of fly)
Koʻolau spurwing long-legged fly (an extinct species of fly
Lanai pomace fly (an extinct species of fly)
Phyllococcus oahuensis (a species of mealybug)
Megalagrion (a genus of damselfly)
Clavicoccus (a genus of mealybug)
Dryophthorus distinguendus (a species of weevil)
Laysan weevil (an extinct species of weevil)
Rhyncogonus bryani (an extinct species of weevil)
Manduca blackburni (an endangered species of hawkmoth)
Thyrocopa (a genus of moths)
Caconemobius nori (a species of cricket)
Caconemobius howarthi (a species of cricket)
Caconemobius schauinslandi (a species of cricket)
Caconemobius varius (a species of cricket)

Crustaceans

Atyoida bisulcata (a freshwater shrimp)
Halocaridina (a genus of marine and brackish water shrimp)
Hawaiian river shrimp (Macrobrachium grandimanus)

Spiders

Ariamnes makue (a species of spider)
Happy face spider (Theridion grallator)
Kauaʻi cave wolf spider (Adelocosa anops) - endangered
Orsonwelles, a genus of 13 species, each endemic to a single island
Nihoa (a genus of spiders)
Lycosa hawaiiensis (a species of spider)

Gastropods

Gastropods are snails.

Oahu tree snails (Achatinella) - threatened, several already extinct
Auriculella (a genus of land snails) - threatened, several already extinct
Amastra (a genus of land snails) - many species extinct
Carelia (a genus of land snails) - entire genus extinct
Erinna (a genus of freshwater snails) - one vulnerable species, the other possibly extinct
Gulickia alexandri (a land snail) - critically endangered
Newcombia (a genus of land snails) - threatened, one already extinct
Neritina granosa (a freshwater snail) - vulnerable
Perdicella (a genus of land snails) - threatened, several already extinct
Partulina (a genus of land snails) - threatened, several already extinct

Marine animals

Marine fishes

Cnidarians

Finger coral (Porites compressa)
Thick finger coral (Porites duerdeni)
Brigham's coral (Porites brighami)
Molokaʻi cauliflower coral (Pocillopora molokensis)
Irregular rice coral (Montipora dilatata)
Blue rice coral (Montipora flabellata)
Sandpaper or Ringed rice coral (Montipora patula)
Verril's lump coral (Psammocora verrilli)
Serpentine cup coral (Eguchipsammia serpentina)
Grand black coral (Antipathes grandis)
Bicolor gorgonian (Acabaria bicolor)
Small knob leather coral (Sinularia molokaiensis)

Plants

The Hawaiian Islands are home to dozens of endemic species and subspecies of plants, including endemic genera × Argyrautia, Argyroxiphium, Brighamia, Clermontia, Cyanea, Delissea, Dissochondrus, Dubautia, Haplostachys, Helodeaster, Hesperomannia, Hibiscadelphus, Hillebrandia, Isodendrion, Kokia, × Lindsaeosoria, Lipochaeta, Neraudia, Nothocestrum, Nototrichium, Pteralyxia, Remya, Rockia, Schiedea, Stenogyne, Touchardia, Trematolobelia, and Wilkesia.

The following list of endemic vascular plants is from Plants of the World Online, current and complete as of March 2025. Plants are listed alphabetically by order and family.

Lycopods

Lycopodiaceae

Selaginellaceae

Selaginella deflexa Brack.
Selaginella menziesii (Hook. & Grev.) Spring
Selaginella sandvicensis Baker

Ferns

Aspleniaceae

Cyatheae

Cibotium chamissoi Kaulf. – Oahu
Cibotium glaucum (Sm.) Hook. & Arn.
Cibotium × heleniae D.D.Palmer
hāpuʻu ʻiʻi or Hawaiian tree fern (Cibotium menziesii Hook.)
Cibotium nealiae Degen. – Kauai

Dennstaedtiaceae

Hypolepis hawaiiensis Brownsey
Microlepia × adulterina W.H.Wagner (M. setosa × M. speluncae) – Oahu
Microlepia setosa var. mauiensis (W.H.Wagner) Miles K.Thomas – Maui and Hawaii
Pteridium decompositum (Gaudich.) Christenh.

Gleicheniaceae

Dicranopteris linearis f. emarginata (T.Moore) W.H.Wagner
Diplopterygium pinnatum (Kunze) Nakai
Sticherus owhyhensis (Hook.) Ching

Hymenophyllaceae

Lindsaeaceae

× Lindsaeosoria W.H.Wagner (Lindsaea × Odontosoria)
- × Lindsaeosoria flynnii W.H.Wagner – Kauai

Marattiaceae

Marattia douglasii (C.Presl) Baker

Ophioglossaceae

† Botrychium subbifoliatum Brack.

Polypodiaceae

Psilotaceae

Psilotum × intermedium W.H.Wagner (P. complanatum × P. nudum)

Pteridaceae

Alismatales

Hydrocharitaceae

Halophila hawaiiana Doty & B.C.Stone

Apiales

Apiaceae

Peucedanum sandwicense Hillebr.
Sanicula kauaiensis H.St.John
Sanicula mariversa Nagata & S.M.Gon
Sanicula purpurea H.St.John & Hosaka
Sanicula sandwicensis A.Gray
Spermolepis hawaiiensis H.Wolff

Araliaceae

Pittosporaceae

Arecales

Arecaceae

Asparagales

Asparagaceae

Golden hala pepe (Dracaena aurea H.Mann) – Kauai
Lanai hala pepe (Dracaena fernaldii (H.St.John) Jankalski) – Lanai
Waianae Range hala pepe (Dracaena forbesii (O.Deg.) Jankalski) – Oahu
Royal hala pepe (Dracaena halapepe (H.St.John) Jankalski) – Oahu
Dracaena halemanuensis Jankalski
Hawai'i hala pepe (Dracaena konaensis (H.St.John) Jankalski) – Hawaii
Maui hala pepe (Dracaena rockii (H.St.John) Jankalski) – Molokai, Maui

Asteliaceae

Astelia argyrocoma A.Heller ex Skottsb. – Kauai
Puaʻakuhinia (Astelia menziesiana Sm.)
Pa'iniu (Astelia waialealae Wawra) – Kauai

Iridiaceae

Sisyrinchium acre H.Mann – eastern Maui and Hawaii

Orchidaceae

Hawai'i jewel orchid (Anoectochilus sandvicensis Lindl.)
Hawai'i widelip orchid (Liparis hawaiensis H.Mann)
Hawai'i bog orchid (Peristylus holochila (Hillebr.) N.Hallé)

Asterales

Asteraceae

Campanulaceae

Goodeniaceae

Scaevola × cerasifolia Skottsb. (S. gaudichaudiana × S. mollis)
Scaevola chamissoniana Gaudich.
Scaevola coriacea Nutt.
Scaevola gaudichaudiana Cham.
Scaevola gaudichaudii Hook. & Arn.
Scaevola glabra Hook. & Arn.
Scaevola hobdyi W.L.Wagner – western Maui
Scaevola kilaueae O.Deg.
Scaevola mollis Hook. & Arn.
Scaevola procera Hillebr.

Boraginales

Boraginaceae

Nama sandwicensis A.Gray

Brassicales

Brassicaceae

Lepidium arbuscula Hillebr.
Lepidium bidentatum var. owaihiense (Cham. & Schltdl.) Fosberg
† Lepidium bidentatum var. remyi (Drake) Fosberg – Hawaii; last recorded in 1949.
Lepidium orbiculare H.St.John
Lepidium serra H.Mann

Capparaceae

Capparis sandwichiana DC.

Caryophyllales

Amaranthaceae

Caryophyllaceae

Nyctaginaceae

Boerhavia herbstii Fosberg
Ceodes wagneriana (Fosberg) E.F.S.Rossetto & Caraballo – Kauai
Rockia Heimerl
- Rockia sandwicensis (Hillebr.) Heimerl

Phytolaccaceae

Phytolacca sandwicensis Endl.

Polygonaceae

Rumex albescens Hillebr.
Rumex giganteus W.T.Aiton
Rumex skottsbergii O.Deg. & I.Deg.

Portulacaceae

Portulaca molokiniensis Hobdy
Portulaca sclerocarpa A.Gray
Portulaca villosa Cham.

Cornales

Hydrangeaceae

Kanawao (Hydrangea arguta (Gaudich.) Y.De Smet & Granados)

Cucurbitales

Begoniaceae

Hillebrandia Oliv.
- Hillebrandia sandwicensis Oliv.

Cucurbitaceae

Ericales

Ebenaceae

Diospyros hillebrandii (Seem.) Fosberg – Kauai and Oahu
Diospyros sandwicensis (A.DC.) Fosberg

Ericaceae

Vaccinium calycinum Sm.
Vaccinium dentatum Sm.
Vaccinium reticulatum Sm.

Pentaphylacaceae

Eurya sandwicensis A.Gray

Primulaceae

Sapotaceae

Planchonella sandwicensis (A.Gray) Pierre
Planchonella spathulata (Hillebr.) Pierre

Fabales

Fabaceae

Gentianales

Apocynaceae

Gentianaceae

Schenkia sebaeoides (A.Gray) Griseb.

Loganiaceae

Rubiaceae

Geraniales

Geraniaceae

Geranium arboreum A.Gray – Maui
Geranium cuneatum Hook. – western and central Hawaii
Geranium hanaense A.C.Medeiros & H.St.John – eastern Maui
Geranium hillebrandii Aedo & Muñoz Garm. – northwestern Maui
Geranium kauaiense (Rock) H.St.John – Kauai
Geranium multiflorum A.Gray – eastern Maui

Gunnerales

Gunneraceae

Gunnera kauaiensis Rock – Kauai
Gunnera petaloidea Gaudich.

Huerteales

Dipentodontaceae

Perrottetia sandwicensis A.Gray
Perrottetia wichmaniorum Lorence & W.L.Wagner – Kauai

Isoetales

Isoetaceae

Isoetes hawaiiensis W.C.Taylor & W.H.Wagner – Maui and Hawaii

Lamiales

Gesneriaceae

Lamiaceae

Oleaceae

Notelaea sandwicensis (A.Gray) Hong-Wa & Besnard

Plantaginaceae

Plantago hawaiensis (A.Gray) Pilg.
Plantago pachyphylla A.Gray
Plantago princeps Cham. & Schltdl.

Scrophulariaceae

Myoporum stellatum (G.L.Webster) O.Deg. & I.Deg.

Laurales

Lauraceae

Cryptocarya mannii Hillebr. – Kauai and Oahu
Lindsaea knudsenii Hillebr. – Kauai

Liliales

Smilacaceae

Smilax melastomifolia Sm.

Malpighiales

Euphorbiaceae

Phyllanthaceae

Antidesma × kapuae Rock (A. platyphyllum × A. pulvinatum) – Hawaii: South Kona
Antidesma platyphyllum H.Mann
Antidesma pulvinatum Hillebr.
Flueggea neowawraea W.J.Hayden
Phyllanthus distichus Hook. & Arn.

Salicaceae

Xylosma crenata (H.St.John) H.St.John – Kauai
Xylosma hawaiensis Seem.

Violaceae

Malvales

Malvaceae

Thymelaeaceae

Myrtales

Myrtaceae

Piperales

Piperaceae

Poales

Cyperaceae

Joinvilleaceae

Joinvillea ascendens Gaudich. ex Brongn. & Gris

Juncaceae

Luzula hawaiiensis Buchenau

Poaceae

Oxalidales

Elaeocarpaceae

Elaeocarpus bifidus Hook. & Arn. – Kauai and Oahu

Ranunculales

Papaveraceae

Argemone glauca (Nutt. ex Prain) Pope

Ranunculaceae

Ranunculus hawaiensis A.Gray
Ranunculus mauiensis A.Gray

Rosales

Rhamnaceae

Alphitonia ponderosa Hillebr.
Colubrina oppositifolia Brongn. ex H.Mann
Gouania hillebrandii Oliv. ex Hillebr.
Gouania meyenii Steud.
Gouania vitifolia A.Gray