Question: Hibiscus waimeae, is a species of flowering plant in the okra family, Malvaceae, that is endemic to the island of Kauaʻ i in Hawaii, H. arnottianus" of Oʻ ahu and Molokaʻ i and "H. waimeae", have white flowers, and are the only of how many species of hibiscus, regarded as native to Hawaii?
Context: Hibiscadelphus distans (Kauai hau kuahiwi) is an extremely rare species of flowering plant in the mallow family, Malvaceae, that is endemic to the island of Kauaʻ i in Hawaii.  It is known as hau kuahiwi in Hawaiian, which means "upland "Hibiscus tiliaceus"."  It is a bush or small tree with heart-shaped leaves and yellow flowers and grows at between 1,000 and 1,800 feet (300 and 550 m) in the remnants of native dry forests.  Despite its rarity, it is believed to be the only surviving species in the genus "Hibiscadelphus" which is only known from Hawaii, the other five species having recently become extinct in the wild, some being known from only a single plant. Gouania vitifolia (also known as Oʻ ahu chewstick) is an endangered species flowering plant in the buckthorn family, Rhamnaceae that is endemic to Hawaii.  It is a climbing shrub or woody vine.  "G. vitifolia" inhabits dry, coastal mesic, and mixed mesic forests on Oʻ ahu (Waiʻ anae Mountains), and the Island of Hawaiʻ i (Kaʻ ū district).  In 2007 there were no more than 64 plants left on Oahu and two populations with a total "numbering in the tens" on Hawaii. Urera kaalae, opuhe, is a species of flowering plant in the nettle family, Urticaceae, that is endemic to the island of Oʻ ahu in Hawaii.  It inhabits slopes and gulches in mesic forests at elevations of 300 - .  Currently it is restricted to the southern and central parts of the Waiʻ anae Mountains.  Associated plants include maile ("Alyxia oliviformis"), hame ("Antidesma platyphyllum"), "Asplenium kaulfusii", "Athyrium" spp., ʻ āwikiwiki ("Canavalia" spp.) , pāpala ("Charpentiera" spp.) , ʻ akoko ("Euphorbia" spp.) , poʻ olā ("Claoxylon sandwicense"), ēlama ("Diospyros hillebrandii"), "Doryopteris" spp., ʻ ieʻ i.e. ("Freycinetia arborea"), manono ("Hedyotis acuminata"), "Hibiscus" spp., olopua ("Nestegis sandwicensis"), māmaki ("Pipturus albidus"), hala pepe ("Pleomele" spp.) , ʻ ālaʻ a ("Pouteria sandwicensis"), kōpiko ("Psychotria" spp.) , heuhiuhi ("Senna gaudichaudii"), aʻ iaʻ i ("Streblus pendulinus"), ōpuhe ("Urera glabra"), and maua ("Xylosma hawaiiense").  It is threatened by habitat loss. Nothocestrum latifolium, commonly known as broadleaf ʻ aiea, is a species of flowering plant in the nightshade family, Solanaceae, that is endemic to Hawaiʻ i.  It can be found in dry and mesic forests at elevations of 460 – on the islands of Maui, Molokaʻ i, Lānaʻ i, Oʻ ahu, and Kauaʻ i.  Broadleaf ʻ aiea is threatened by habitat loss.  The CDP of ʻ Aiea on Oʻ ahu was named after this species. Hibiscus waimeae (white Kauai rosemallow, Hawaiian: "" , or ) is a species of flowering plant in the okra family, Malvaceae, that is endemic to the island of Kauaʻ i in Hawaii.  It is a small gray-barked tree, reaching a height of 6 - and a trunk diameter of 0.3 m .  The flowers last for a single day, starting out white and fading to pink in the afternoon.  "H. arnottianus" of Oʻ ahu and Molokaʻ i and "H. waimeae" are the only Hawaiian hibiscuses that have white flowers.  "H. waimeae" inhabits coastal mesic, mixed mesic, and wet forests at elevations of 250 – . Swamp rosemallow (Hibiscus grandiflorus) is a species of flowering plant in the okra family, Malvaceae, that is endemic to the Southeastern United States. Vaccinium reticulatum, known as ʻ Ōhelo ʻ ai in Hawaiian, is a species of flowering plant in the heather family, Ericaceae, that is endemic to Hawaii.  It grows at altitudes of 640 - on lava flows and freshly disturbed volcanic ash on Maui and Hawaiʻ i, and less commonly on Kauaʻ i, Oʻ ahu, and Molokaʻ i.  Adaptations to volcanic activity include the ability to survive ash falls of over 25 cm depth. Sida fallax, known as yellow 'ilima, or in Hawaiian, ʻ ilima, is a species of herbaceous flowering plant in the "Hibiscus" family, Malvaceae, that occurs on some Pacific Islands.  The flowers are small, 0.75 - in diameter, have five petals, and are a golden yellow in color.  Plants may be erect or prostrate and are found in drier areas in sandy soils, often near the ocean. " ʻ Ilima" is the symbol of Laloimehani and is the flower for the island of Oʻ ahu. Hawaiian hibiscus are seven species of hibiscus regarded as native to Hawaii.  The yellow hibiscus is Hawaii's state flower.  Although tourists regularly associate the hibiscus flower within experiences visiting the US state of Hawaii, and the plant family Malvaceae includes a relatively large number of species that are native to the Hawaiian Islands, those flowers regularly observed by tourists are generally not the native hibiscus flowers.  Most commonly grown as ornamental plants in the Islands are the Chinese hibiscus ("Hibiscus rosa-sinensis") and its numerous hybrids. Neraudia melastomifolia, known as Maʻ aloa in Hawaiian, is a species of flowering plant in the nettle family, Urticaceae, that is endemic to Hawaii.  It is a shrub or small tree, reaching a height of up to 5 m .  "N. melastomifolia" inhabits coastal mesic, mixed mesic, and wet forests at elevations of 270 - on Kauaʻ i Oʻ ahu, Molokaʻ i, and Maui.  It is threatened by habitat loss.
Answer: seven