Sarcococca and Emmenopterys can both be found in southeastern Asia?
yes
Sarcococca
Sarcococca (sweet box or Christmas box) is a genus of 16–20 species of flowering plants in the box family Buxaceae, native to eastern and southeastern Asia and the Himalayas.
 They are slow-growing, monoecious, evergreen shrubs 1 - tall.
 The leaves are borne alternately, 3–12 cm long and 1–4 cm broad.
 They bear fragrant flowers, often in winter.
 The fruit is a red or black drupe containing 1–3 seeds.
 Some species are cultivated as groundcover or low hedging in moist, shady areas.
 The basic chromosome number for genus is 14 (2n = 28).
Emmenopterys
Emmenopterys is a genus of flowering plants in the Rubiaceae family.
 The genus is found in China, Burma, Thailand, and Vietnam.
Southeast Asia
Southeast Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia.
 Southeast Asia is bordered to the north by East Asia, to the west by South Asia and Bay of Bengal, to the east by Oceania and Pacific Ocean, and to the south by Australia and Indian Ocean.
 The region is the only part of Asia that lies within the Southern Hemisphere.
 In contemporary definition, Southeast Asia consists of two geographic regions: Lygodium japonicum
Lygodium japonicum is a species of fern that is known by the common names vine-like fern and Japanese climbing fern.
 It is native to eastern Asia, including Japan, Korea, southeastern Asia, and India, and eastern Australia.
 The fern is present in the southeastern United States and Puerto Rico as an introduced species. Hydrocotyle sibthorpioides
Hydrocotyle sibthorpioides is a small plant native to southeastern Asia.
 It is also referred to as lawn marshpennywort.
 "Hydrocotyle sibthorpioides" is a small dicot plant placed in the family Apiaceae.
 The common name for this plant is lawn marshpennywort, however there are several other synonyms used to identify "H. sibthorpioides".
 It grows in great abundance when the conditions are right.
 "Hydrocotyle sibthorpioides" originates in southeastern Asia but is slowly spreading in the United States along with other places around the world.
 It can grow in a wide variety of habitats.
 This plant has been used for several medical purposes in Asia. Rafflesia
Rafflesia is a genus of parasitic flowering plants.
 It contains approximately 28 species (including four incompletely characterized species as recognized by Willem Meijer in 1997), all found in southeastern Asia, mainly in Malaysia, Indonesia, Thailand and the Philippines. North American Atlantic Region
North American Atlantic Region is a floristic region within the Holarctic Kingdom identified by Armen Takhtajan and Robert F. Thorne, spanning from the Atlantic and Gulf coasts to the Great Plains and comprising a major part of the United States and southeastern portions of Canada.
 It is bordered by the Circumboreal floristic region in the north, by the Rocky Mountain and Madrean floristic regions in the west and by the Caribbean floristic region of the Neotropical Kingdom in the south of Florida.
 The flora of the region comprises two endemic monotypic families, Hydrastidaceae and Leitneriaceae, and is characterized by about a hundred of endemic genera (such as "Sanguinaria", "Leavenworthia", "Gillenia", "Neviusia", "Dionaea", "Yeatesia", "Pleea").
 The degree of species endemism is very high, many species are Tertiary relicts, which survived the Wisconsin glaciation and are now concentrated in the Appalachians (esp.
 Blue Ridge Mountains) and the Ozarks.
 A number of genera ("Sarracenia", "Uvularia" etc.) are shared only with the Canadian floristic province of the Circumboreal region.
 Moreover, as has long been noted (e.g. by Joseph Gerhard Zuccarini and especially by Asa Gray), a large number of relict genera ("Liriodendron", "Hamamelis", "Stewartia" etc.) are shared with the relatively distant Eastern Asiatic Region (comprising Japan and the east of China) and sometimes Southeast Asia.
 R. F. Thorne counted at least 74 genera restricted to eastern North America and Asia (mostly eastern and southeastern Asia).
 The fossil record indicates that during the Tertiary period a warm temperate zone extended across much of the Northern Hemisphere, linking America to Asia. Xenophrys
Xenophrys is a genus of amphibians in the Megophryidae family.
 They are found in southeastern Asia (including China and northeastern India) to Borneo The genus has been found to be strongly polyphyletic, and awaiting a better solution, they have been included family "Megophrys".
 For the moment being, they are listed under their old genus in Wikipedia. Chrysopelea paradisi
Paradise tree snake or Paradise flying snake, "Chrysopelea paradisi", is a species of snake found in southeastern Asia.
 It can, like all species of its genus "Chrysopelea", glide by stretching the body into a flattened strip using its ribs.
 It is mostly found in moist forests and can cover a horizontal distance of about 100 metres in a glide from the top of a tree.
 Slow motion photography shows an undulation of the snake's body in flight while the head remains relatively stable, suggesting controlled flight.
 They are mildly venomous with rear fangs and also can constrict their prey, which consists of mostly lizards and bats. Cressa cretica
Cressa cretica is a species of flowering plant in the morning glory family.
 It is found in northern and central Africa, southern Europe and western Asia, as well as parts of southeastern Asia and Australia.
 It has long been used in traditional medicine and research has demonstrated that it has some therapeutic effects.