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Fork-marked lemurs or fork-crowned lemurs are strepsirrhine primates; the four species comprise the genus ''Phaner''. Like all lemurs, they are native to Madagascar, where they are found only in the west, north, and east sides of the island. They are named for the two black stripes which run up from the eyes, converge on the top of the head, and run down the back as a single black stripe. They were originally placed in the genus ''Lemur'' in 1839, later moved between the genera ''Cheirogaleus'' and ''Microcebus'', and finally given their own genus in 1870 by British zoologist John Edward Gray. Only one species (''Phaner furcifer'') was recognized, until three subspecies described in 1991 were promoted to species status in 2001. New species may yet be identified, particularly in northeast Madagascar. Fork-marked lemurs are among the least studied of all lemurs and are some of the largest members of the family Cheirogaleidae, weighing around or more. They are the most phylogenetically distinct of the cheirogaleids, and considered a sister group to the rest of the family. Aside from their dorsal forked stripe, they have dark rings around their eyes, and large membranous ears. Males have a scent gland on their throat, but only use it during social grooming, not for marking territory. Instead, they are very vocal, making repeated calls at the beginning and end of the night. Like the other members of their family, they are nocturnal, and sleep in tree holes and nests during the day. Monogamous pairing is typical for fork-marked lemurs, and females are dominant. Females are thought to have only one offspring every two years or more. These lemurs live in a wide variety of habitats, ranging from dry deciduous forests to rainforests, and run quadrupedally across branches. Their diet consists primarily of tree gum and other exudates, though they may obtain some of their protein and nitrogen by hunting small arthropods later at night. Three of the four species are endangered and the other is listed as vulnerable. Their populations are in decline due to habitat destruction. Like all lemurs, they are protected against commercial trade under CITES Appendix I. ==Taxonomy== Fork-marked lemurs were first documented in 1839 by French zoologist Henri Marie Ducrotay de Blainville when he described the Masoala fork-marked lemur (''P. furcifer'') as ''Lemur furcifer''. The holotype is thought to be MNHN 1834-136, a female specimen taken from Madagascar by French naturalist Justin Goudot. The source of this specimen is unknown, but thought to be Antongil Bay. In 1850, French zoologist Isidore Geoffroy Saint-Hilaire moved the fork-marked lemurs to the genus ''Cheirogaleus'' (dwarf lemurs), but they were also commonly listed in the genus ''Microcebus'' (mouse lemurs). In 1870, British zoologist John Edward Gray assigned fork-marked lemurs to their own genus, ''Phaner'', after initially including them and the mouse lemurs in the genus ''Lepilemur'' (sportive lemurs). Although French naturalist Alfred Grandidier accepted Gray's new genus (while also lumping the other cheirogaleids in ''Cheirogaleus'' and illustrating the cranial similarities between cheirogaleids and ''Lepilemur'') in 1897, the genus ''Phaner'' was not widely accepted. In the early 1930s, zoologists Ernst Schwarz, Guillaume Grandidier, and others resurrected the name, citing characteristics that were intermediate between ''Cheirogaleus'' and ''Microcebus''. Until the late 20th century, there was only one recognized species of fork-marked lemur, although size and coloration differences had been noted previously. After comparing museum specimens, paleoanthropologist Ian Tattersall and physical anthropologist Colin Groves recognized three new subspecies in 1991: the Pale fork-marked lemur (''P. f. pallescens''), Pariente's fork-marked lemur (''P. f. parienti''), and the Amber Mountain fork-marked lemur (''P. f. electromontis''). In 2001, Groves elevated all four subspecies to species status based on noticeable color, size, and body proportion differences between the fragmented populations. Although Tattersall disagreed with this promotion, citing inadequate information for the decision, the arrangement is generally accepted. In December 2010, Russell Mittermeier of Conservation International and conservation geneticist Edward E. Louis, Jr. announced the possibility of a new species of fork-marked lemur in the protected area of Daraina in northeast Madagascar. In October, a specimen was observed, captured, and released, although genetic tests have yet to determine if it is in fact a new species. The specimen demonstrated a slightly different color pattern from other fork-marked lemur species. If shown to be a new species, they plan to name it after Fanamby, a key conservation organization working in that protected forest. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fork-marked lemur」の詳細全文を読む スポンサード リンク
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