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The genus ''Gallotia'' are the lacertids (wall lizards) of the Canary Islands. This genus consists of a group that has been evolving there ever since the first islands emerged from the sea over 20 million years ago. The endemic species and subspecies of this group have a number of characteristics that make them quite special within their family (Lacertidae); their only close relatives are the sandrunner lizards (''Psammodromus'') of the western Mediterranean region. ''Gallotia'' are characteristic for eating significant quantities of plants, and for several lineages having evolved insular gigantism. ==Systematics and biogeography== This genus can be broadly divided into two groups - lineages originating from the colonization of the earliest Canary Islands of Lanzarote, Fuerteventura and Gran Canaria, probably between 10-20 million years ago, and a lineage that colonised the younger western islands probably less than 10 million years. ago (Cox et al., 2010). Both lineages contain large and small species. MtDNA analyses indicate that Lanzarote and Fuerteventura were colonized first and this led to the small body-sized ''G.atlantica'' which is present today (Cox et al., 2010). Gran Canaria was the next island to have been colonized from Lanzarote/Fuerteventura, giving rise to the large body-sized species, ''G. stehlini'' (Cox et al., 2010). Finally, the clade that colonized the younger western islands was likely to have originated from Lanzarote/Fuerteventura. This western island clade diverged into two groups, all of which colonized Tenerife, La Palma, La Gomera and El Hierro, leading to 1) a medium-bodied (e.g., ''G. caesaris'' from El Hierro) and 2) a large bodied "giant" species (e.g., ''G. simonyi'' from El Hierro) on each of these islands (note that ''G. intermedia'' from Tenerife belongs to the "giant" group, but present-day individuals are not that large). The giant species now exist, at best, in small relict populations, while ''G. auritae'' may be extinct on La Palma. (These patterns are based on analyses of mtDNA alone, and may be refined in the future after analyses of the nuclear genome).It is well possible that remains of extinct giant forms will eventually be discovered on Fuerteventura & Lanzarote. Prehistoric remains were assigned to the taxa ''G. goliath'' and ''G. maxima'', the former supposedly occurring on several islands, the latter only on Tenerife. It was eventually determined, however, that ''G. maxima'' is a junior synonym of ''G. goliath'', and that the latter was very close to ''G. simonyi''; supposed ''goliath'' specimens from El Hierro, La Gomera, and La Palma are probably just extremely large individuals of, respectively, ''G. simonyi'', ''G. bravoana'', and ''G. auaritae'' (Barahona ''et al.'' 2000). However, a mummified giant specimen from Tenerife yielded ancient DNA remains, and by analysis of this, it was concluded that ''G. goliath'' is a valid species that probably was restricted to Tenerife, and apparently was closer to ''G. intermedia'' than to ''G. simonyi'' (Maca-Meyer ''et al.'' 2003). Basal group *''Gallotia atlantica'' - Atlantic Lizard * *''Gallotia atlantica atlantica'' * *''Gallotia atlantica mahoratae'' *''Gallotia stehlini'' - Gran Canaria Giant Lizard Western clade Large species *''Gallotia simonyi'' * *''Gallotia simonyi simonyi'' - Roque Chico de Salmor Giant Lizard, extinct (c.1930s) * *''Gallotia simonyi machadoi'' - El Hierro Giant Lizard *''Gallotia bravoana'' - La Gomera Giant Lizard, formerly ''G. (simonyi) gomerana'' and ''G. simonyi bravoana'' (Miras & Pérez-Mellado 2005a) *''Gallotia auaritae'' - La Palma Giant Lizard *''Gallotia goliath'' - Tenerife Giant Lizard, subfossil; includes ''G. maxima'' *''Gallotia intermedia'' - Tenerife Speckled Lizard Small species *''Gallotia caesaris'' - Boettger's Lizard * *''Gallotia caesaris caesaris'' * *''Gallotia caesaris gomerae'' *''Gallotia galloti'' - Tenerife Lizard or Western Canaries Lizard * *''Gallotia galloti eisentrauti'' * *''Gallotia galloti galloti'' * *''Gallotia galloti insulanagae'' * *''Gallotia galloti palmae'' 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「Gallotia」の詳細全文を読む スポンサード リンク
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