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Early Miocene to Present | status = VU | status_system = IUCN3.1 | status_ref = | image = Manta birostris-Thailand4.jpg | image_width = 250px | image_caption = | regnum = Animalia | phylum = Chordata | classis = Chondrichthyes | subclassis = Elasmobranchii | ordo = Myliobatiformes | subordo = Myliobatidae | familia = Mobulidae | genus = ''Manta'' | species = ''M. birostris'' | binomial = ''Manta birostris'' | binomial_authority = Walbaum, 1792 | range_map = Cypron-Range Manta birostris.svg | range_map_width = | range_map_alt = | range_map_caption = Range of the giant oceanic manta ray | synonyms = *''Manta hamiltoni'' Hamilton & Newman, 1849 *''Raja birostris'' Donndorff, 1798 }} The giant oceanic manta ray (''Manta birostris'') is a species of ray in the family Mobulidae, and the largest type of ray in the world. They are circumglobal and are typically found in tropical and subtropical waters, but can also be found in temperate waters. ==Description== The giant oceanic manta ray can grow to a disc size of up to with a weight of about but average size commonly observed is .〔http://www.mantatrust.org/about-mantas/mantas-at-a-glance/〕 It is dorsoventrally flattened and has large, triangular pectoral fins on either side of the disc. At the front, it has a pair of cephalic fins which are forward extensions of the pectoral fins. These can be rolled up in a spiral for swimming or can be flared out to channel water into the large, forward-pointing, rectangular mouth when the animal is feeding. The teeth are in a band of 18 rows and are restricted to the central part of the lower jaw. The eyes and the spiracles are on the side of the head behind the cephalic fins, and the gill slits are on the ventral (under) surface. It has a small dorsal fin and the tail is long and whip-like. The manta ray does not have a spiny tail as do the closely related devil rays (''Mobula'' spp.) but has a knob-like bulge at base of its tail.〔"Field guide to the identification of Mobulid rays (Mobulidae)", Guy Stevens, Manta Trust, 2011.〕 The skin is smooth with a scattering of conical and ridge-shaped tubercles. The colouring of the dorsal (upper) surface is black, dark brown, or steely blue, sometimes with a few pale spots and usually with a pale edge. The ventral surface is white, sometimes with dark spots and blotches. The markings can often be used to recognise individual fish. ''Manta birostris'' is similar in appearance to ''Manta alfredi'' and the two species may be confused as their distribution overlaps. However there are distinguishing features. 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「Giant oceanic manta ray」の詳細全文を読む スポンサード リンク
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