Alligator gar Atractosteus spatula are ray-finned euryhaline fish related to bowfin in the infraclass Holostei ho`-las-te-i. The fossil record traces their existence to the Early Cretaceous over a hundred million years ago. They are the largest species in the gar family, and among the largest freshwater fishes in North America. Gars are often referred to as `primitive fishes`, or `living fossils` because they have retained some morphological characteristics of their earliest ancestors, such as a spiral valve intestine which is also common to the digestive system of sharks, and the ability to breathe both air and water. Their common name was derived from their resemblance to American alligator, particularly their broad snout and long sharp teeth. Anecdotal evidence in several scientific reports suggest that an alligator gar can grow up to 10 ft 3.0 m in length and weigh as much as 300 lb 140 kg; however in 2011 the largest alligator gar ever caught and officially recorded was 8 ft 5 1âÂâ4 in 2.572 m long, weighed 327 lb 148 kg, and was 47 in 120 cm around the girth.
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83769871
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Drzaribu
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授權類型 | 尺寸 | 像素 | 格式 | 點數 | |
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標準授權 | XS | 480 x 318 | JPG | 13 | |
標準授權 | S | 800 x 530 | JPG | 15 | |
標準授權 | M | 2128 x 1409 | JPG | 18 | |
標準授權 | L | 2747 x 1819 | JPG | 20 | |
標準授權 | XL | 3696 x 2448 | JPG | 22 | |
標準授權 | MAX | 4256 x 2819 | JPG | 23 | |
標準授權 | TIFF | 5227 x 3462 | TIF | 39 | |
進階授權 | WEL | 4256 x 2819 | JPG | 88 | |
進階授權 | PEL | 4256 x 2819 | JPG | 88 | |
進階授權 | UEL | 4256 x 2819 | JPG | 88 |
XS
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M
L
XL
MAX
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WEL
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標準授權 | 480 x 318 px | JPG | 13 點 |
標準授權 | 800 x 530 px | JPG | 15 點 |
標準授權 | 2128 x 1409 px | JPG | 18 點 |
標準授權 | 2747 x 1819 px | JPG | 20 點 |
標準授權 | 3696 x 2448 px | JPG | 22 點 |
標準授權 | 4256 x 2819 px | JPG | 23 點 |
標準授權 | 5227 x 3462 px | TIF | 39 點 |
進階授權 | 4256 x 2819 px | JPG | 88 點 |
進階授權 | 4256 x 2819 px | JPG | 88 點 |
進階授權 | 4256 x 2819 px | JPG | 88 點 |