Matamata - Again (English spelling) matamata

This turtle belongs to the order Testudins, family Chelonidae, class Reptilia. There is only one species in one genus, and it is found in Venezuela, Guiana, and northern and central Brazil. It is the largest of its kind in the family, reaching a carapace length of about 40 centimeters. Its unusual English name, Matamata, comes from the local word meaning "skin," and it is known as one of the strangest turtles in terms of morphology. Its carapace is flat, with each carapace rising in a mountain shape, and the marginal carapace is sharpened like a saw at the rear. The plastron is narrow. Its head is triangular and flat, with a snout that extends like a thin tube and has nostrils. Its mouth is large, but its jaws are weak. Its neck is long and wide, and its skin has many tufts of decoration. It lies on the bottom of stagnant rivers, and when fish approach, attracted by its decorations that look like food, it swallows them with its large mouth along with the water. During the day, it hides in the shade, but algae grow on its shell, making it look like a rock on the bottom of the water.

[Takahiro Matsui]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

爬虫(はちゅう)綱カメ目ヘビクビガメ科のカメ。1属1種で、ベネズエラ、ギアナ、ブラジル北部・中部に分布し、同科のなかでは大形で甲長約40センチメートルに達する。マタマタという風変わりな英名は「皮膚」を意味する現地語に由来し、形態的にもカメではもっとも奇妙な種として知られる。甲は扁平(へんぺい)で、背甲の各甲板が山形に隆起し、縁甲板は後部で鋸歯(きょし)状にとがる。腹甲は幅が狭い。頭部は三角形で平たく、吻(ふん)部は細い管状に伸び鼻孔が開く。口は大きいが、あごの力は弱い。頸(けい)部は長くて幅広く、皮膚に多くの房状の飾りがある。よどんだ河川の水底に横たわり、餌(えさ)のようにみえる飾りに誘われて近寄る魚を、大きな口で水とともに飲み込む。日中は物陰に隠れているが、甲には藻類が付着して水底の石のようにみえる。

［松井孝爾］

出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例