Horseshoe bat

In the broad sense, it is a general term for animals belonging to the order Chiroptera of the class Mammalia, family Rhinolophidae, and in the narrow sense, it refers to one of these species. The members of this family, Rhinolophidae, are distributed in Eurasia, Africa, and Australia. It consists of one genus and 69 species, and the oldest fossils are known from the Eocene of Europe. The species Rhinolophus ferrumequinum is distributed in Eurasia and Africa, and in Japan it lives from Hokkaido to Yakushima. The forearm length is 59 to 62 mm, and the head and body length is 62 to 73 mm. It has a nasal lobe on the face, pointed tips of the ears, no tragus, prominent palps, and wide tail membrane and wings. The nasal lobe is divided into three parts: a horseshoe-shaped front part, a triangular rear part, and a saddle-shaped middle part. The thorax is sturdy, and the front mandibles are cartilaginous and separate from the surrounding bones. They usually live alone or in groups of a few, sometimes up to 100, in caves, abandoned mines, and occasionally in human dwellings. They fly slowly at low altitudes and prey on large insects such as scarab beetles. They give birth to a single baby in early summer. The naked newborn is constantly held on the parent's chest until it grows hair and becomes two-thirds the size of the parent, and they do not form groups of infants like the lesser horseshoe bat R. cornutus .

[Yoshiyuki Mizuko]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

広義には哺乳(ほにゅう)綱翼手目キクガシラコウモリ科に属する動物の総称で、狭義にはそのうちの1種をさす。この科Rhinolophidaeの仲間は、ユーラシア、アフリカおよびオーストラリアに分布する。1属69種からなり、最古の化石はヨーロッパの始新世から知られる。種のキクガシラコウモリRhinolophus ferrumequinumはユーラシアとアフリカに分布し、日本では北海道から屋久島(やくしま)まで生息する。前腕長59～62ミリメートル、頭胴長62～73ミリメートル。顔に鼻葉をもち、耳介の先はとがり、耳珠を欠き、迎珠が顕著で、尾膜、翼が幅広い。鼻葉は馬蹄(ばてい)状の前部、三角状の後部、鞍(くら)状の中部の3部に分かれる。胸郭は頑丈で、前顎骨(ぜんがくこつ)は軟骨状で周りの骨から遊離する。洞窟(どうくつ)、廃坑、まれに人家などに普通単独か数頭、ときに100頭ほどの群れですむ。低空をゆっくり飛行しながら、コガネムシなどの大きい昆虫を捕食する。初夏に1子を産む。赤裸で生まれた新生子は、毛が生えて親の3分の2大になるまで親の胸に絶えず抱かれており、コキクガシラコウモリR. cornutusのように幼児集団をつくらない。

［吉行瑞子］

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