日本近海で採集されたマンボウ属(Mola spp. A and B)の形態異常個体

アクセス数 : 1226
ダウンロード数 : 175

今月のアクセス数 : 0
今月のダウンロード数 : 0
File
JGradSchBiospSciHU_48_9.pdf 1.49 MB 種類 : fulltext
Title ( jpn )
日本近海で採集されたマンボウ属(Mola spp. A and B)の形態異常個体
Title ( eng )
On the abnormally morphological forms in Mola sunfish (Mola spp. A and B) taken from Japanese coastal waters
Creator
Sawai Etsuro
Yamanoue Yusuke
Hashimoto Hiroaki
Source Title
生物圏科学 : 広島大学大学院生物圏科学研究科紀要
Journal of the Graduate School of Biosphere Science, Hiroshima University
Volume 48
Start Page 9
End Page 17
Abstract
2007年6月から2008年12月までの日本近海におけるマンボウ属2種( Mola spp. A and B)の調査の中で(全145個体),胸鰭変形7個体,背鰭短縮2個体,背鰭軟条配置異常1個体,舵鰭臀部側欠損1個体,舵鰭欠損1個体,人為的な損傷3個体,精巣肥大2個体,幼形形態1個体を得た。これら異常がみられた18個体の内訳には先天的な奇形,捕食生物による損傷,人為的な損傷,寄生虫による変形などがあり,また長期間飼育された個体(1個体)は天然水域の個体と体形が異なる可能性が示唆された。人為的な損傷がみられた3個体と長期飼育された1個体を除く,天然水域で採集された異常個体(14個体)は採集された全体の約1割(14/145)で,ある程度は天然水域にも存在するものと推測された。
Of 145 ocean sunfish specimens obtained from Japanese coastal waters between June 2007 and December 2008, morphologically abnormal forms were confirmed in a total of 18 specimens. Seven had transformed pectoral fins; two had shortened dorsal fins; one had abnormally arranged dorsal soft rays; one was missing the lower part of the clavus; one was missing the whole clavus; three had partially damaged bodies or fins, probably because of artificial cutting; two had hypertrophied testes; and one was a young fish in the juvenile-specific morphological form. These abnormal forms were thought to have occurred as a consequence of congenital malformation or damage by predation, parasites, humans, or other factors. One suffered a transformation in body shape from a natural form, probably because it was reared for a long period of time in an aquarium. According to the frequency of non-artifically abnormal individuals (ca. 10%, 14/145), the occurrence of abnormalities is not rare in natural populations.
Keywords
異常個体
外部形態
飼育個体
精巣肥大
マンボウ属
abnormal form
external morphology
hypertrophied testes
Mola spp. A and B
reared specimens
NDC
Zoology [ 480 ]
Language
jpn
Resource Type departmental bulletin paper
Publisher
広島大学大学院生物圏科学研究科
Date of Issued 2009-12-25
Publish Type Version of Record
Access Rights open access
Source Identifier
[ISSN] 1348-1371
[NCID] AA11768091
[NAID] 120005319648