ギンザメ科 Chimaeridae Ghostsharks
,
Ratfishes
1 アマイロギンザメ（新称）
Chimaera fulva
Didier, Last and White, 2008 Southern
Chimaera
Specimens examined:
3 (SNFR 19258–19260; 510–830 mm TL; 298–398 mm body length, BDL), 637–950 m
depth.
Measurements (% BDL=% body length, dorsal edge
of gill opening to origin of dorsal caudal fin):
total length 208.5–219.9; precaudal length
122.4–127.3; snout–vent length 61.7–66.8; trunk length 38.3–41.7; pre-first
dorsal-fin length 27.6–31.9; pre-second dorsal-fin length 47.7–54.0; caudal dorsal margin 19.3–23.8; dorsal caudal fin,
maximum height 3.3–3.7; total caudal fin length including filament 89.2–90.7;
caudal ventral margin 28.5–30.4; ventral caudal fin, maximum height 3.4–3.8;
head length 23.9–28.6; preorbital length 9.5–12.4; first
dorsal-fin base length 17.6–21.7; dorsal-fin spine length 23.3; first
dorsal-fin maximum height 18.8–22.4; second dorsal-fin base length 77.2–80.1; pectoral-fin anterior margin 40.5–43.8;
pelvic-fin anterior margin 22.4–23.3; dorsal–caudal space 0 (no space between
dorsal and caudal fins); horizontal eye length 8.5–11.1; vertical eye height
6.0–7.4; total length of clasper from pelvic fin base
to tip 4.7–7.1 (two adolescent males: SNFR 19259, 708 mm TL and SNFR 19260, 510
mm TL).
計測形質（% BDL）：全長208.5–219.9；尾鰭前長122.4–127.3；総排泄孔前長61.7–66.8；躯幹部長38.3–41.7；第1背鰭前長27.6–31.9；第2背鰭前長47.7–54.0；尾鰭上葉長19.3–23.8；尾鰭上葉高3.3–3.7；尾鰭全長（糸状部を含む）89.2–90.7；尾鰭下葉長28.5–30.4；尾鰭下葉高3.4–3.8；頭長23.9–28.6；眼窩前長9.5–12.4；第1背鰭基底長17.6–21.7；背鰭棘長23.3；第1背鰭高18.8–22.4；第2背鰭基底長77.2–80.1；胸鰭長40.5–43.8；腹鰭長22.4–23.3；背鰭–尾鰭間隔0（隙間なし）；眼径8.5–11.1；眼高6.0–7.4；交接器全長4.7–7.1（未成熟の雄2個体：SNFR
19259，全長708
mmとSNFR
19260，全長510
mm）．
特 徴 躯幹部は短く，やや側扁する．尾部は腹鰭から尾鰭にかけて徐々に細長くなる．吻は比較的短く，尖る．眼は中庸大の楕円形で，弱い眼下の隆起がある．背鰭始部は胸鰭始部の直上に位置する．背鰭棘は長く，第1背鰭高とほぼ同じ長さで，棘の後縁上部は細かい鋸歯状．第2背鰭は基底が長く，高さはほぼ均一で，その始部は後方へ倒した背鰭棘の中心よりもやや前方に位置する．胸鰭は長く，幅広で，体側に折りたたんだとき後端は腹鰭の始部に達する．腹鰭は大きく，幅広で，ヘラ状．臀鰭は小さく，尾鰭の下葉とは切り込みによって離れる．尾鰭は短く，上葉，下葉ともに凸状でほぼ同じ高さ．尾部の糸状体は細く，長い．表皮は滑らかで薄く，剥がれやすい．頭部と体は銀色を帯びた桃色から淡褐色で，すべての鰭は淡褐色．
分 布 タスマニアを含むオーストラリア南部（水深780–1095
m；Didier
et al., 2008），インド洋南西部（水深637–950
m；本研究）．
備 考 計測方法はDidier
(2002)にしたがった．本種のほか，C.
notafricana
Kemper, Ebert, Compagno and Didier, 2010 がインド洋南西部から報告されている（Kemper
et al., 2010）．本種は模様のない銀色を帯びた桃色から淡褐色の体色をもつことによってC. notafricana（黒茶色で暗青色の縞模様がある）とは異なる．
（岡本）
Description
Trunk short and slightly compressed. Precaudal tail tapering evenly from pelvic fin to
caudal-fin base. Snout rather short, pointed. Eye moderately large, oval, with
weak subocular ridges. Dorsal-fin origin located
above pectoral-fin origin. Dorsal-fin spine long, its length subequal to first dorsal-fin height, posterior distal
margin of spine finely serrated. Second dorsal-fin long-based, mostly uniform
in height, its origin slightly anterior to midpoint of depressed dorsal-fin
spine. Pectoral fin long, broad, its posterior tip when adpressed
to body extending to origin of pelvic fin. Pelvic fin large, broad,
paddle-shaped. Anal fin small, separated by a small notch from ventral
caudal-fin margin. Caudal fin short, margins of dorsal
and ventral lobes strongly convex and subequal in
height. Caudal filament slender, very long. Skin smooth, thin, and deciduous.
Head and body silvery pink to pale brown, all fins pale brown.
Distribution Southern
Australia including
Remarks
Measurements followed Didier (2002). Besides
this species, C. notafricana
Kemper, Ebert, Compagno and Didier, 2010 was reported
from the southwestern
(M.
Okamoto)