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åçã«ããã€ã¿ãã¶ã¡ïŒGaleocerdo cuvierïŒã®å°Ÿãã¬çŽåã®åã蟌ã¿ã«ã€ããŠ
â æŠèŠ
ã€ã¿ãã¶ã¡ã®å°Ÿãã¬ä»ãæ ¹çŽåã®å°Ÿæéšäžé¢ã«ã¯ã暪åãã»äžæ¥æåœ¢ã®ã¹ãªããç¶ã®åã蟌ã¿ãèŠãããã
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ã»åç§°ïŒäžå°Ÿå窩ïŒãããã³ãããïŒ
ã»è±åïŒupper precaudal pitïŒå¥åïŒcaudal pitïŒprecaudal notchïŒ
ã»ä»åïŒfosse précaudale supérieure
ã»è¡åïŒchanfro pré-caudal
ã»äœçœ®ïŒå°Ÿãã¬ä»ãæ ¹ã®çŽåãå°ŸæéšïŒcaudal peduncleïŒäžé¢
ã»åœ¢ç¶ïŒæšªåãã»äžæ¥æåœ¢ïŒtransverse and crescenticïŒ
ãã®æ§é ã¯ãã€ã¿ãã¶ã¡å± Galeocerdo ãä»ã®ãµã¡ããèå¥ããããã®åé¡åŠç蚺æåœ¢è³ªã®äžã€ã§ããã
â 1. è§£ååŠçç¹å®
åœè©²ã®åã蟌ã¿ã®äœçœ®ã¯ãå°Ÿãã¬ãå§ãŸãããæåãå°ŸæéšïŒcaudal peduncleïŒã®äžé¢ã§ããã
ããã«èŠãããæšªåãã»äžæ¥æåœ¢ã®åã蟌ã¿ã¯ããµã¡é¡ã®è§£ååŠã«ãããŠãprecaudal pitïŒå°Ÿå窩ïŒããšåŒã°ããæ§é ã
âŒFishBase è§£ååŠçšèªéã«ããå®çŸ©
"A transverse or longitudinal notch on the caudal peduncle just in front of the caudal fin of sharks. Also called caudal pit."
ïŒãµã¡ã®å°Ÿãã¬ã®ããåãå°Ÿæéšã«ããæšªåããŸãã¯çžŠåãã®åã蟌ã¿ãcaudal pit ãšãåŒã°ããïŒ
åºå
žïŒ
fishbase.se/glossary/GlossarâŠ
âŒå€èšèªè¡šèš
æ¥æ¬èªïŒäžå°Ÿå窩ïŒå°Ÿå窩ïŒå°Ÿæå窩
è±èªïŒupper precaudal pit
ä»èªïŒfosse précaudale
è¡èªïŒchanfro pré-caudal
â 2. ã€ã¿ãã¶ã¡ã«ãããåé¡åŠçæçŸ©
äžå°Ÿå窩ã¯ãåãªãåã蟌ã¿ã§ã¯ãªããã€ã¿ãã¶ã¡ïŒGaleocerdo cuvierïŒãä»ã®ãµã¡ãšèå¥ããããã®èšºæåœ¢è³ªïŒåé¡åŠçããŒïŒã®äžã€ã§ããã
âŒCompagno "Sharks of the World" / FAO çš®èå¥ã·ãŒã
Galeocerdo å±ã®å®çŸ©çç¹åŸŽãšããŠä»¥äžãæèšïŒ
"low but prominent dermal keels present on caudal peduncle; upper precaudal pit transverse and crescentic"
ïŒå°Ÿæéšã«äœããæçãªç®èæ§ã®éèµ·ç·ãååšïŒäžå°Ÿåçª©ã¯æšªåãã§äžæ¥æåœ¢ïŒ
åºå
žïŒ
sharks.linnaeus.naturalis.nlâŠ
âŒæ¥æ¬èªæç®ã«ãããèšèŒ
(1) Wikipedia æ¥æ¬èªçãã€ã¿ãã¶ã¡ã
ãèé°ééèµ·ç·ãå°Ÿæéšéèµ·ç·ãååšãããã
åºå
žïŒ
ja.wikipedia.org/wiki/ã€ã¿ãã¶ã¡
(2) æ±äº¬éœå³¶ããèŸ²ææ°Žç£ç·åã»ã³ã¿ãŒãã€ã¿ãã¶ã¡ã
ãå°Ÿæã«ã¯éèµ·ç·ããããâŠã¡ãžãã¶ã¡ç§ã®ãµã¡ã®äžã§ãå°Ÿæéšã«éèµ·ç·ãããçš®ã¯ãšã·ããªã¶ã¡ Prionace glauca ãšã€ã¿ãã¶ã¡ã®2çš®ã§ãããã
åºå
žïŒ
ifarc.metro.tokyo.lg.jp/archâŠ
(3) åºå³¶å€§åŠããžã¿ã«ãã¥ãŒãžã¢ã ãã€ã¿ãã¶ã¡ã
ãå»ã¯åããå°Ÿæéšã«çºéããéèµ·ç·ãæã€ããšã§ä»çš®ãšåºå¥ããããã
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žïŒ
digital-museum.hiroshima-u.aâŠã€ã¿ãã¶ã¡
ãããéèµ·ç·ïŒdermal keelïŒãšäžå°Ÿå窩ïŒprecaudal pitïŒã¯åãå°Ÿæéšã«å¯Ÿã«ãªã£ãŠååšããGaleocerdo å±ã®èšºæã»ããã圢æããã
â 3. æ©èœçæçŸ©
precaudal pit ã®çç©åŠçæ©èœã¯ä»¥äžã®éãïŒ
ã»å°Ÿãã¬ãéæ³³æã«æè»ã«ããªãããã®å±æ²ç¹ïŒãã³ãžæ§é ïŒ
ã»å°Ÿæéšã®éèµ·ç·ïŒkeelïŒãšå¯Ÿããªããå°Ÿãã¬ã®æ¯ãã«ããæšé²å¹çãé«ãã
ã»å°Ÿéšã®äžäžéåã®æ¯ç¹ãšããŠæ©èœãã
âŒã«ããæ°Žç£æµ·æŽç / Shark Anatomy ã®è§£èª¬
"The tail region itself consists of the caudal peduncle and the caudal fin. The caudal peduncle may have notches known as precaudal pits found just ahead of the caudal fin."
ïŒå°Ÿéšã¯å°Ÿæéšãšå°Ÿãã¬ãããªããå°Ÿæéšã«ã¯å°Ÿãã¬ã®ããåã« precaudal pit ãšåŒã°ããåã蟌ã¿ãããå ŽåãããïŒ
åºå
žïŒ
dfo-mpo.gc.ca/species-especeâŠ
â 4. åžå Žæµéåäœã§ç¹ã«ç®ç«ã€çç±
åžå Žã«äžŠã¶ã€ã¿ãã¶ã¡ã®åäœã§ã¯ããã®åã蟌ã¿ããã¹ãªããç¶ã®ã©ã€ã³ããšããŠåŒ·èª¿ãããŠèŠããããšãããã
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ç®èãšçèã匷ãç·åŒµããŠãããããprecaudal pit ã¯æµ
ãå¹ã¿ãšããŠããèŠãããå€èгäžã¯ã»ãšãã©ç®ç«ããªãã
âŒæ»åŸã»æ°ŽæãåŸã»åžå Žé³åæã®åäœ
çèãåŒç·©ããçµåçµç¹ã®åŒµãã倱ãããããã«æ°ŽåãæããŠãããããæ¬æ¥ã®å¹ã¿ïŒpitïŒãæ·±ãéããŠãã¹ãªããç¶ã®å²ãç®ããšããŠé¡åšåããã
ãããã£ãŠãåžå Žã®ã€ã¿ãã¶ã¡ã«ã¯ãã®åãç®ãç¹æã«ãããã®ã§ã¯ãªããåžå Žã§èŠãããããç®ç«ã£ãŠèŠããã ãã§ãããæ¬è³ªçã«ã¯ãã¹ãŠã®åäœã«çãŸãã€ãåãã£ãŠããæ§é ã§ããã
â 5. åŠå®ããã仮説ïŒèª¿æ»ã«ããé€å€ãããå¯èœæ§ïŒ
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Ãåžå Žã§ã®è¡æãã»ç¥çµç· ãã«ããåŠççã§ã¯ãªã
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ã§ã®è骚åæïŒå°ŸåãïŒãè³ç· ããªã©ãäžè¬çã ããå°Ÿæéšäžé¢ã«æšªåãã¹ãªãããå
¥ããåŠçæ³ã¯æ¥æ¬ããã³åœå€ã®æç®ãåºã調æ»ããŠã確èªãããªãã
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âFAO çš®èå¥ã·ãŒãããã³ Compagno ã® "Sharks of the World" ã«ãããŠãæç¢ºã«è§£ååŠçæ§é ãšããŠèšèŒãããŠããã
â 6. ãŸãšãäžèЧ
ã»æ£äœïŒäžå°Ÿå窩ïŒupper precaudal pitïŒ
ã»æ§è³ªïŒã€ã¿ãã¶ã¡ã®æ£åžžãªè§£ååŠçæ§é ïŒå·ã§ãåŠççã§ããªãïŒ
ã»å ŽæïŒå°Ÿãã¬ä»ãæ ¹ã®çŽåãå°Ÿæéšã®äžé¢
ã»åœ¢ç¶ïŒæšªåãã»äžæ¥æåœ¢ïŒtransverse and crescenticïŒ
ã»çš®ãšããŠã®æå³ïŒã€ã¿ãã¶ã¡å± Galeocerdo ã®åé¡åŠç蚺æåœ¢è³ªã®äžã€
ã»æ©èœïŒå°Ÿãã¬ã®æè»ãªããªããå¯èœã«ãããã³ãžæ§é ïŒéèµ·ç·ãšå¯Ÿããªãéæ³³å¹çã«å¯äž
ã»ãªãåžå Žåäœã§ç®ç«ã€ãïŒçåã¯ç®èãšçã®ç·åŒµã§èŠãã«ããããæ»åŸåŒç·©ãšè±æ°Žã§æºãéããŠé¡åšåãã
ã»ä»ã«åãæ§é ãæã€ãµã¡ïŒãšã·ããªã¶ã¡ïŒPrionace glaucaïŒãªã©ãã¡ãžãã¶ã¡ç®ã®å€ãã®çš®
â 7. åç
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âŒåœéæç®ã»åŠè¡ããŒã¿ããŒã¹
ã»Compagno, L.J.V. "Sharks of the World: Genus Galeocerdo"ïŒNaturalis Biodiversity CenterïŒ
ã
sharks.linnaeus.naturalis.nlâŠ
ã»FAO Species Identification Sheets â Sharks
ã
fao.org/4/w7192e/w7192e39.pdâŠ
ã
fao.org/4/ad468e/ad468eOO.pdâŠ
ã»FishBase â Glossary: precaudal pit
ã
fishbase.se/glossary/GlossarâŠ
ã»FishBase â Galeocerdo cuvier
ã
fishbase.org/summary/GaleoceâŠ
ã»Shark-References â Galeocerdo cuvier
ã
shark-references.com/speciesâŠ
ã»Wikipedia (English) â Tiger shark
ã
en.wikipedia.org/wiki/Tiger_âŠ
ã»Department of Fisheries and Oceans Canada â Shark Anatomy
ã
dfo-mpo.gc.ca/species-especeâŠ
ã»The Campana Lab, University of Iceland â Shark Anatomy: Fins
ã
uni.hi.is/scampana/sharks/shâŠ
ã»Fishes of Texas â Galeocerdo cuvier
ã
fishesoftexas.org/taxa/galeoâŠ
ã»Shark Research Institute â Tiger Shark
ã
sharks.org/tiger-shark-galeoâŠ
ã»
SharksAndRays.com â Tiger Shark
ã
sharksandrays.com/tiger-sharâŠ
âŒæ¥æ¬èªæç®
ã»WikipediaïŒæ¥æ¬èªçïŒãã€ã¿ãã¶ã¡ã
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digital-museum.hiroshima-u.aâŠã€ã¿ãã¶ã¡
ã»WEBéå³éãã€ã¿ãã¶ã¡ã
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zukan.com/fish/internal1063
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natgeo.nikkeibp.co.jp/nng/arâŠ
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churaumi.okinawa/fishbook/00âŠ
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