An isopod specimen from the stomach of a zoachid fish collected from the sea off Iwase, Toyama

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An isopod specimen from the stomach of a

zoachid fish collected from the sea off Iwase, Toyama

journal or

publication title

Bulletin of the Toyama Science Museum

number 15

page range 31‑33

year 1992‑03‑20

URL http://repo.tsm.toyama.toyama.jp/?action=repos itory̲uri&item̲id=608

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BulletinoftheToyamaScienceMuseumNo･'5,pp､31‑33（1992：

AnlsopodSpecimenfromthestomachofaZoachidfishcollected fromtheSeaoffIwase，Toyama＊

富山市沖のアゴゲンゲの胃中から発見されたウミミズムシ類（等脚目甲殻類）の1標本

布村昇

富山市科学文化センター

富山市科学文化センターの宮本望専門員が富山市岩瀬沖のアゴゲンゲの消化管から奇妙

な形態の等脚類を発見した。筆者の研究によるとこれはウミミズムシ科Janiridaeに属するものであり、ノtz"j花叱属に近いと思われるが、自由腹節が2個あるなど、特異な形態を持っている。

しかし、本標本は魚の消化管中から発見されたものであり、胸部附属肢を全て欠いている不完全標本であるため、正確な種および属の決定は出来なかった。

Duringthesurveyofdeepseashells，Mr､MiyamotooftheToyamaScienceMuseum happenedtofindaqueer‑lookingisopodcrustaceanfromthestomachofazoachidfish

庇/γOSC〃"z〃＃加yα加膨"sjS・Thespecimenwashandedovertomeformystudy、Oncloser

examinationsofmine，itprovedtorepresentaspeciesbelongingtothefamilyJaniridae whichmaybelongtothegenus〃?" 伽．

Beforegoingfurther，IwishtoexDressmvthankstoMr，NozomuMivamotoforhis kindnessingivingmeaninterestingspeclmen．

Janiridaesp・

Fig．1

Mz舵γねノ α加加：13(7.2mminbodylength)，fromthestomachofzoachidfish・

凡ｵmscﾙ加趣j 加yα加 "s応．ThespecimenisdepositedattheTovamaScienceMuseum

(TOYACr‑lll75)．

Dgscγゆ"0":Body2．6timesaslongaswide・Colorwhiteinalcohol・Cephalonrectangu‐

larwithamedialprojectiononanteriormargin、Allthepartsofsurfacesmooth

Eyessmall,numberofommatidianotdiscemed・CephalontoDeraeonalsomiteVwithlto

3pairsofacuteprocesses，ButtheperaeonalsomitesVI‑VIIandpleotelsonsmooth・Two

freepleonalsegments、Pleotelsontrlangular(Fig.H)．

Antennula(Fig.B)with3peduncularsegmentsand22flagellarsegments．

＊Contl･ibutionfromtheTovamaSciecneMuseumNo､115

Q 1 J 上

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NoboruNunomul●a

Antenna(Fig.C）broke､,onlybasal2segmentswereremained・

Mandible(FigC)；parsincisivacomposedof3teeth；laciniamobilissingle‑toothed；a groupofsetaebehindlaciniamobilis;processusmolarisisrepresentedbyarelativelvsmal:

process、

Maxillula(FigD)slenderwithl4teethatthetipofouterlobe

Maxilla(Fig.E);31obesofequallength,ilmerlobewidewithl5setae;middleandout管

lobesslender，eachwith3setae･

Maxilliped（Fi9.F);enditerectangularwithl2〜l3teethatthedistalend；2coupling hooksontheinnerborder，Palp5‑segmented;segmentlsmall;segments2and3broadwith

⁝且Ｉ三︲１１１１１１１

１ｍ

E

一一

獄ノ

Fig.1Janiridaesp

A・Dorsalview；B･Firstantenna;C・Mandible;D･OuterlobeofMaxillula;EMaxi:‐

la;F,Maxilliped.G,Malesecondpleopod;H,Pleotelson(All:SDecimenfI･omTovama Bav)．

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A〃iso加(！ z脚g〃増ﾉ〃β℃籾／"〔?s qヴ伽as2，九脚a

3，lOsetaeonlnnermargln，respectively，segment4slenderwithlOsetae；terminal segmentslender、

Alltheperaeopodsmissing，

Malesecondpleopod(Fig.G);exopod2‑segmented;firstsegmentlong;secondsegment rectangular;terminalsegment,withaswollenpartinthemiddlepart,taperstowardsthetipo R""α液s：Ifthepresentspeclmenbelongstothegenusノtr"かg/〃，itismostalliedto

〃""gﾉﾙz〃zz〃e fromtheAtlanticOcean,buttheformerisseparatedfromthelatterinthe followingfeatures:(1)shapeofpleonalsomites,(2)presenceofprotuberancesonpleotelson(3f shaDeofsecond，TheDresentspecimenisimperfect,therefore，Icouldnotexammeonlya

limitedpart，Irefrainedtoestablishanewspecles．

References

Kussakin,0．G．l988Mal‑ineandbrackishlsopodaofcoldandtemperatewatersofthe

NorthemHimispherelll,SuborderAsellota、AkademyofScienceU.S､S､R・Leningrad

l‑l70(inRussian)．

Menzies,RJ， α/、1962．TheisoDosofabvssaldeDthintheAtlanticOcean・Vema

Research,ser．：79‑206.

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