C
GUATEMALACITY（Reuters）–Afishthatlivesinmangroveswamps（红树沼泽）acrosstheAmericascanliveoutofwaterformonthsatatime,similartohowanimalsadapted（适应）tolandmillionsofyearsago,anewstudyshows.
TheMagroveRivulus,atypeofsmallkillifish,livesinsmallpoolsofwaterinacertaintypeofemptynutorevenoldbeercansinthemangroveswampsofBelize,theUnitedStatesandBrazil.Whentheirlivingplacedriesup,theyliveonthelandinlogs（圆木），saidScottTaylor,aresearcherattheBrevardEndangeredLandsPrograminFlorida.
Thefish,whosescientificnameisRivulusmarmoratus,cangrowaslargeasthreeinches.Theygrouptogetherinlogsandbreatheairthroughtheirskinuntiltheycanfindwateragain.
Thenewscientificdiscoverycameafteratr iptoBelize.
“Wekickedoveralogandthefishjustcamecrowdingout,”TaylortoldReutersinneighboringGuatgemalabytelephone.HesaidhewillmakehisstudyonthefishknowntothepublicinanAmericanmagazineearlynextyear.
Inlabtests,Taylorsaidhefoundthefishcanliveupto66daysoutofwaterwithouteating.
Someotherfishcanliveoutofwaterforashortperiodoftime.ThewalkingcatfishfoundinSoutheastAsiacanstayonlandforhoursattime,whilelungfishfoundinAustr alia,AfricaandSouthAmericacanliveoutofwater,butonlyinaninactivestate.ButnootherknownfishcanbeoutofwateraslongastheMangroveRivulusandremainactive,accordingtoPatr iciaWright,abiologistatCanada’sUniversityofGuelph.
Furtherstudiesofthefishmaytellhowanimalschangedovertime.
“Theseanimalsliveinconditionssimilartothosethatexistedmillionsofyearsago,whenanimalsbeganmakingthetr ansition（过渡）fromwaterontoland,”Wrightsaid.
49.TheMangroveRivulusisatypeoffishthat_______.
A.likeseatingnuts
B.preferslivingindryplaces
C.isthelongestlivingfishonearth
D.canstayalivefortwomonthsoutofwater
正确答案：D
