Los Iintlanzi zemela, ekwabizwa ngokuba yi-Apteronotus Leptorhynchus, ziintlobo zeentsapho ze Apteronotidae, kwaye ezizalelwa emilanjeni nasemachibini kwilizwekazi lase Mzantsi Melika. Nangona igama labo liyintlanzi yommese, abaninzi bayabazi njengomoya omnyama, kwaye baye banemfashini iminyaka ethile, ke kuya kuba lula kakhulu ukuyifumana kwiivenkile ezizodwa zezilwanyana.
Ezi zilwanyana zibonakaliswa ngokuba nomzimba omnyama onemigca emhlophe ekupheleni kwemizimba yazo, kodwa yindlela ezimile ngayo ezenza ezi ntlanzi zithandeke kakhulu. Ngendlela efanayo, luxolo nangona luza kuba lukhulu irhamncwa tetras amancinci.
Kubalulekile ukuba uqaphele ukuba ezi zilwanyana zinokulinganisa ukuya kuthi ga kwiisentimitha ezingama-50 ubude, iyenze ukuba ibe yintlanzi engakulungelanga kwaphela ukuba ne-aquarium yasekhaya, ngaphandle kokuba unedama elikhulu ngokwaneleyo ukuba lingagcinwa apho, nangona ndincoma ukuba andinayo ekhayeni kodwa endaweni yezixhobo zomboniso nakwi zoo. Ngendlela efanayo, ezi zilwanyana azihlali kakhulu, ke kuyacetyiswa ukuba kugcinwe uhlobo olunye lwentlobo ukuthintela iingxaki zomhlaba.
I-aquarium efanelekileyo yezi zilwanyana iya kuba malunga ne-30 yeelitha zamanzi, xa zisencinci, ngelixa zikhulile, siza kufuna enye yeelitha ezingama-55. Ungalibali ukuba ezi ntlanzi ziyatya izibungu zezinambuzane, kunye nee-crustaceans ezincinci, ukutya okomileyo kunye neentshulube ezincinci.