Cestode tapeworms of the genus Spirometra belong to the family Diphyllobothriidae which infect amphibians, birds and mammals. The adult stage of Spirometra spp. parasitize the intestine of carnivores, felids and canids including domestic dogs and cats. Spargana are plerocercoid larvae of cestode tapeworms of the genus Spirometra, which are found in paratenic hosts of Spirometra spp. such as amphibians, reptiles and mammals including humans.Spirometrid tapeworms previously reported in African mammals were described by Baer (1924) [1]. S. pretoriensis was assigned the name Lühella pretoriense (Baer, 1924) and became synonymous with Diphyllobothrium pretoriense by Baer (1926), which was found in bat-eared fox (Otocyon megalotis) from South Africa (Baer, 1926) and later in African wild dog (Lycaon pictus) from Congo (Baer and Fain, 1955) [2]. S. theileri has been found in bush cat (Leptailurus serval), tiger cat (Felis lybica) near Pretoria, and lion from Congo (Baer, 1959) [3]. According to some studies, Spirometra and Taenia species were the most prevalent parasites in African lion, spotted hyena and African wild dog [4][5][6][7][8]. The spotted hyenas in Kenya and Zambia were reported to have a high rate of Spirometra infection with 74.3% and 22% in the feces of examined animals, respectively [5]. Some lions in Tanzania and Zambia were noted as having 63% and 87% infection of spirometrid tapeworms, respectively [5,6]. Spirometra species were the most commonly found in lion and second most common parasite in hyenas. The Spirometra species in lions is S. theileri whereas the species found in hyenas is generally accepted to be S. pretoriensis, although both ISSN (Print) Abstract: In the present study, a Spirometra species of Tanzania origin obtained from an African leopard (Panthera pardus) and spotted hyena (Crocuta crocuta) was identified based on molecular analysis of cytochrome c oxidase I (cox1) and NADH dehydrogenase subunit I (nad1) as well as by morphological observations of an adult tapeworm. One strobila and several segments of a Spirometra species were obtained from the intestine of an African male leopard (Panthera pardus) and spotted hyena (Crocuta crocuta) in the Maswa Game Reserve of Tanzania. The morphological characteristics of S. theileri observed comprised 3 uterine loops on one side and 4 on the other side of the mid-line, a uterine pore situated posterior to the vagina and alternating irregularly either to the right or left of the latter, and vesicular seminis that were much smaller than other Spirometra species. Sequence differences in the cox1 and nad1 genes between S. theileri (Tanzania origin) and S. erinaceieuropaei were 10.1% (cox1) and 12.0% (nad1), while those of S. decipiens and S. ranarum were 9.6%, 9.8% (cox1) and 13.0%, 12.6% (nad1), respectively. The morphological features of the Tanzania-origin Spirometra specimens coincided with those of S. theileri, and the molecular data was also consistent with that of S. theileri, thereby demonstrating the distribution of S. theileri in Tanz...