Here we report a novel Taenia species, provisionally named as “Taenia sp. Eurasian lynx”, from the Eurasian lynx. Some common herbivorous prey items of this wild felid, such as the common hare (Lepus capensis) and the ibex (Capra ibex) are the most likely candidates to act as intermediate hosts of this novel species, which should be investigated further. In addition, another tapeworm species, T. laticollis was found in Eurasian lynx for the first time in China.
“Taenia sp. Eurasian lynx”, is phylogenetically closely related to T. hydatigena, and together these form a sister clade to T. regis reported from lion (Panthera leo) in Kenya and T. lynciscapreoli from the grey wolf, Eurasian lynx in Russia, Finland and Poland [4, 5, 13-15]. Analysis of the COX1 protein amino acid sequences showed that in comparison with T. hydatigena, T. regis and T. lynciscapreoli, “Taenia sp. Eurasian lynx” has 2-4 amino acids substitutions (Supplementary Fig. 2). These findings confirm “Taenia sp. Eurasian lynx” as a novel Taenia species, which is also supported by the morphological characteristics of the scolex and rostellar hooks showing differences from those of other Taenia spp. that are known to infect lynxes [4, 15].
As reported previously, the definitive hosts of T. laticollis include the Eurasian lynx, the Canada lynx (Lynx canadensis), the timber wolf (Canis lupus lycaon) and the coyote (Canis latrans) [16-19]. Here T. laticollis haplotype C was also found in Eurasian lynx in China. This finding suggests that the host specificity of T. laticollis in lynxes and wolves should be evaluated further according to haplotypes.
The definitive hosts of T. hydatigena, the species closest related to “Taenia sp. Eurasian lynx”, include the coyote (Canis latrans), the timber wolf (Canis lupus lycaon), the black-backed jackal (Lupulellamesomelas), the Eurasian lynx (Lynx lynx), the Canada lynx (Lynx canadensis), the brown bear (Ursus arctos), whereas its intermediate hosts are the black-tailed jack rabbit (Lepus californicus), the European ground squirrel (Spermophilus citellus), domesticated ruminants, the springbok (Antidorcas marsupialis), the black wildebeest (Connochaetus gnou), the impala (Aepyceros melampus), the hartebeest (Alcelaphus buselaphus), the blue wildebeest (Connochaetus taurinus), the blesbuck (Damaliscus pygargus phillipsi) and the tsessebe (Damaliscus lunatus) [5, 7, 13, 17, 18, 20-22]. The West Junggar Mountains, between the Tianshan and Altai mountain belts, are located on the western rim of the Junggar Basin in northwestern China. Their landscape can be characterized as discontinuous treeless hills, with an altitude range from 2000-3000 m above sea level. In this region, the wildlife fauna relevant to the life cycles of cyclophyllidean cestodes of the family Taeniidae include the Pallas’s cat (Otocolobus manul), the Eurasian lynx (Lynx lynx), the snow leopard (Panthera uncia), the grey wolf (Canis lupus), the red fox (Vulpes vulpes), the corsac fox (Vulpes corsac) and the Cape hare (Lepus capensis), all of which are sporadically distributed . Since the number of Eurasian lynxes is limited in the West Junggar Mountains, other felids, as well as canids and lagomorphs should be investigated to systematically explore the definitive and intermediate hosts of T. laticollis and “Taenia sp. Eurasian lynx” in the near future.