Spirometra sp. 2

Kuchta, Roman, Phillips, Anna J., Toma & Scholz, s, 2024, Diversity and biology of Spirometra tapeworms (Cestoda: Diphyllobothriidea), zoonotic parasites of wildlife: A review, International Journal for Parasitology: Parasites and Wildlife 24, pp. 100947-100947 : 100947-

Spirometra sp. 2 (American lineage) Fig. 4 .

Synonym: Spirometra decipiens complex 1 of Kuchta et al. (2021) and Vettorazzi et al. (2023).

Material examined: Only one immature piece (hologenophore) from Lynx rufus , USA (Illinois) ( IPCAS C-987 ) .

Definitive host (molecularly confirmed): Domestic cat Canis familiaris in Uruguay; crab-eating fox Cerdocyon thous in Brazil and Uruguay; domestic cat Felis catus in Brazil and Chile; lesser grison Galictis cuja (Molina) in Brazil; Geoffroy’ s cat Leopardus geoffroyi in Brazil; pampa cat Leopardus munoai (Xim´enez) in Uruguay); ocelot Leopardus pardalis in Argentina; pampas fox Lycalopex gymnocercus (Fischer) in Argentina; hoary fox Lycalopex vetulus (Lund) in Brazil; bobcat Lynx rufus in USA; puma Puma concolor in Argentina.

Intermediate (or paratenic) hosts (molecularly confirmed): Human Homo sapiens in Venezuela; Crotalus sp. in Brazil; Philodryas patagoniensis in Uruguay; Didelphis albiventris in Brazil, Uruguay; Austrolebias charrua in Uruguay.

Geographical distribution: South America ( Argentina, Brazil, Chile, Uruguay, Venezuela), North America ( USA – Illinois).

Representative DNA sequences: Miyadera et al. (2001), Petrigh et al. (2015), Almeida et al. (2016), Arrabal et al. (2020), Armúa-Fern´andez et al. (2021), Kuchta et al. (2021), Fredes et al. (2022), Kikuchi et al. (2021), Vettorazzi et al. (2023); Trindade et al. unpublished – see the Genbank database).

Selected morphological features: The uterus is similar in appearance to the Palaearctic species, i.e. it lacks the conspicuously enlarged C-shaped distal loops typical of S. decipiens ( Fig. 4 ).

Remarks

Kuchta et al. (2021) found two different lineages of Spirometra tapeworms in North and South America and named them S. decipiens complex 1 and S. decipiens complex 2. Tapeworms of complex 1 form a relatively well-supported lineage between the European S. erinaceieuropaei and the predominantly Palaearctic S. mansoni and S. asiana ( Fig. 1 ). This complex 1 consists of specimens of various South American carnivores (adults) and plerocercoids of reptiles and humans, including the enigmatic Sparganum proliferum ( Arrabal et al., 2020) . Vettorazzi et al. (2023) have also indicated the rivulid killifish Austrolebias charrua as paratenic host of this tapeworm, which is the first report of Spirometra plerocercoids in fish.

Figures

Fig. 4. Microphotographs of Spirometra spp. from North and South America. A–C – Scolex and gravid proglottids of S. decipiens syntype from Puma concolor, Brazil (NMW 2682, 2699). D, E – gravid proglottids of S. decipiens syntype from Herpailurus yagouaroundi (NMW 12781). F–J – Gravid proglottids and sagittal section of S. decipiens hologenophore from Chrysocyon brachyurus, Bolivia (USNM 1233899). K–O – Scolex and proglottids of S. mansonoides syntype from Felis catus, USA (USNM 1333923). P – Immature proglottid of Spirometra sp. 2 hologenophore from Lynx rufus, USA Illinois (IPCAS C-987).

Fig. 1. Phylogenetic tree of the interrelationships of the genus Spirometra based on selected cytochrome c oxidase subunit I (cox1) gene data (long sequences), maximum likelihood. The branch length scale bar indicates number of substitutions per site. Colours highlight specimens of different species; samples without colour represent undescribed species. See Supplementary Fig. 1 for more data based on larger dataset, but based on shorter sequences. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)