Genetic characterization and description of Leishmania (Leishmania) ellisi sp. nov.: a new human-infecting species from the USA Author Sapp, Sarah G. H. Division of Parasitic Diseases and Malaria, Centers Author LoW, Ross Division of Parasitic Diseases and Malaria, Centers & Oak Ridge Institute of Science and Education, Oak Ridge, Author Nine, Gabriela Division of Parasitic Diseases and Malaria, Centers & Association of Public Health Laboratories, Silver Spring, Author Nascimento, Fernanda S. Division of Parasitic Diseases and Malaria, Centers Author Qvarnstrom, Yvonne Division of Parasitic Diseases and Malaria, Centers Author Barratt, Joel L. N. Division of Parasitic Diseases and Malaria, Centers text Parasitology Research 2024 52 2023-12-15 123 1 52 52 http://dx.doi.org/10.1007/s00436-023-08034-8 journal article 298995 10.1007/s00436-023-08034-8 20d996e5-dc7a-4257-b35d-77fa06ba2470 1432-1955 PMC10724317 38099974 11376887 A1470805-06FE-4AFA-B1F4-52BF8285894E Leishmania ( Leishmania ) ellisi sp. nov. Barratt, Sapp, and Qvarnstrom 2023 Synonyms: Leishmania sp. strain 218-L139, Leishmania sp. strain Arizona . Taxonomy: Phylum Euglenozoa (Cavalier-Smith, 1981) emend. (Cavalier-Smith, 2016) ; class Kinetoplastea (Honigberg, 1963) emend. (Vickerman, 1976) ; subclass Metakinetoplastina (Vickerman, 2004) ; order Trypanosomatida (Kent, 1880) ; family Trypanosomatidae (Doflein, 1901) ; subfamily Leishmaniinae (Maslov and Lukes 2012) emend. (Shaw, Camargo and Teixeira 2016) ; genus Leishmania (Ross, 1903) ; subgenus Leishmania (Shaw, Camargo and Teixeira, 2016) ; species Leishmania ( Leishmania ) ellisi (Sapp, Qvarnstrom, Barratt, 2023) . Type host: Humans, Homo sapiens . Vector is currently unknown. Type locality: Arizona , USA . Type material: Hapanotype , cryopreserved promastigotes stored in liquid nitrogen and original touch impression slide archived at the Centers for Disease Control and Prevention , USA . Strain designation: MHOM / US /2018/L139. Morphology: Cultured promastigotes are an average of 10.1 ± 2.2 µm in length (including the flagellum), ranging between 6.1 and 13.4 µm in length. Amastigotes in fixed and stained touch preparations are an average of 2.7 ± 0.26 µm on the longest axis, with a range of 2.7 to 3.2 µm. In Giemsa-stained preparations made from cultures, promastigotes are an average of 9.6 ± 3.4 µm in length (flagellum included), with a range of 5.7 to 15.4 µm. Etymology: Leishmania ( Leishmania ) ellisi is named in honor of parasitologist and Emeritus Professor J. T . Ellis, whose career in parasitology began with a PhD dissertation on the molecular phylogeny of Leishmania species. Diagnosis: Leishmania ( Leishmania ) ellisi is most closely related to Leishmania ( Leishmania ) mexicana and Leishmania ( Leishmania ) amazonensis . In Giemsa-stained preparations, its amastigotes are typical to those of other Leishmania species , and its promastigotes are typical in appearance compared to other Leishmania ( Leishmania ) species. Leishmania ( Leishmania ) ellisi possesses unique sequences at its 18S rRNA, 28S rRNA, Casein Kinase II α chain, Glyceraldehyde 3-phosphate dehydrogenase, and the RNA polymerase II largest subunit genes, and has a unique maxicircle sequence; sequences for these loci are publicly available under GenBank accession numbers OR689570, OR689569, OR695082, OR695080, OR695081, and OR701861, respectively.