The expanding phylogenetic tree of trypanosomatid flagellates (Kinetoplastea: Trypanosomatidae) contains a long-known and phylogenetically well-supported species-rich lineage that was provisionally named as the 'jaculum' clade. Its members were found in representatives of several unrelated families of heteropteran bugs captured in South and Central America, Europe, Africa, and Asia. However, this group resisted introduction into the culture, a needed prerequisite for its proper characterization. Here we describe four new cultivable species, which parasitize various parts of their hosts' intestine, including the thoracic and abdominal part of the midgut, hindgut, and Malpighian tubules. Morphologically, the cultured flagellates vary from relatively short stumpy promastigotes to long slender leptomonad cells. Some species form straphangers (cyst-like amastigotes) both in vivo and in vitro, initially attached to the basal part of the flagellum of the mother cell, from which they subsequently detach. To formally classify this enigmatic monophyletic cosmopolitan clade, we erected Obscuromonas gen. nov., including five species: O. modryi sp. nov. (isolated from the true bug host species Riptortus linearis captured in the Philippines), O. volfi sp. nov. (from Catorhintha selector, Curaçao), O. eliasi sp. nov. (from Graptostethus servus, Papua New Guinea), O. oborniki sp. nov. (from Aspilocoryphus unimaculatus, Madagascar), and O. jaculum comb. nov. (from Nepa cinerea, France). Obscuromonas along with the genus Blastocrithidia belongs to the newly established Blastocrithidiinae subfam. nov.

Faculty of Science University of Ostrava Ostrava Czech Republic; Martsinovsky Institute of Medical Parasitology Sechenov University Moscow Russia

Institute of Parasitology Biology Centre Czech Academy of Sciences České Budějovice Czech Republic

Institute of Parasitology Biology Centre Czech Academy of Sciences České Budějovice Czech Republic; Faculty of Science Charles University Prague Czech Republic

References provided by Crossref.org

Identification of diverse RNA viruses in Obscuromonas flagellates (Euglenozoa: Trypanosomatidae: Blastocrithidiinae)

Blastocrithidia nonstop mitochondrial genome and its expression are remarkably insulated from nuclear codon reassignment

In silico prediction of the metabolism of Blastocrithidia nonstop, a trypanosomatid with non-canonical genetic code

Shining the spotlight on the neglected: new high-quality genome assemblies as a gateway to understanding the evolution of Trypanosomatidae

Comparative Analysis of Three Trypanosomatid Catalases of Different Origin

Euglenozoa: taxonomy, diversity and ecology, symbioses and viruses