Systematic review of the genera Rhabdostyla Kent 1880 and Orborhabdostyla Foissner et al. 2010 (Ciliophora, Peritrichia, Epistylididae) Author Souza, Pedro Mendes De ¹ Laboratório de Protozoologia, Programa de Pós-Graduação em Biodiversidade e Conservação da Natureza, Universidade Federal de Juiz de Fora, Martelos, 36036 - 900, Juiz de Fora, Brazil Author Rossi, Mariana Fonseca ¹ Laboratório de Protozoologia, Programa de Pós-Graduação em Biodiversidade e Conservação da Natureza, Universidade Federal de Juiz de Fora, Martelos, 36036 - 900, Juiz de Fora, Brazil Author Dias, Roberto Júnio Pedroso ¹ Laboratório de Protozoologia, Programa de Pós-Graduação em Biodiversidade e Conservação da Natureza, Universidade Federal de Juiz de Fora, Martelos, 36036 - 900, Juiz de Fora, Brazil text Zootaxa 2024 2024-01-12 5399 3 201 230 http://dx.doi.org/10.11646/zootaxa.5399.3.1 journal article 10.11646/zootaxa.5399.3.1 1175-5326 10516774 2134D857-542C-40A6-9557-CB8E042E4271 Rhabdostyla dixae ( Nenninger 1948 ) — Fig. 2 , N Epistylis ( Rhabdostyla ) dixae Stiller, 1933 — Stiller, 1971: 65 , pl. 35, fig. I Diagnosis: Size about 48.8–55 µm. Jar-like body, strongly protruding in the frontal third. Small stalk, about 10–11 µm to a third of the body size, quite thin. Peristomial collar with two-thirds of the body width, simple, collar-like, notched. Peristomial disc wide and arched, with a pronounced annular groove at the base. Infundibulum reaching about a third of the body’s length, which widens to a spherical shape in the lower portion. Contractile vacuole positioned at the lower left end of the infundibulum. Pellicle streaked at regular intervals. The basal part of the body with two lobes, one lobe slightly longer than the other. Macronucleus tape-shaped with folds at the ends, positioned transversely in the anterior part of the body, covering the lower end of the infundibulum, or obliquely reaching the peristomial disc. Found in freshwater environments on insect larvae of the species Dixa nigra . Remarks: diagnosis compiled from Nenninger (1948) and Stiller (1971) . According to Nenninger (1948) , the contraction creates a narrow, notched collar and the pellicle striations become more apparent.