Rhabdostyla vernalis Stokes 1887

Souza, Pedro Mendes De, Rossi, Mariana Fonseca & Dias, Roberto Júnio Pedroso, 2024, Systematic review of the genera Rhabdostyla Kent 1880 and Orborhabdostyla Foissner et al. 2010 (Ciliophora, Peritrichia, Epistylididae), Zootaxa 5399 (3), pp. 201-230 : 223

Rhabdostyla vernalis Stokes 1887

— Fig. 4 , Q’

[ Rhabdostyla] (Rhabdostyla) vernalis Stokes, 1887 — Kahl, 1935: 676, pl. 129, fig. 13

Epistylis (Rhabdostyla) vernalis Stokes, 1887 — Stiller, 1971: 69, pl. 36, fig. A

Diagnosis: Size about 48–50µm long and 20µm wide. Urceolate body, often gibbous, and elongated, twice as long as wide. Peduncle is short, measuring 8–10µm to one-eighth the length of the body. Finely and transversely striated pellicle. Elevated and convex peristomial disc, occasionally developing a central and conspicuous nipplelike projection. With two ciliary circles. Peristomial collar slightly slanted, not revolved. Infundibulum, extends to the middle of the body, prominent vestibular cilia. Contractile vacuole located in the anterior half of the body. Macronucleus hand-like shaped, curved, located in the posterior part of the body. Granular cytoplasm. Found on microcrustaceans of the genera of Cypris and Cyclops .

Remarks: diagnosis compiled from Stokes (1887), Kahl (1935) and Stiller (1971). According to Stokes (1887), when contracted, it assumes an oval shape, often waving and the peduncle invaginates in the posterior region of the body.

Figures

FIGURE 4. Schematic drawing of representatives of the Rhabdostyla genus. F’: Rhabdostyla porculus: G’: Rhabdostyla pristinis; H’: Rhabdostyla ringens; I’: Rhabdostyla similis; J’: Rhabdostyla scyphidiformis; K’: Rhabdostyla scyphoides; L’: Rhabdostyla sessilis; M’: Rhabdostyla spheroides; N’: Rhabdostyla taboadai; O’: Rhabdostyla tritora; P’: Rhabdostyla tubificis; Q’: Rhabdostyla vernalis.