Trachelophyllum brachypharynx Levander, 1894

"Trachelophyllids prefer terrestrial and semiterrestrial habitats (Kahl 1930; Foissner 1984, 1994, 2005; Foissner et al. 2002), but some have also been found in freshwater (Foissner et al. 1995, 1999) and one species, Trachelophyllum brachypharynx Levander, 1894, was reported from saltwater (e.g., Levander 1894, 1901; Coats and Clamp 2009; Telesh et al. 2009)". I found a population of this species in brackish water from the estuarine pond Pussy's Pond, an offshoot of Accabonac Harbor in the Town of East Hampton, New York. Except for its somewhat smaller size, my observation conforms perfectly to the description of Jang et. al. Size is often variable intraspecies. The lepidosomes forming a mucilagenous cortical surface layer are notoriously difficult to visualize in vivo but you can clearly see the roughened character of the cortex in my photos.

"Size about 380 × 40 μm in vivo, slightly contractile. Shape very narrowly fusiform, with a slightly to distinctly narrowed neck, gradually merging into a broadened trunk. Two ellipsoidal macronuclear nodules usually connected by a fine strand, with two to three broadly ellipsoidal micronuclei close to or attached to macronuclear nodules. Contractile vacuole terminal and comparatively small. Extrusomes filiform, slightly curved and with pointed ends, 30 µm long in vivo. On average, 24 ciliary rows, two anteriorly differentiated into an isostichad dikinetidal dorsal brush: row 1 composed of 40 dikinetids on average, row 2 of 33 dikinetids on average. Lepidosomes hat-shaped and about 4 × 3.7 µm in vivo". "Oral bulge rather conspicuous because distinctly set off from body proper; pin-shaped in extended specimens, while conical in contracted cells; not covered by lepidosomes".

Another marine Trachelophyllum species is Trachelophyllum apiculatum (Perty, 1852) Claparède & Lachmann, 1859. However this species is more flask shaped and has four macronuclear nodules.

Morphology, Ciliary Pattern and Molecular Phylogeny of Trachelophyllum brachypharynx Levander, 1894 (Litostomatea, Haptoria, Spathidiida) Seok Won JANG, Peter Vďačný, Shahed Uddin Ahmed Shazib and Mann Kyoon Shin. Acta Protozool. (2015) 54: 123–135

https://www.researchgate.net/publication/280571553_Morphology_Ciliary_Pattern_and_Molecular_Phylogeny_of_Trachelophyllum_Brachypharynx_Levander_1894_Litostomatea_Haptoria_Spathidiida

you enter the bathroom, expecting nothing unusual, but unknowingly, your bumhole is met with a pair of soulless eyes staring back at it.

as you start to sit down, you hear something slosh in the water beneath you.

you jump up, startled.

as you peer into the toilet bowl, you see him, the prince of wadda mooli himself.

you pay your respects and escort him outdoors–back to his kingdom

you then reclaim your porcelain throne

Collotheca species, possibly C. ornata, attached to the Elodea from fresh water Town Pond. Collotheca belongs to the rotifer class Monogononta, rotifers with only one ovary. These rotifers are sessile; they are either attached to each other forming a spherical colony, or attached individually to the substrate. Each rotifer secretes a gelatinous tube into which it withdraws when disturbed. Phase contrast Zeiss Photomicroscope III using Neofluar PH2 160.40 with Optovar set at x1.6 plus variable phone cropping. At one point, a little Menoidium decided to tempt fate and tease the rotifer by poking its infundibulum.

The absence of setae inserting between the lobes points to Collotheca ornata (thanks @shanesmicroscope ) in contrast to the similar species C. coronetta which has setae on the surfaces between the lobes (see illustration from Shiel and Plewka below).
https://www.plingfactory.de/Science/Atlas/KennkartenTiere/Rotifers/01RotEng/source/Collotheca%20ornata%20cornuta.html

Collotheca Harring, 1913
Class Rotatoria: Order Paedotrochida: Family Collothecidae
Synonym Floscularia Ehrenberg, 1832

Corona very large, circular, lobed, or pointed. The margins of the corona are furnished with long, very fine setae. Setae not arranged in whorls. The digestive system is very characteristic. The mastax has incudate trophi. Mostly sessile forms, the Collothecans are usually found in clear, gelatinous tubes. In a clear gelatinous tube. Foot terminated by a long, nonretractile peduncle, ending in an adhesive disc. Mostly sessile. Five species are free-swimming and may be found in lake plankton.