Evidence map›Paper›PMID 41720861›Full record

ArticleScientific reports2026

Stentor stipatus is a new unicellular species that demonstrates habituation and unique phototaxis.

Deepa H Rajan, Benjamin Lee, Ashley Albright, Eric Tang, Kristen Ressler, Arnie Maravillas, Carmen Vargas, Wallace F Marshall, Daniel B Cortes

Abstract read
In one paragraph

Article in Scientific reports, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Deepa H RajanUCSF Genentech Hall N376, 600 16th Street, San Francisco, CA, 94158, USA.
Benjamin LeeHensill Hall 534, 1600 Holloway Ave, San Francisco, CA, 94132, USA.
Ashley AlbrightUCSF Genentech Hall N376, 600 16th Street, San Francisco, CA, 94158, USA.
Eric TangUCSF Cardiovascular Research Institute, 555 Mission Bay Boulevard South, San Francisco, CA, 94158, USA.
Kristen ResslerSteger 162B, 1015 Life Science Circle, Blacksburg, VA, 24061, USA.
Arnie MaravillasHensill Hall 534, 1600 Holloway Ave, San Francisco, CA, 94132, USA.
Carmen VargasHensill Hall 534, 1600 Holloway Ave, San Francisco, CA, 94132, USA.
Wallace F MarshallUCSF Genentech Hall N376, 600 16th Street, San Francisco, CA, 94158, USA.
Daniel B CortesSteger 162B, 1015 Life Science Circle, Blacksburg, VA, 24061, USA. dbcortes@vt.edu.

Funding

Origins of Cell GeometryR35GM130327 · NIGMS · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · PI Wallace Marshall · 2019 to 2026
$5.3M
NIH HHS 5K12GM081266NIH HHS R35GM130327
6 · The paper itself

Abstract

Stentor, the genus of large trumpet-shaped ciliates, is well-known for its complex morphology and striking behaviors. Members of this genus are distributed throughout the world in a wide and diverse pool of freshwater ecosystems. Recently, the molecular phylogeny of Stentor has been explored through comparison of 18 S small subunit (SSU) ribosomal DNA (rDNA) sequences, clarifying several previously mischaracterized species and species complexes. However, despite their wide distribution, to-date, only about a dozen species of Stentor have been described and verified by phylogenetic means. Here, we introduce the discovery of a new species within genus Stentor: Stentor stipatus spec. nov., so named for their distinctive cytosolic dark pigmented granules which surround the macronucleus and are also present cortically alongside cortically-distributed green microalgae. We present morphological, phylogenetic, ecological, and behavioral characterizations of these cells. Phylogenetic analysis of S. stipatus spec. nov. by comparison of SSU rDNA sequence suggests it is a distinct species from its closest relative, S. amethystinus. We demonstrate that S. stipatus spec. nov. is capable of habituation in response to repeated mechanical stimulation. Further, S. stipatus spec. nov. exhibits strongly directed positive phototaxis, like its relative S. pyriformis, but with a distinct action spectrum from both S. coeruleus and S. pyriformis. Finally, S. stipatus phototaxis response strength varies in a consistent pattern throughout the day, providing evidence of potential circadian regulation. This work expands the current understanding of the ecological distribution of and behavioral features present within genus Stentor.

Indexed as

CiliophoraHabituation, PsychophysiologicPhototaxisDNA, RibosomalPhylogenySpecies SpecificityDNA, RibosomalCell behaviorCell learningHeterotrichMorphologyPhylogenyProtistSSU rDNAStentor

Identifiers

PMID41720861
PMCPMC13022238

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.