Urostipulosphaera articulata (Korshikov) Pusztai & Skaloud, 2021

An, Yalu, Hao, Junxue, Nan, Fangru, Lv, Junping, Liu, Qi, Liu, Xudong, Xie, Shulian & Feng, Jia, 2025, New records of the colonial chrysophyte Urostipulosphaera articulata (Chrysophyceae, Ochromonadales) in China, Biodiversity Data Journal 13, pp. e 150900-e 150900 : e150900-

Urostipulosphaera articulata (Korshikov) Pusztai & Skaloud, 2021

Materials

Type status: Other material. Occurrence: catalogNumber: SXU-SX 230512 ; recordedBy: Zhao Kang-Xu; occurrenceID: C0FC4BFE-A7B0-5236-B3E6-A75A70A703A3; Taxon: scientificName: Urostipulosphaera articulata ; class: Chrysophyceae; order: Ochromonadales ; family: Ochromonadaceae ; Location: country: China; stateProvince: Shanxi; county: Taiyuan; locality: the Fenhe River ; verbatimCoordinates: 37.7743 N 112.5378 E; Identification: identifiedBy: An Ya-Lu; Event: year: 2023; month: 5; day: 12; Record Level: type: specimen; language: en; collectionCode: Algae

Type status: Other material. Occurrence: catalogNumber: SXU-SX 230512 ; recordedBy: Zhao Kang-Xu; occurrenceID: C0FC4BFE-A7B0-5236-B3E6-A75A70A703A3; Taxon: scientificName: Urostipulosphaera articulata ; class: Chrysophyceae; order: Ochromonadales ; family: Ochromonadaceae ; Location: country: China; stateProvince: Shanxi; county: Taiyuan; locality: the Fenhe River ; verbatimCoordinates: 37.7743 N 112.5378 E; Identification: identifiedBy: An Ya-Lu; Event: year: 2023; month: 5; day: 12; Record Level: type: specimen; language: en; collectionCode: Algae

Type status: Other material. Occurrence: catalogNumber: SXU-SX 230512 ; recordedBy: Zhao Kang-Xu; occurrenceID: C0FC4BFE-A7B0-5236-B3E6-A75A70A703A3; Taxon: scientificName: Urostipulosphaera articulata ; class: Chrysophyceae; order: Ochromonadales ; family: Ochromonadaceae ; Location: country: China; stateProvince: Shanxi; county: Taiyuan; locality: the Fenhe River ; verbatimCoordinates: 37.7743 N 112.5378 E; Identification: identifiedBy: An Ya-Lu; Event: year: 2023; month: 5; day: 12; Record Level: type: specimen; language: en; collectionCode: Algae

Description

The morphological colonies of Urostipulosphaera articulata from Shanxi Province were usually spherical, sometimes oval, cells posterior exhibited a truncate or rounded shape and they were connected into colonies via a dichotomous branching system of relatively thick gelatinous stalks (Fig. 2 ). The diameter of colonies ranged from 40–196 µm. Cells size varied from 10.8–18 µm long and 5.4–9 µm wide. Cells had a single, spiral, gold-coloured plastid with a red eyespot. The anterior end of the cell had two flagella of unequal length extending out of the cell. The longer flagellum ranges from 12.5 to 23.53 µm and the shorter one is between 3.6 µm and 5.5 µm, which is about 1 / 4 of the longer one. The long flagellum was with mastigonemes (Fig. 3 b). Under the scanning electron microscope (SEM), the stomatocysts were found to be spherical, with diameters ranging from 12.5 to 15.5 μm. The mature cysts had a curved hook collar with irregular globular protrusions on the surface (Fig. 3 g-l). In contrast, the immature cysts had a smooth surface and no complete collar (Fig. 3 c-e).

The diameters of colony from sample SX 230512 ranged from 40 to 120 µm and colonies consisted of tens to hundreds of obovate cells. Cell sizes varied from 10.8 to 18 µm long and 5.4 to 9 µm wide. The diameters of the mature cysts were 12.8–14.2 µm. The colony from sample SX 240513 had a diameter of 83–196 µm, with cell dimensions of 13.09 to 14.29 µm x 5.95 to 7.14 µm. The cysts diameter were 12.56–13.77 µm. The diameter of colony from sample SX 241121 was 52.63–67.85 µm and the cysts were 13.95–15.55 µm, the size of the cell being 11.90 to 13.09 µm long and 5.95 to 7.14 µm wide.

Distribution

Currently known from Germany, Russia, North America and Czechia.

Figures

Figure 2. Morphology of Urostipulosphaera articulata from three localities in Shanxi Province light microscope (LM) images. a-c The sample of SX 230512 morphological structures; d-e The sample of SX 240513 morphological structures; g-i The sample of SX 241121 morphological structures. Scale bar: a, d = 50 μm, b-c, e-i = 20 μm.

Figure 3. Morphological of cells and stomatocysts of Urostipulosphaera articulata from three localities in Shanxi Province (SEM). a Dichotomous branching structure; b Zoom on mastigonemes of long flagellum. c-e immature stomatocysts. d-l immature stomatocysts. Scale bar: a, b, k, l = 10 μm, c, e, f = 5 μm, d = 3 μm,, h, i, g, j = 2 μm.