bornstupid's Favorites

Mag. 400x
Empty semi-cell of desmid Xanthidium scrobiculatum (previously X. cristatum var. scrobiculatum). This taxon is named for the shallow pits (scrobiculae) decorating the face of the semi-cell. In this specimen, 13 scorbiculae form a sideways diamond shape. Two additional scrobiculae are sited within the diamond to the left and right of center. For information and images, see https://botany.natur.cuni.cz/neustupa/stastny-et-al-2013.pdf, p. 405 and Fig. 4.

• A water sample was taken on 5/8/2023, from the shore of Lantern Hill Pond, using a 10µ dip net to enrich for microbes. Air temp. 73°F.

Mag. 100x (1,2,3); 400x (4,5)
...Originally thought this was a flatworm, as indicated by the initial Notes. However, my opinion changed based on the comments of more experienced observers.

Large, multi-color vacuole-filled flatworm (of Suborder Dalytyphloplanida). The outer wall is thick and covered with very fine hair-like processes. Uncertain regarding the ID, especially since I don't see a mouth. For a video, see https://youtu.be/0uItTOfCxN8.

• A water sample was taken on 4/18/2023, from the shore of Avery Swamp impoundment, using a 10µ dip net to enrich for microbes. Air temp. 50°F.

Mag. 400x
5 independently observed specimens. All are similarly sized and have a relatively thick mucilaginous sheath. @karolina noted that it is unlikely these are individual cells of Hyalotheca since a stellate chloroplast would be readily apparent (e.g. https://www.inaturalist.org/observations/74166151).

• A water sample was taken on 1/24/2023, from the shore of Rosemond Lake , using a 10µ dip net to enrich for microbes. Air temp. 42°F.

Mag. 400x
Bicosoeca sp., I think. This is a filter-feeding flagellate housed in a transparent, vase-like lorica, and has an anterior flagellum (for feeding and transportation) and an posterior flagellum that anchors to the base of the lorica and allows the cell to retract into the lorica when necessary. These Bicosoeca are living epiphytically on a colony of diatoms, Asterionella formosa.
For 2 videos see: https://youtu.be/GjPdiDE_VOY and https://youtu.be/vCKK5l6yxFM.
For a fabulous a video and photos of Bicosoeca, see the observation recorded by iNatter closterium_mysterium, https://www.inaturalist.org/observations/145952656#activity_comment_7f982c87-a61d-4cd0-88b0-cf67d9969e39.

• A water sample was taken on 1/24/2023, from the shore of Rosemond Lake , using a 10µ dip net to enrich for microbes. Air temp. 42°F.

Allogromia terricola (Leidy, 1874) syn. Gromia terricola Leidy, 1874 original description), syn. Gromia fluviatilis Dujardin. A terrestrial species of forminefera from an infusion prepared from the soil at the base of my compost heap.

Test spherical to subspherical; smooth or sparsely covered with siliceous particles; yellowish cytoplasm fills the test; aperture not seen; a large nucleus and numerous contractile vacuoles; filopodia long, often enveloping test; on aquatic plants, in moss or soil.

Envelope spheric or subspheric, seldom changing shape; protoplasm habitually covering the surface of the envelop. Pseudopodia numerous, anastomosing. Habitat aquatic plants. Measurements
90-250 um long.

The following discussion is adapted from the reference below.

Foraminifera are unicellular eukaryotes characterized by the presence of granuloreticulopodia and the possession of a membranous, agglutinated, or calcareous test, which is either monothalamous (single-chambered) or polythalamous (multi-chambered) (Loeblich and Tappan 1987). Within monothalamids some species like Reticulomyxa filosa are amoeboid naked forms.

Until 1859, foraminifera were only known from marine habitats, but that year Claparède and Lachmann described a monothalamid foraminifer, Lieberkuehnia wageneri, sampled from an unknown water body in Berlin. It had a smooth flexible test with an entosolenian tube that separated the main cytoplasm mass from the pseudopodial peduncle.

In 1886 Henri Blanc, a Swiss scientist, described another freshwater foraminifer, Gromia brunneri, which he had collected from the bottom of Lake Geneva. This single-chambered species had an agglutinated test, an organic layer covered and/or embedded with foreign, mainly non-organic, particles.

In subsequent years, Eugène Penard, another Swiss protozoologist, described four similar species Gromia gemma and G. squamosa (1899), G. linearis (1902) and G. saxicola (1905) from the same lake. He also described G. nigricans (1902), which he found not far from Lake Geneva in Mategnin and a marsh near Rouelbeau. Penard made permanent preparations of these foraminifera, which are still preserved and available in the Penard Collection of the Natural History Museum of Geneva (Switzerland).

In 1904, Ludwig Rhumbler erected the subfamily Allogromiinae for monothalamous foraminifera characterized by a more or less flexible organic test wall commonly with one or rarely two terminal apertures at either end of the test. He included all described freshwater species in this taxon. In a recent higher ranked classification of foraminifera based on molecular phylogenies (Pawlowski et al. 2013), monothalamous foraminifera were considered as a paraphyletic group that contains agglutinated and organic walled species as well as “naked” amoeboid species and environmental clades with unknown morphological affinities.

Traditionally the organic-walled foraminifera are called allogromiids. Most of them are distributed over a wide range of marine and brackish habitats (Gooday 2002). Freshwater allogromiids with an agglutinated test were originally placed in the genus Gromia by their discoverers, but as its type species G. oviformis is a filose marine species, Rhumbler (1904) transferred three species (G. squamosa, G. nigricans and G. linearis) to Rhynchogromia Rhumbler 1894. He further erected a new genus, Diplogromia, for the other two species having a double test wall: G. brunneri and G. gemma, although without designing a type species for the genus.

De Saedeleer (1934) revised Rhumbler’s classification leaving D. gemma in its genus and creating a new genus Allelogromia for the Rhynchogromia species with G. brunneri as type species. Deflandre (1953) erected the genus Penardogromia for G. linearis, with the argument that it had a homogenous agglutinated test with calcareous particles. Loeblich and Tappan (1960) argued that the classification of De Saedeleer was unacceptable, because G. brunneri had been fixed as the type of Diplogromia by subsequent designation of Cushman (1928). They created the genus Saedeleeria for G. gemma, transferring G. squamosa and G. nigricans also to Diplogromia, but without giving any supporting explanations. Another agglutinated allogromiid, Penardogromia palustris, was described by Thomas (1961) from a freshwater marsh near Bordeaux (France).

Beside these descriptions there have been some scattered records of agglutinated freshwater allogromiids over the years (Grospietsch, 1958, Hoogenraad and De Groot, 1940, Siemensma, 1982, Wailes, 1915; Meisterfeld pers. comm.; Clauss, unpublished) and some photomicrographs available online (Revello, 2015, Protist Information Server, 2016).

Leidy (1879) was the first who described an allogromiid foraminifer, Gromia terricola, from a terrestrial habit. He found this non-agglutinated species “among moist moss in the crevices of pavements, in shaded places, in the city of Philadelphia”. A similar terrestrial organic walled allogromiid Edaphoallogromia australica has been described by Meisterfeld et al. (2001).

Siemensman et al. Taxonomic revision of freshwater foraminifera with the description of two new agglutinated species and genera. European Journal of Protistology. Volume 60, August 2017, Pages 28-44 https://doi.org/10.1016/j.ejop.2017.05.006

Thalassiosira pacifica Gran & Angst, 1931

Phylum: Bacillariophycophyta, Subphylum: Bacillariophytina, Class: Mediophyceae, Order: Thalassiosirales, Family: Thalassiosiraceae.

SEM images of the marine diatom Thalassiosira pacifica Gran & Angst, 1931.

Girdle view: Cells 16.1-28.8 µm (7.0–55.0) µm in diameter. GI = n = 3.
Cells rectangular with rounded low mantle. Valve face flat or slightly concave. Connecting thread about as long as the pervalvar axis.
Valve view:
Loculate areolae in linear (straight), eccentric or fasciculate patterns (curved) rows depending on the diameter of the cell. Central process adjacent to a central areola (annulus).Valve face areolae 10-19 in µm (Hasle and Syvertsen 1996, Li et al. 2014). GI = 14-16 in 10 µm. 20 to 28 areolae in 10 µm (Hoppenrath et al. 2007, not so). Valve face covered by tiny siliceous granules (Hoppenrath et al. 2007). Marginal strutted processes (MSPs) with relatively long and coarse external tubes. GI specimens have a bulbous and coarse flared tip. MSPs 4-7 in 10 µm. GI = 6. Separation between MSPs = 1 µm (GI) Mantle areolae smaller than those on valve face. The height of mantle is about 2–3 areolae (Li et al. 2014). Labiate process positioned as for a marginal strutted process, slightly inside the marginal ring. Labiate process slightly larger than the marginal strutted processes.Valve margin ribbed.
Notes: Mantle areolae smaller than those on valve face. Valve margin ribbed. Distinguished from T. angulata by the ribbed margin and the more closely spaced marginal processes with shorter
external tubes and the location of the labiate process. (Hasle and Syvertsen 1996:37, Mahood et al. 1986, Hoppenrath et al. 2007, Li et al. 2013. (Hoppenrath et al. 2007 –Fig. 45-46, scale bar = 10 µm)

Methods:

Collected by a 20 µm plankton net May 30, 2022 from the Spanish Hills Wharf (N48˚ 59.688’, W123˚ 35.064’), Trincomali Channel, Galiano Island, Southern Gulf Islands, British Columbia, Canada. No fixation. A 7.5 mL sub sample of concentrated cells pipetted into a 50 mL poly centrifuge tube. Added 37.5 mL of 30% hydrogen peroxide and mixed. Three days in hydrogen peroxide at room temp, followed by 5 x 45 mL washes of sterile distilled and deionized water. Pipetted and syringed with further washes of sterile distilled and deionized water using a Swinnex filter holder onto 12 mm glass 0.45 µm filters and attached to 13 mm SEM stub with double sided tape Imaging with a Hitachi s4800 and a Hitachi TM4000 SEMs at the AMF at UVIC. Thank you Ron Read for taking some of tthe SEM images and Elaine Humphrey for SEM support. Adjusted in Photoshop.

References:

Cupp, E. E. 1943. Marine Plankton Diatoms of the West Coast of North America. University of California Press. Berkeley, California.

Gran, H.H. and Angst, E.C. (1931). Planktonic Diatoms of Puget Sound. Seattle, University Press. https://babel.hathitrust.org/cgi/pt?id=uc1.31822010334225&view=1up&seq=3

Hoppenrath, M., Beszteri, B., Drebes, G., Halliger, H., Van Beusekom, J.E.E. , Janisch, S. and Wiltshire, K. H. (2007) Thalassiosira species (Bacillariophyceae, Thalassiosirales) in the North Sea at Helgoland (German Bight) and Sylt (North Frisian Wadden Sea) – a first approach to assessing diversity, European Journal of Phycology, 42:3, 271-288, DOI: 10.1080/09670260701352288

Horner, R.A., Postel, J.R., Halsband-Lenk, C., Pierson, J.J., Pohnert, G. and Wichard, T. 2005.Winter-spring phytoplankton blooms in Dabob Bay, Washington. Prog. Oceanogr. 67 (3-4): 286-313.

Hasle, G.R. & Syvertsen, E.E. (1996). Marine Diatoms. In: Identifying Marine Phytoplankton. (Tomas, C.R. Eds). San Diego: Academic Press.

Guiry, M.D. & Guiry, G.M. 2007, AlgaeBase version 4.2. World-wide electronic publication, National University of Ireland, http://algaebase.org, searched April 10, 2022.

Li, Y. and Lu, S. (2013). The genus Thalassiosira off the Guangdong coast, South China Sea. Botanica Marina; 56(1): 83–110. DOI: 10.1515/bot-2011-0045

Mahood, A.D., Fryxell, G.A., & Mcmillan, M. (1986). The diatom genus Thalassiosira: species from the San Francisco Bay system. Proc. Calif. Acad. Sci. 24: 127–156.

Round, F.E., Crawford, R.M. and Mann, D.G. (1990). The Diatoms, Biology & Morphology of the Genera. Cambridge University Press, Cambridge, UK. pp. 132-133.

Hay, M. B., Pienitz, R., and Thomson, R.E. (2003). Distribution of diatom surface sediment assemblages within Effingham Inlet, a temperate fjord on the west coast of Vancouver Island (Canada). , 48(3-4), 291–320. doi:10.1016/s0377-8398(03)00025-2

Sancetta, C. and Calvert S. E. (1988). The annual cycle of sedimentation in Saanich Inlet, British Columbia:implications for the interpretation of diatom fossil assemblages. Deep-Sea Research, Vol. 35, No. 1, pp. 71-90.

Shim, J. H. (1976). Distribution and Taxonomy of Planktonic Marine Diatoms in the Strait of Georgia, B.C. Phd. Thesis, UBC.

Waters, R. E., Brown, L.N., and MG Robinson, M.G. (1992). Phytoplankton of Esquimalt Lagoon, British Columbia: comparison with west Vancouver Island coastal and offshore waters. Canadian Technical Report of Hydrography Ocean Sciences 137.

Mesodinium species, 35-40 um from the shoreline benthos of estuary Hog Creek. The trichites are particularly well-visualized.

Mesodinium Stein, 1862 (ref. ID; 3540, 3690, 4352) or 1863 (ref. ID; 2013, 4613, 4971)

From Dr. Inaki

Class Kinetofragminophora: Subclass Gymnostomata: Order Haptorida: Family Didiniidae (ref. ID; 2013)
Family Mesodiniidae: Litostomatea (ref. ID; 4971)

[ref. ID; 2013]
Body shape pyriform but divided into two sections by a waist-like furrow. Anterior narrows apically, posterior broadly rounded. Oral aperture apical, cytopharynx with 8 to 12 protruding trichites which are forked at the anterior most end. Somatic ciliation reduced to 2 bands of cilia which arise from the central body furrow. Both bands arise from short oblique rows of kinetosomes, the posterior band consists of rows components of the anterior ciliary band are stiff and bristle-like, those of the posterior band are membranelle-like and project backwards. Macronucleus centrally located. Contractile vacuoles have been reported in both posterior and mid-lateral positions.

A Chlamydoinella species from the intertidal benthos of marine estuary Accabonac Harbor. The tide was quite low affording access to more bottom than usual. Imaged in Nomarski DIC using Olympus BH2 under SPlan 40x objective and in phase contrast using Zeiss Photomicroscope III using Neofluar PH2 40x objective both with variable phone cropping on Samsung Galaxy S9+.

Chlamydonella
Chlamydonella Deroux, 1970 (ref. ID; 2013)
From: https://www.nies.go.jp/chiiki1/protoz/morpho/ciliopho/chl-ella.htm

Class Kinetofragminophora: Subclass Hypostomata: Order Cyrtophorida: Suborder Chlamydodontina
Ciliophora: Cyrtophorida
Oval in outline shape, dorso-ventrally flattened with dorsal surface strongly arched. Somatic ciliation reduced to central surface with a short field of cilia just on the left of the anterior dorsal surface. Oral aperture supported by basket of trichites. On the right of the ventral surface there are several kineties of which 2 curve around the apex. The extreme right kinety is discontinuous in two parts, one in the equator the other just dorsally on the extreme left of the apex. Below the oral aperture is the left field of kineties (10 or more) which traverse the body width. The arrangement of the pre-oral ciliature is a major characteristic of the genus, the kinety just in front of the oral aperture is always Y-shaped and above it lies a second pre-oral kinety which is simply curved. Macronucleus large, centrally located. There are 2 contractile vacuoles, one anterior, one posterior.

Genus Chlamydonella Deroux in Petz et al. (1995) According to the newly-defined diagnosis (Song and
Wilbert 2000a), the genus Chlamydonella is characterized by: Lynchellids without plasmatic protrusions on ventral side; somatic kineties making no noticeable naked gap between left and right areas; perioral kineties continuous or slightly fragmented with leftmost rows parallel to each other, which are arched transversely; cytopharyngeal rods (nematodesmata) toothed. Macro-
nucleus basically dimorphic.

The Chlamydonella in my isolate measure 50 um in average length (range 45-60 um) and are acontractile but flexible, oval to reniform with an anterior left-hand rostrum, sometimes with a tooth-like ledge. They are dorso-ventrally flattened, ventral surface flat, dorsal surface arched except for an anterior flattened region. Somatic cilia restricted to ventral surface consisting of several longitudinal kineties estimated to number 12.
They feature a poorly visualized central ovoid macronucleus and from one to three contractile vacuoles that are arrayed diagonally usually mid to anterior in position. Ingested meals of small algae and occasionally diatoms are present. The indistinct oval cytostome and a very difficult to discern nematodesmal basket are seen only vaguely in screen capture stills. This inability to visualize the cyrtos in vivo and only faintly in silver preparations has been noted in some species even using differential contrast. I have included several screen captures with the cytostome and/or the cytopharyngeal basket marked with an asterisk.

https://www.researchgate.net/publication/236839421
Redescriptions of three cyrtophorid ciliates from marine biofilm, with
establishment of a new genus, Wilbertella nov gen. (Ciliophora : Cyrtophorida : Lynchellidae). Jun GONG and Weibo SONG. Acta Protozool. (2006) 45: 153 -165
https://www.researchgate.net/publication/236839421

Faunistic Studies on Marine Ciliates from the Antarctic Benthic Area,
Including Descriptions of One Epizoic Form, 6 New Species and, 2 New Genera (Protozoa: Ciliophora). Weibo SONG and Norbert WILBERT. Acta Protozool. (2002) 41: 23 - 61 : https://www.researchgate.net/publication/228590356

Mag. 400x
Decorated with distinctive, blunt spines. Small amoeboid test, no pseudopodia visible (Centropyxis)? Pollen grain? Egg? Survival cyst? Small naval mine?

• A water sample was taken on 11/08/2022, from the shore of Lantern Hill Pond, using a 10µ dip net to enrich for microbes. Air temp. 55°F.