Klosteria bodomorphis is a free-living protist belonging to the Neobodonidae family, which, as I'll explain later, is related to dangerous kinetoplastid organisms... well, it's not that surprising, but still.
These drawings are free to use and you probably found them on Wikimedia Commons. They are licensed under CC BY-SA 4.0 Attribution-ShareAlike 4.0 International. Free use for non-commercial purposes. You also have to give credit every time you use an image. "DOTkamina 2026" is fine, I think.
Sources: formally just one: "The taxonomic position of Klosteria bodomorphis gen. and sp. nov. (Kinetoplastida) based on ultrastructure and SSU rRNA gene sequence analysis" by Sergey I. Nikolaev, Alexander P. Mylnikov, Cedric Berney, Jose Fahrni, Nikolai Petrov and Jan Pawlowski, Protistology 3 (2), 126-135 (2003)... or simply Nikolaev et al. (2003). It's literally the article where this species is described. Although, to be honest, it was a bit complicated because there were strange concepts I didn't quite understand. That's why I also consulted this book chapter on kinetoplastid microanatomy: "Kinetoplastea" by Gibson, W. (2016).
So... Klosteria bodomorphis belongs to the family Neobodonidae, order Neobodonida, subclass Metakinetoplastina, in the class Kinetoplastea. I don't know what is more unnerving: that Kinetoplastea is included in the phylum Euglenozoa (meaning they are distantly related to the famous microalgae Euglena), or that along with Neobodonida, which includes free-living species that eat bacteria, it encompasses other clades where the titans, the horror of many, reside, such as Trypanosoma and Leishmania (in the order Trypanosomatida).
But with Klosteria bodomorphis, you have nothing to worry about. This is a free-living organism that was isolated from samples taken from the Baltic Sea shoreline, near the town of Kloster, Germany, in December 1994. It's an organism that feeds on bacteria—which ones? I don't know. In the illustration, I depict a specimen of Aerobacter (Klebsiella) aerogenes as prey, and within its food vacuoles, I have drawn amorphous pinkish blobs representing partially digested bacteria of that species. The reason for choosing this specific species is that Nikolaev et al. (2003) used this bacterium as a food source in laboratory culture. However, it is unknown exactly which bacterial species or clades it might consume in nature.
But focusing on its anatomy, I'll begin by saying that it has two heterodynamic flagella: the anterior one measures 12 µm and the posterior one 17 µm. At the end of each flagellum are short, tapering tips known as acronemes. The anterior flagellum is covered with mastigonemes measuring 2 to 2.5 µm. Both flagella are covered by a layer of condensed glycocalyx, but I haven't depicted that.
You already know the typical flagellar configuration: 9+2 (nine doublets of microtubules surrounding two central single microtubules), enclosed by the plasma membrane. More generally, flagella "emerge" from the cytoplasm. In Klosteria bodomorphis, the flagella emerge from a kind of "depression" on the cell surface, surrounding the lower portions of the external flagella. This "depression" is known as a "flagellar pocket," which is shallow and located subapically. According to Nikolaev et al. (2003), flagellar pockets containing four flagella have been found... which is quite disturbing.
Equally disturbing is the microtubule system identified using electron microscopy, which I have represented more accurately based on the text by Gibson (2016). First, it's worth noting that the flagella, or rather, the 9+2 configuration, originate from the basal bodies. The basal bodies are also anchored by flagellar roots (abbreviated "fr" in the image). Hell yeah, fr!
The flagellar root of the anterior flagellum (that is, the one that originates from the basal body of the previous flagellum) is made of 2 to 3 microtubules and then gives rise to the dorsal submembrane band (simply called the "dorsal band"), which is made of at least 25 microtubules. This band, according to Gibson (2016), extends along the entire dorsal side of the cell.
Simultaneously, the flagellar root of the posterior flagellum emerges from the basal body of the posterior flagellum. This root is composed of six microtubules and extends posteriorly (presumably towards the ventral side of the cell) to form the ventral submembrane band (or simply the "ventral band"), composed of 27 microtubules, which runs along the entire ventral side of the cell.
Between the basal bodies are two microtubules that connect them, which I have labeled as the "fibrillar connection" in the illustration. Another interesting microtubular structure is the so-called "MTR band" (microtubular reinforced band), composed of four to five microtubules. It originates at the surface of the flagellar pocket and extends to the cytopharynx, where it is supplemented by additional microtubules. I have depicted two additional microtubules in the illustration, but Nikolaev et al. (2003) do not specify the actual number. I chose that number because I think I see two more than the 5 of MTR (I hope there are 5) in Illustration 16, but in Illustrations 14 and 15 I think I see more... so I don't know xd.
The shapes of the bands are purely illustrative, but their placement is based verbatim on Nikolaev et al. (2003), and primarily visually on Gibson (2016) Figure 3, and Frolov et al. 2021.
The organism has a cytostome (the "mouth" through which food, bacteria, enters), which is essentially the opening through which food enters. This opening connects to the rest of the invagination, the cytopharynx, a tunnel-like structure measuring 1.8 to 2.3 µm. The lower part of the cytopharynx is surrounded by vesicles. This can be called the "cytostome-cytopharynx complex," and it is simply a very complex cellular feature for phagocytosis, since it is in the cytopharynx that food is packaged into food vacuoles. These vacuoles are directed toward the hind part of the cell (the posterior part).
The organism also has a Golgi apparatus, which is located near the basal bodies. The shape of the Golgi apparatus in the illustration is more schematic than realistic. The nucleus with nucleolus, obviously (although I haven't depicted the nucleolus in this image), "lies at the level of the bottom of the flagellar pocket and at the end of the cytopharynx," according to Nikolaev et al. (2003). They also say that the nucleus is vesicular. I don't know exactly what that means; in (cancer) cytology, it refers to cells with loosely packed chromatin, which under the microscope appear to have nothing inside... but I don't know. In my illustration, you'll see that the nucleus has some dark ornaments in the center and others surrounding it. You can assume the one in the center is the nucleolus. This decision was based on Nikolaev et al. (2003): Figure 17. Around the nucleus is the endoplasmic reticulum, both smooth and rough, and its shapes and existence are speculative (I assume they must exist because they are common in all eukaryotic cells).
The mitochondrion have an almost speculative shape. As can be seen in Nikolaev et al. (2003): Figure 18, appears to extend across a significant portion of the cell. The authors debate whether it is truly a single structure or if it might be more branched. I have chosen to depict it as slightly branched. The authors describe the mitochondria as having discoid cristae. The cristae are invaginations of the inner mitochondrial membrane, and their discoid form refers to the fact that these invaginations are shaped like discs with small "peduncles" (pedicellate, see Pánek et al. (2020): Figures 2A and 2F) when the section is longitudinal, and like sausages or cylindrical "bacilli" when the section is transverse. I have represented them almost as if they were seen in transverse section and pedicellate, in the mitochondrion of my illustration.
Now, I mentioned earlier that Klosteria bodomorphis belongs to the large order Kinetoplastea, and you'll read that the most important characteristic of this group is the kinetoplast, a mass of DNA arranged in maxicircles and minicircles (Wang et al. 2025), located within the mitochondria in a specific region, usually near the basal bodies. But this isn't a mandatory feature for all kinetoplastids; it's actually a structure that is repeated in some, and especially studied in species that are parasitic to humans. For other kinetoplastid species, we can speak of "kinetoplasty," a term that encompasses other forms of organization of kinetoplastid DNA (kDNA).
One such form is pankinetoplasty, described as bundles of kDNA isotropically distributed throughout part or all of the mitochondrial lumen (Gibson 2016: Figure 1i)... think of it as more or less elongated groups of kDNA that are present throughout, or almost throughout, the interior of the mitochondrion. In cell biology, "isotropic" refers to the fact that, in any part of a structure, the properties (I suppose physical, shape, optical, chemical, or whatever) will be more or less similar (New World Encyclopedia n.d.).
According to Nikolaev et al. (2003), Klosteria bodomorphis has little DNA within the mitochondrion that can be interpreted as kDNA, and if so, the most appropriate classification would be pankinetoplasty. The reason they give is that the kDNA fibers do not occupy a very prominent space within the mitochondria. The pankinetoplast (and any other type of kinetoplast, really) should appear as dark spots or aggregates within the mitochondria under an electron microscope. I only manage to observe this more or less in Nikolaev et al. (2003): Figures 16 and 18. I imagine these small spots are slightly darker than the cristae... I have represented the supposed "pankinetoplast" of K. bodomorphis as more or less elongated spots, somewhat distributed throughout the mitochondrion... but it is possible that in reality they are even smaller, more insignificant, less observable or noteworthy spots.
Finally, storage substance granules measuring 0.10 to 0.35 µm in diameter have also been observed in Klosteria bodomorphis. These, along with symbiotic bacteria, one of the most cursed aspects of the organism, measure 0.3 to 0.6 µm in diameter. The authors noted cell division in some of these bacteria, and I have indeed depicted such bacterial division in my illustration.
However, this isn't the end. I've forgotten about the trichocysts. In Klosteria bodomorphis, these are elongated and cylindrical. Length: 1.2 to 1.9 µm, diameter: 0.15 µm, with an internal rod of 0.6 to 0.77 µm, which I've represented as a darker area within the trichocysts. Nikolaev et al. (2003) mention that they are located near the ventral side of the flagellar pocket. I suppose I've erred here because I've depicted them more dorsally, near the ventral band. In fact, this is clearer in the image attached next to the main one, titled "Close-up of the flagellar zone," (the image above, without labels) which is entirely inspired by Nikolaev et al. (2003): Figure 13. So... feel free to discuss whatever you like in the comments. I'd be happy to see corrections and possible improvements. My hand hurts right now, and I have a trip planned where I'll be dragging myself along to see if my final project makes any progress, so lol.
There are 8 to 9 trichocysts arranged in a row, also known as extrusomes. This group is known as a "trichocyst battery." In the main image, only two trichocysts are visible, but that doesn't mean there are only two... they're assumed to be viewed from the side, and those two are "covering" the others.
I guess that's all I have to say. I wasn't expecting to do this illustration, because the organism seemed strange to me. I don't even know how I came across this organism; I think I was reading about trichocysts for a previous illustration. I don't know, I just got a sudden urge and said, "Let's do it, or I'll die." Or maybe it was out of pride. Or perhaps it was out of morbid curiosity to see if I'll finally reach 100 illustrations, or even 20. That number 20 looks pretty promising.
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