Showing posts with label algae. Show all posts
Showing posts with label algae. Show all posts

26/06/26

𝘔𝘰𝘢𝘳 Protocryptomonas species: Protocryptomonas ellipsoidea Skvortsov 1969 and "Protocryptomonas obovatus Skvortsov 1960"

I wasn't planning on writing a post for two taxa, but the goal is to do it quickly. It's really a "filler" genus I chose to reach my sub-goal of 30 illustrations. And I plan to do the same for other genera in the Cryptomonadaceae family.

Both species belong to the genus Protocryptomonas. If you want more context about the genus (where I explain some of the taxonomic uncertainties surrounding it) and the type species (P. mukdenensis), then visit the page dedicated to P. mukdenensis.

Friendly screamer!: The illustrations are free to use under CC BY-SA 4.0, non-commercial, attribution required (DOTkamina 2026).

Taxonomically, Protocryptomonas is a genus that, along with others (including Cryptomonas, of course), belongs to the family Cryptomonadaceae, order Cryptomonadales, class Cryptophyceae (commonly called "cryptomonad algae"). You know where this is going: cryptomonad algae are then included in the subphylum Rollomonadia, phylum Cryptista, subkingdom Hacrobia, kingdom Chromista. 

The kingdom Chromista is related to the clade Archaeplastida, which includes algae that are relatives and ancestors of plants. You might also encounter another classification, where the phylum Cryptista is included in the clade Pancryptista, which is related to Archaplastida, and both form the large CAM clade. But that's not really important; the point is that Protocryptomonas is another distant relative of plant ancestors.

The references I used to write this post and also to create these illustrations are the following:

Let's get quick: here I present two species, Protocryptomonas ellipsoidea and Protocryptomonas obovatus.


The first entry in this post: P. ellipsoidea appeared in the 1968 article by good old Skvortsov. It is also recognized in AlgaeBase as Protocryptomonas ellipsoidea Skvortsov 1969. In that article, he mentions, and emphasizes, that the difference between P. ellipsoidea and the other two species also described there (P. obovata and P. chilomonoides) is its ellipsoidal shape. To me, that seems a rather vague distinction.

I think it's more noteworthy to highlight that P. ellipsoidea has two flagella, where the primary flagellum is twice the length of the cell, and the secondary flagellum is 1.5 times the length of the cell (in P. mukdenensis, the secondary flagellum was almost the same length as the cell). The cell's dimensions, by the way, are 11 to 18 microns long and 7 microns wide. It is also mentioned that the cell moves rapidly and in a rotational fashion.

The central nucleus, of course, I also omits the nucleolus. The contractile vacuole near de flagellar bodies.

The reticulated mitochondrion, Golgi apparatus, endoplasmic reticulum, and hypothetical vestibulum are represented. These structures should exist in cryptomonad algae species, but there is no direct evidence for this species (nor for the genus Protocryptomonas), so their shapes and sizes are speculative.

In Skvortsov's (1968) article, the description of P. ellipsoidea makes no mention of starch granules, so I based my representation on the general description of the genus Protocryptomonas (5 to 10 starch granules) and also used Figures 7 to 9 from that article, where the specimens have 3 to 7 starch granules of highly variable size, with some being larger than others and others roughly the same size. I have used Figure 9 as a base in combination with Figure 8, to represent, in my case, 6 starch granules, where one is very large and the rest are more medium-sized.

P. ellipsoidea was found in autumn in a cold-water pond near the city of Harbin. Its distribution is inferred to be in northern Manchuria, China.


Okay, now let's talk about the other species, "Protocryptomonas obovatus Skvortsov 1960." I've put it in quotation marks because it doesn't actually have a formally accepted taxonomic name. It's not even accepted in AlgaeBase. It appears alongside the description of P. mukdenensis in Skvortsov 1960.

Before continuing, I must clarify that the name "P. obovatus" is not the same as the other name "P. obovata" mentioned in Skvortsov 1968; that appears to be a different species with different characteristics. You will see this in a future post.

... So P. obovatus It's 12 to 13 microns long and 8 microns wide. The flagellar dimensions are similar to P. mukdenensis: the primary flagellum is twice the length of the cell, and the secondary flagellum is almost the same length as the cell. It has a central nucleus and a contractile vacuole near the flagellar bodies. The vestibulum, endoplasmic reticulum, mitochondrion, and Golgi apparatus are hypothetical in this illustration.

The major difference is that P. obovatus has "numerous starch granules scattered in the anterior part" of the cell. No exact number is mentioned; in Figure 19 of Skvortsov 1960, I would swear there are 20 to 21, and in the posterior region of the cell there are smaller dots that I honestly don't know what they are, but they can't be starch granules because the original description itself says they are "in the anterior region," not the posterior. I haven't represented those mysterious dots. But I have represented the starch granules; I would swear there are about 20.

P. obovatus was found in a lake near Mukden (present-day Shenyang), and its distribution is inferred to be in Northeast China, Liaoning Province. The same applies to P. mukdenensis.

And well, that's all for this post. It took me a while to write it because I was playing some "The Floor is Lava" games on Roblox. Remembering things, I guess, although I don't know what I'm supposed to remember there.

¯\_(⊙︿⊙)_/¯

Protocryptomonas mukdenensis Skvortsov ex C.E.M.Bicudo 1989

This post was originally going to be dedicated to another Cryptomonas species, specifically Cryptomonas marssonii, but I'm having some trouble representing the chloroplast (I think I'm going to have to rearrange layers or something, i'm about to get polymerized at this point with this shit).

So I started reviewing the taxonomy that includes the Cryptomonas genus and found that there are a ton of species and genera, some of them quite obscure. What if I tried to represent them?

And so begins the context for this genus, Protocryptomonas. It's considered a "rare" genus, but only because it lacks detail. No preserved specimens exist; all that remains are the illustrations and descriptions made by Skvortsov. Therefore, the genus is questionable, as to whether they are truly cryptomonads. The question, it seems to me, also lies in whether it's a true genus, or a form of a better-known species, but since only illustrations remain, not much can be determined. It amuses me that, despite everything, the genus and species were accepted taxonomically based solely on the images. You can read more about this in Bicudo (1989).

Friendly (abusive) reminder!: The illustrations are free to use under CC BY-SA 4.0, non-commercial, attribution required (DOTkamina 2026).

Taxonomically, Protocryptomonas is a genus that, along with others (including Cryptomonas, of course), belongs to the family Cryptomonadaceae. I don't have much more to add there, so what follows is a copy-paste of other descriptions of Cryptomonas species:  family Cryptomonadaceae is included in order Cryptomonadales, class Cryptophyceae (commonly called "cryptomonad algae"). You know where this is going: cryptomonad algae are then included in the subphylum Rollomonadia, phylum Cryptista, subkingdom Hacrobia, kingdom Chromista. 

The kingdom Chromista is related to the clade Archaeplastida, which includes algae that are relatives and ancestors of plants. You might also encounter another classification, where the phylum Cryptista is included in the clade Pancryptista, which is related to Archaplastida, and both form the large CAM clade. But that's not really important; the point is that Protocryptomonas is another distant relative of plant ancestors.

I should mention that my references for the text and images are:


Well then, to begin discussing this species, let's start with some general information about the genus. I have based myself on the most current description which is the one in AlgaeBase 2023, and it continues like this: "Free-swimming, biflagellate, dorsiventrally asymmetric monads; with a firm, smooth, hyaline periplast; elliptic or obovate with rounded ends; non-metabolic; flagella unequal, subapically inserted, one twice the cell length, the other one and one-half times the cell length; chloroplasts absent; with five to ten spherical starch grains; a single contractile vacuole near the flagellar bases; A little known freshwater genus recorded only from cold water ponds, impure ditch water and standing water near Harbin, northern Manchuria, China".

Some of these general characteristics are those I have represented for M. mukdenensis Skvortsov ex C.E.M.Bicudo 1989, which is the type species for Protocryptomonas. The central nucleus is visible (I have decided not to depict a nucleolus, as I don't know if one exists or should exist), as is the contractile vacuole near the "flagellar bases" (this leads me to believe it's near the basal bodies, which anchor the flagella to the cytoplasm, but I haven't depicted them). Bicudo (1989) mentions that there are "two contractile vacuoles," although the original descriptions by Skvortzov (1960) only mention one, and AlgaeBase also mentions one, so I'll conclude that there is only one contractile vacuole.

However, in Skvortzov (1960), the descriptions are in Latin and Chinese XDDD. But roughly translated by machine (thanks a lot, Google Translate!), it says the following about Protocryptomonas mukdenensis: oblong or ovate cell shape, 13 to 15 µm long, 7 to 9 µm wide.

Two flagella at the anterior end, the primary one twice as long as the cell, and the secondary one almost the same length as the cell. That's how I've represented them, with the secondary flagellum as if it were "ventral" to the primary one. This arrangement isn't mentioned anywhere; it's an inference derived from how I've been representing the flagella in the Cryptomonas illustrations (the ventral flagellum is shorter, and the dorsal one is longer).

So that's where the analogy comes in. According to Clay (2015), the vestibulum exists in all cryptomonads, and that would also include Protocryptomonas, but there's no actual data or evidence for that, so the vestibulum is highly speculative, which is why it's marked with a question mark and the text is transparent. The same applies to the reticulated mitochondrion, the endoplasmic reticulum, and the Golgi apparatus. These structures should be present in most eukaryotes, but I'm not sure if they exist in Protocryptomonas, given the shapes and sizes I've used to represent them. That's why they're speculative and presented in transparent text. If anything is more relevant, I'd say the reticulated mitochondrion, as Clay (2015) suggests that cryptomonads have this form. However, it's still entirely speculative for Protocryptomonas because there's no direct ultrastructural evidence.


In the general description for Protocryptomonas, AlgaeBase (2023) mentions 5 to 10 spherical starch grains (the organism lacks chloroplasts, and in my opinion, any other type of plastid). But for P. mukdenensis specifically, Skvortzov (1960) mentions that "Cellula oblonga vel ovata; granula amylaceae magna singula," or in Chinese if you prefer: "細胞長橢圓形或卵形;澱粉粒大,單一," which apparently means that the cells have large, individual starch granules. I assume that each cell has a single starch granule, which, according to the same article, is half the size of the cell and has the same width as the cell.

... So it's a huge thing, and it can't mean that each cell has "a few individual granules" because the cell would be too swollen and would have to be larger. Either that, or I simply don't know Latin or Chinese, which is true. So if you're reading this and think I'm misinterpreting everything, let me know in the comments here or on the Wikimedia discussion! Or something like that; sooner or later I'll see it and might correct it.

So, the conclusion is that I've represented P. mukdenensis with only one large starch granule. Since the image is designed as if viewed ventrally, the nucleus is dorsal and the starch grain is "ventral," as if it were covering the nucleus. Actually, this is just an assumption; I'm not saying it necessarily applies to all of them. It's something I inherited from how I've represented Cryptomonas species, with the chloroplasts "covering" the nucleus, which is "behind," although what actually happens is that the chloroplasts "envelop" the nucleus like a sandwich. Protocryptomonas doesn't have chloroplasts—uhm, did I already mention it doesn't have chloroplasts?


And well, I suppose that's all I had to explain about this organism. It lacks other structures present in Cryptomonas or other genera. It does not have ejectisomes or a furrow/gullet system. More details providing context for Protocryptomonas are supposed to be found in this reference: Castro, A. A. J. d., C. E. d. M. Bicudo & D. d. C. Bicudo, 1991. Cryptogamos do Parque Estadual das Fontes do Ipiranga, SaoPaulo, SP. Algas, 2: Cryptophyceae. Hoehnea 18: 87–106. But unfortunately, I have not been able to access that reference.

What do you do in these situations? 

Well. Open Roblox. 

10/06/26

Cryptomonas borealis Skuja 1956

This is an organism I've wanted to illustrate for a while because it seemed interesting compared to other Cryptomonas species, with the "borealis" part and all that. I don't really have much energy to write this post, but I'll try anyway. Then, to feel less guilty, I'll see if I can get around to writing something for the final project. I should notify my supervisor for another mandatory review next week. What follows is a notice regarding the use of the images and taxonomic context, which is almost entirely copied and pasted from the other Cryptomonas guides, so don't expect much ingenuity there.

This species belongs to the family Cryptomonadaceae, order Cryptomonadales, class Cryptophyceae (commonly called "cryptomonad algae"). You know where this is going: cryptomonad algae are then included in the subphylum Rollomonadia, phylum Cryptista, subkingdom Hacrobia, kingdom Chromista. 

The kingdom Chromista is related to the clade Archaeplastida, which includes algae that are relatives and ancestors of plants. You might also encounter another classification, where the phylum Cryptista is included in the clade Pancryptista, which is related to Archaplastida, and both form the large CAM clade. But that's not really important; the point is that Cryptomonas borealis is another distant relative of plant ancestors.

bleeeeeh (˶˃ ᵕ ˂˶)

The following illustrations depict Cryptomonas borealis Skuja 1956, as the name is recorded on AlgaeBase. I have shown it in ventral view. The images are free to use and are also available on Wikimedia Commons. Of course, commercial use of these images is not permitted, nor is their use without proper attribution. "DOTkamina (2026)" is sufficient.

For the creation of these illustrations, as well as the text describing them, I have relied on and consulted the following works:

Cryptomonas borealis is a rare species of Cryptomonas

Actually, it's not rare in any particular way; I just said that because the name sounded legendary. "B o r e a l i s"—few things surpass that in epicness. The C. borealis cell is oval with a wavy surface. In fact, I would describe it more accurately, in lateral view, as a kind of rectangular oval that has been bruised. It measures 20 to 50 µm in length.

The organism has two chloroplasts ranging in color from brownish to olive green. One would assume that both chloroplasts are the same color in each individual. In the ventral view, however, I have depicted each chloroplast as a different color: the "ventral" one more greenish and the "dorsal" one more brownish. But I'm sure that doesn't happen in real life. I made that decision to make it easier to distinguish both chloroplasts in the ventral view, but it doesn't mean they are bicolored in real life.

There are no pyrenoids; what exist are several hexagonal or oval starch granules. In the illustrations, I distinguish between "chloroplast 1 starch grains" and "chloroplast 2 starch grains," but this is purely for didactic purposes and to facilitate the separation of the two chloroplasts in the drawing. In reality, the starch granules of both chloroplasts should not differ in size, quantity, or color.

Furthermore, according to Clay (2015), I have represented two nucleomorphs as they are assumed to exist in Cryptomonas (one for each chloroplast, if there are two chloroplasts). Of course, their shape and location are almost speculative. Clay (2015) mentions that they are "between the pyrenoid and the nucleus," but I have represented them as being above the nucleus, since there are no pyrenoids in this species.

One notable feature of this species is the "gullet mouth," which is "widely open." This can be understood as the anterior part of the cell, where the vestibulum and gullet are located, being especially wide. It doesn't end in a "point" or a "curve" as occurs in other Cryptomonas species. In fact, from a lateral view, it literally resembles two jaws or "protrusions" surrounding the entrance (vestibulum), like "a fish with its mouth open," according to Kreutz (2021). I believe I've managed to represent this in my illustration, but you can check Kreutz (2021), Figure 1b, to get a better visualization. Furthermore, this arrangement results in one side of the cell around the vestibulum appearing more "prominent" than the other. In this case, the more prominent side is the dorsal side; you'll see that it's higher on that side than on the ventral side. This prominent area is known as the "apical rostrum."


The gullet, btw, reaches up to half the length of the cell and is covered with ejectisomes, as is common in other Cryptomonas species. In the illustrations of the organism in Kreutz (2021) and Javornický (2014), it appears that the ejectisomes do not completely cover the gullet; rather, there is a portion closer to the exterior ("the vestibulum") that is not covered by them. And that is how I have represented it.

The vestibulum has a "vestibular ligule," a characteristic of campylomorphic Cryptomonas species, such as C. borealis. However, this structure is almost speculative because it has not been reported for this specific species; rather, it is a characteristic that is "assumed" for campylomorphic Cryptomonas. You can learn more about this morphology in the entry on Cryptomonas obovata.

According to Hoef-Emden and Melkonian (2003), the furrow is curved, and I would venture to say that it extends to just under half the length of the cell, based on what I can observe in Hoef-Emden and Melkonian (2003): Figures 2 and 10. That is my main excuse for having depicted the large furrow.

Two Maupas bodies are represented, although the species can have as few as one, or even as many as three. The contractile vacuole is located anteriorly, beneath the apical rostrum. There is also a nucleus with a nucleolus located posteriorly, "in posterior third" (Kreutz 2021). I assume the nucleolus exists because, according to Clay (2015), in cryptomonads during interphase (the "normal" phase of cell life where it is not dividing, but simply existing), the nucleolus is "prominent and persistent."

I have drawn the endoplasmic reticulum, Golgi apparatus, and the single reticulated mitochondrion. The shapes of these structures are speculative. In the case of the mitochondrion, it's a predicted reticulated shape based on what Santore and Greenwood (1977) explains, where it's mentioned that Cryptomonas has a single mitochondrion with numerous branches distributed throughout the cell, concentrated in areas like the gullet. It's assumed that these mitochondrial branches should have different thicknesses in various sections, but in my drawing, the width of these branches is almost uniform.

I assume that the flagellar arrangement in C. borealis is type 4, as described in Kugrens et al. (1987): this means: the flagella do not follow the basic type 1 flagellar arrangement (long dorsal flagellum with two rows of mastigonemes, each with a terminal filament; short ventral flagellum with one row of mastigonemes, each with two unequal terminal filaments). Instead, there is a type 4 flagellar arrangement. In this arrangement, there is only one row of mastigonemes for both flagella. The nature of the terminal filaments is the same as in type 1 flagella. Therefore: long (dorsal) flagellum with one row of mastigonemes, each with a terminal filament; short (ventral) flagellum with one row of mastigonemes, each with two unequal terminal filaments. Additionally, at the terminal tip of the long flagellum, there are four "terminal hairs".

Kugrens et al. (1987)'s work does not mention that C. borealis has type 4 flagella. I infer this because its morphological relationship with C. curvata and C. platyuris, among other species, has been discussed (Javornický 2014 and Hoef-Emden and Melkonian 2003). And C. curvata and C. platyuris have type-4 flagella. Furthermore, flagellar type 4 in Kugrens et al. (1987) is associated with species described as campylomorphic by Clay (2015)... and C. borealis is campylomorphic and only has this morph according to Hoef-Emden and Melkonian (2003). All of this leads me to believe that C. borealis has this flagellar arrangement. But of course, this is speculative, and electron microscopy studies would be necessary to confirm it.

Both the mastigonemes and the additional filaments and hairs can only be seen with an electron microscope. Don't expect to see them with a light microscope. Even the flagella are sometimes difficult to see with a light microscope. I almost forgot: both flagella are located on the right side of the vestibule. That's from a dorsal view. In a ventral view, they appear to be on the left, but that's just an illusion!

I really think that was all I had to say about this species. I've had it ready for a long time—I mean, the illustrations—but I was too lazy to write it. Thankfully, I'm finally out of writer's block.

15/05/26

Porphyridium purpureum (Bory) K.M.Drew & R.Ross 1965

Well, it's an honor to begin the third set of illustrations with the 21st organism to be illustrated, and that honor goes to this single-celled red alga. Given how well-known it is and all the research surrounding it, I'm surprised it hasn't yet had an image representing it in its article. So, I saw the opportunity and took it.

Reminder that it is free to use under CC BY-SA 4.0, non-commercial, attribution required (DOTkamina 2026).

◝(๑꒪່౪̮꒪່๑)◜

Well, this is a single-celled red alga from the family Porphyridiaceae, order Porphyridiales, class Porphyridiophyceae, subphylum Proteorhodophytina. Within this subphylum, it shares characteristics with other groups of red algae, both filamentous and pseudofilamentous, which definitely appear larger due to their more multicellular organization. 

Finally, it belongs to the phylum Rhodophyta, which includes all red algae, and these are further classified within the infrakingdom Rhodaria (red algae and their relatives, which are basically Rhodophyta along with Picozoa and Rhodelphidia—guess what?—the first protists I illustrated!), subkingdom Biliphyta (which would encompass Rhodaria and Glaucophyta). 

Anyway, this subkingdom Biliphyta is considered obsolete according to Wikipedia, but AlgaeBase still uses it. The important point is that Rhodaria, along with Glaucophyta and Viridiplantae (plants and relatives of plant ancestors), these three clades, make up the large clade Archaeplastida. Archaeplastida, together with Pancryptista (class Endohelea and phylum Cryptista, which includes the cryptomonad algae I have illustrated several times previously), make up the large CAM clade.

The sources I used and read for the creation of the image, as well as the text where I explain it, are these:

Seen this way, it seems like an impressive bibliography, but most of it was mainly to learn for the first time about the anatomy of the organism, as well as aspects of its life, or other general topics. Anyway, here's the illustration:


Well, what can I say about this organism? The most striking feature is its stellate chloroplast, meaning it has a shape close to a star, although to me it looks more like an egg smashed on the floor. In the illustration, I've depicted the chloroplast with a series of curves inside, and these curves represent the thylakoids. In the center of the chloroplast is a pyrenoid of a darker tone. I don't know if the pyrenoid is actually darker than the chloroplast; in the micrographs I've seen, I haven't observed much difference in tone. What I do know is that the pyrenoid has some internal "curves" (which I've drawn) that aren't as compact as the curves (thylakoids) of the chloroplast. I have no idea what those thylakoid curves are (see images in Efimova et al. 2014; Gantt and Conti 1965; Gantt and Conti 1966; Markina et al. 2021; Nelson and Ryan 1988).

Other important organelles: the nucleus, of course, which has a nucleolus... or at least that's what I infer from what I see in the micrographs by Markina et al. 2021. Of course, in that article, the micrographs correspond to P. purpureum stressed by the presence of copper. But in another micrograph of Porphyridium cruentum, a distinctive area of ​​the nucleus is evident, which I assume is the nucleolus (see Gantt and Conti 1966). So I've depicted the nucleus with a nucleolus.

The other organelles tend to be located at the cell's periphery, not in the center (Efimova et al. 2014). Both starch grains and lipid bodies are present, and the latter are darker (according to Efimova et al. 2014). Starch grains are also included as peripheral structures, but I've depicted them more dispersed, in homage to the micrograph by Gantt and Conti (1966). It's important to understand that in my illustration, these starch grains are "in the periphery above the cell's center," not literally in the center.




The Golgi apparatus is also located at the periphery, according to Efimova et al. (2014), and I've depicted it as such, made of dictyosomes (the sacs) with attached vesicles. I've also depicted the mitochondria. According to Efimova et al. 2014, there are several tubular mitochondria. This feels strange to me because in most of my previous illustrations, I was getting used to the "single reticulated mitochondrion" scheme. It's a bit of a shock that this isn't the case in P. purpureum. These mitochondria are also distributed in the periphery. I've depicted the mitochondrial cristae as if they were tubular, but for that, I based my work on P. cruentum (see Gantt and Conti 1965). 

For the endoplasmic reticulum (or as Gantt and Conti 1965 call it, "endoplasmic reticulum"), I also relied on their description of P. cruentum: "neither extensive nor elaborate." That's why you'll see that I've depicted it peripherally (which actually means it's in contact with the cell surface and also with the nucleus, of course), and very simply, with relatively short "branches." I assume they must be similar across species.

Finally, the cell is enveloped in an "extracellular polysaccharide sheath," which is, indeed, just that: a thick mucilage covering made of pectins. In actual micrographs, you can identify this structure as a kind of transparent "aura" or "areola" visible around the cell.

I think there's nothing more to say about this organism. I hope my computer doesn't crash so I can upload the images, because it's already night ೭੧(❛〜❛✿)੭೨

06/05/26

Cryptomonas paramaecium (Ehrenberg) Hoef-Emden & Melkonian 2003 = Chilomonas paramaecium Ehrenberg 1831

This organism is a hoax. It has supposedly already been reclassified as another species of Cryptomonas campylomorph form (no cryptomorph has been found), but in any case, AlgaeBase still considers it the type (lectotype) of the genus Chilomonas, since it was previously considered part of that genus, different from CryptomonasThere is another name used, which is "Chilomonas paramecium", instead of "paramaecium". It appears as such in Clay (2015).

This species belongs to the family Cryptomonadaceae, order Cryptomonadales, class Cryptophyceae (commonly called "cryptomonad algae"). You know where this is going: cryptomonad algae are then included in the subphylum Rollomonadia, phylum Cryptista, subkingdom Hacrobia, kingdom Chromista. 

The kingdom Chromista is related to the clade Archaeplastida, which includes algae that are relatives and ancestors of plants. You might also encounter another classification, where the phylum Cryptista is included in the clade Pancryptista, which is related to Archaplastida, and both form the large CAM clade. But that's not really important; the point is that Cryptomonas paramaecium is another distant relative of plant ancestors.

Reminder that it is free to use under CC BY-SA 4.0, non-commercial, attribution required (DOTkamina 2026). The sources I used and read for the creation of the image, as well as the text where I explain, are these:

As I mentioned, C. paramaecium has a campylomorph form. This means a simple furrow without stomata and an almost sigmoid cell shape, although in this species, the shape is usually more ovate-elongated and slightly wider anteriorly. The vestibulum has a vestibular ligule (this ligule is absent in the cryptomorph form in another species). The furrow is quite small compared to others.

Most notably, it lacks chloroplasts and pyrenoids, instead possessing leucoplasts with starch grains and nucleomorphs (one in each chloroplast). Therefore, it doesn't have a red or green pigment to give it color; it is transparent (though under a microscope it appears grayish or glassy). In this image, I've used various grayish to bluish tones and other minor colors, but it's important to remember that the objective is more didactic than realistic.

Dimensions: 14–28 µm long × 10–13 µm wide × 8–10 µm thick. However, Clay (2015) attributes larger sizes to it, 20–40 µm long and 10–20 µm in diameter.

Other observed features include the contractile vacuole at the anterior extreme of the cell, two Maupas bodies located approximately in the cell's central region, and the gullet surrounded by ejectisomes (few are illustrated in Clay (2015), but more are seen in the micrographs by Kreutz (2021).

According to Kreutz (2021), flagella are slightly shorter than the cell and the same length, but in the illustrations from both that source and Clay (2015), they are depicted as shorter relative to the cell, and I have represented them accordingly, choosing to make them approximately half the size of the cell. Although both are equal in length (again, in the illustrations in Kreutz (2021) and Clay (2015), they are not depicted at the same lengths), I have chosen to represent the longer flagellum slightly longer than the shorter (ventral) one.

I have drawn the endoplasmic reticulumGolgi apparatus, and the single reticulated mitochondrion. The shapes of these structures are speculative. In the case of the mitochondrion, it's a predicted reticulated shape based on what Santore and Greenwood (1977) explains, where it's mentioned that Cryptomonas has a single mitochondrion with numerous branches distributed throughout the cell, concentrated in areas like the gullet. It's assumed that these mitochondrial branches should have different thicknesses in various sections, but in my drawing, the width of these branches is almost uniform.

According to Kugrens et al. (1987): unlike other species, the flagella do not follow the basic type 1 flagellar arrangement (long dorsal flagellum with two rows of mastigonemes, each with a terminal filament; short ventral flagellum with one row of mastigonemes, each with two unequal terminal filaments). Instead, there is a type 4 flagellar arrangement. In this arrangement, there is only one row of mastigonemes for both flagella. The nature of the terminal filaments is the same as in type 1 flagella. Therefore: long (dorsal) flagellum with one row of mastigonemes, each with a terminal filament; short (ventral) flagellum with one row of mastigonemes, each with two unequal terminal filaments. Additionally, at the terminal tip of the long flagellum, there are four "terminal hairs".

Both the mastigonemes and the additional filaments and hairs can only be seen with an electron microscope. Don't expect to see them with a light microscope. Even the flagella are sometimes difficult to see with a light microscope. I almost forgot: both flagella are located on the right side of the vestibule. That's from a dorsal view. In a ventral view, they appear to be on the left, but that's just an illusion!

I have nothing more to say in this post about this organism. In theory, this was supposed to be the entry about Giardia duodenalis, but I had some anatomical questions about its microtubules and I'm investigating it to see if I need to make any further corrections. 

Anyway, that's how, with this organism, I've reached illustration number 20 out of the 100 I have to complete. But hey. It's more fun to say I'm 80 short than 96.

01/05/26

Hatena arenicola N.Okamoto & Inouye 2006

I'm happy to report that despite everything, I was finally able to find the time to finish this illustration and break out of my 20-illustration slump. I actually have another one ready from last year, but I want to save that one for later; in fact, I hope to explain it in a future post. And I apologize for any discomfort or strangeness you may have felt.

In this post, I present the illustrations I've created of Hatena arenicola N.Okamoto & Inouye 2006. The illustrations are free to use under CC BY-SA 4.0, non-commercial, attribution required (DOTkamina 2026).

It belongs to the family Katablepharidaceae, order Katablepharidales, class Katablepharidophyceae, which is part of the subphylum Rollomonadia. This means that Hatena arenicola is related to cryptomonad algae (class Cryptophyceae) and goniomonads (class Goniomonadophyceae), which are also within Rollomonadia. Aside from that, it's the same story I've explained in other posts: Rollomonadia belongs to the phylum Cryptista, clade Pancryptista, and CAM clade. The latter includes Archaeplastida as the sister group to Pancryptista, and encompasses the plants and algae related to its ancestors. Therefore, Hatena arenicola is a distant relative of plants. It's also worth mentioning that another way to classify it is to include the phylum Cryptista as part of the subkingdom Hacrobia, kingdom Chromista, and superkingdom Corticata, where the other kingdom is Plantae. But anyway, the conclusions regarding relationships are almost the same.

I consulted a single source for the morphological and descriptive information of Hatena arenicola, as well as the primary source for the illustrations: "Hatena arenicola gen. et sp. nov., a Katablepharid Undergoing Probable Plastid Acquisition" by Noriko Okamoto and Isao Inouye (2006).

What's curious about this organism is that it seems to have been left "halfway" in the process of acquiring chloroplasts. To give you some context, it's believed that modern plants evolved from eukaryotes that acquired photosynthetic bacteria (primary endosymbiosis, including the ancestors of Viridiplantae, Glaucophyta, and Rhodophyta) or algae (that is, eukaryotes that already had a photosynthetic bacterium integrated as a chloroplast). This latter case is known as secondary endosymbiosis, and includes Euglenophyta and Chlorarachniophyta (which acquired green algae), as well as Heterokontophyta, Haptophyta, Cryptophyta, Dinophyta, and Apicomplexa (which acquired red algae).

There is some evidence of organisms that have undergone secondary endosymbiosis, but very little about how this process occurred. And that's what makes Hatena arenicola stand out, as it appears to be an organism that hasn't yet fully integrated an alga as an organelle. Instead, it's "halfway" integrated; it has a life cycle where it can live freely, and it captures a free-living alga (of the genus Nephroselmis), which it doesn't digest (as it would with other algae), but rather integrates as another part of its body, in a state of endosymbiosis.

That's why it's best to present the following image as the front page:


The illustration essentially depicts how an individual of Hatena arenicola, lacking a symbiotic alga, possesses a feeding apparatus (predatory phase). It uses this apparatus to ingest the symbiotic alga, which then integrates with it, giving rise to the symbiotic state of Hatena arenicola. Due to the process of acquiring the symbiont, the feeding apparatus disappears. When it needs to divide, the nucleus (originally located posteriorly) shifts to the anterior region. The organism divides, with one daughter cell retaining the symbiont and the other not. This daughter cell without a symbiont will develop a feeding apparatus and continue its predatory phase until it acquires another symbiotic alga, Nephroselmis. The daughter cell that inherited the symbiont can continue its life in the "plant phase," living off the photosynthesis provided by the symbiont, and can divide again, generating one daughter cell with a symbiont and another without. As an additional note, I consulted "Phylogeny and ultrastructure of Nephroselmis and Pseudoscourfieldia (Chlorophyta), including the description of Nephroselmis anterostigmatica sp. nov. and a proposal for the Nephroselmidales ord. nov." by Nakayama et al. (2007) for information on the ventral and dorsal locations of the Nephroselmis symbiont.

That said, it is clear that Hatena arenicola has at least two main states: with a symbiont and without a symbiont. Let's begin with the state with the symbiont stage. Hatena arenicola does not possess a feeding apparatus in this stage. Aside from that, it does have everything else: a furrow from which the flagella emerge (the exact area where they emerge is known as the "flagellar insertion zone"). The flagella are derived from basal bodies, which I haven't shown here. There are two types of ejectisomes: type I (large, arranged in two rows near the flagellar insertion zone), and type II (smaller, distributed in numerous rows throughout the cell, except in the area surrounding the symbiont's eyespot).


In addition to the ejectisomes, it also has a nucleus located in the middle posterior region of the cell (when the cell is not ready to divide), with electron-dense chromatin that is always condensed (i.e., in a heterochromatic state). I've represented this heterochromatin as darker clumps in the nucleus; I think it's more visible in the version without the symbiont, which I'll discuss later. In addition to the nucleus, there is also a single "Golgi body" between the nucleus and the flagellar apparatus (basal bodies + flagella). In Figure 6D, you can see some "lines" within the Golgi body, and that's how I've chosen to represent it as well. Next to the Golgi body, 

I've depicted a lysosome, which is evidence of the predatory lifestyle of Hatena arenicola. It's assumed that this organism lives by preying on other algae until it finds a Nephroselmis symbiont. With other algae, it simply digests them completely, and their scales may remain within the lysosomes. I don't know how many lysosomes there are, but I've only depicted one, containing Pyramimonas scales. In the context of these illustrations, and especially for this one of the symbiotic state, it's assumed that in this specific case, Pyramimonas scales still remain in the lysosome, even after acquiring the Nephroselmis symbiont. Incidentally, when it engulfs Nephroselmis, the latter also undergoes a reduction in its structures, which are digested, leaving remnants such as the (more or less) star-shaped scales of Nephroselmis, which also remain inside the lysosome.

There are many mitochondrial profiles throughout the cell, and the authors think they could be sections or pieces of a single large reticulated mitochondrion, so I've represented it that way. The endoplasmic reticulum is distributed loosely throughout the cell. The article refers to "rough endoplasmic reticulum" that "extends beneath the cell surface," which implies the existence of a smooth endoplasmic reticulum. In other illustrations, I've represented both arrangements of endoplasmic reticulum, but frankly, in this illustration, I was just too lazy (besides, the image was going to become even more oversaturated), so I've left it simply as "endoplasmic reticulum."


And now, the symbiont. Earlier I mentioned that Hatena arenicola literally engulfs the symbiont Nephroselmis. How do the authors know that it actually becomes a symbiont and isn't merely a hijacking of structures and eventual death of the ingested organism? Well, because the symbiont Nephroselmis literally grows inside Hatena arenicola. It's true that it loses several structures, such as flagella, endoplasmic reticulum, and the scales on its cell surface, but in return, it undergoes modifications in its eyespot, its chloroplast grows to almost occupy most of the space in the Hatena arenicola cell, and it develops more pyrenoids, because originally the symbiont only has one. 

This is a response to a symbiotic adaptation in which it must obtain energy from the sun through photosynthesis, but no longer solely for itself, but also for the host (Hatena arenicola). Hence, it develops more chloroplasts, eyespots, and pyrenoids: to generate more energy for both organisms. In exchange, Hatena arenicola loses its feeding apparatus, as it now obtains the energy it needs to live from the photosynthesis of its symbiont. What does the symbiont gain from this? Well, I suppose it gains protection from Hatena arenicola, since it is "covered" by the host.

I should mention that the symbiont's cytoplasm is preserved, although it is called "vestigial cytoplasm." It's not very noticeable in the illustration, but I've drawn it there. Even under a microscope, it's not very visible because most of the symbiont's cytoplasmic space is occupied by the chloroplast itself, which in the article is simply called a "plastid." The life cycle diagram only shows the chloroplast, but keep in mind that in reality, it's not just the chloroplast that exists; it's actually located within the vestigial cytoplasm.

The symbiont's pyrenoids have some invaginations of the chloroplast's thylakoids. I've represented these invaginations as slight convex curves. I haven't shown the thylakoids themselves. The pyrenoids are surrounded by starch sheath, as is common for those who have read the protist posts to date. The symbiont also retains the reticulated mitochondrion, with flat, often degraded cristae (which is why I've represented the cristae as small elliptical spots distributed along the symbiont's mitochondria). The symbiont's nucleus is also preserved, located face-to-face with the nucleus of Hatena arenicola. There are also sacs that resemble those of a Golgi apparatus, but it is thought to be in an inactive or degraded form since it has no associated vesicles. The eyespot, of course, located where the feeding apparatus would be, is conspicuous and made of a single-layered sheet of osmiophilic granules. The eyespot is located beneath the chloroplast membrane.


In the illustration of the symbiont state, I have depicted the symbiont's chloroplast in its most massive form, occupying almost the entire cell space. In the illustration of the non-symbiont stage, the Hatena arenicola structures that do not belong to the symbiont are more clearly visible. Additionally, the feeding apparatus is present, which is actually a microtubular network made of two parts: transverse tubular rings (shown here in pink), and longitudinal microtubules arrayed in a single layer (shown here in yellow). 

Obviously, these are not the actual colors; I represented them this way to make them stand out against the blue background. Within the microtubular skeleton of the feeding apparatus, there are several electron-opaque granules, some large and elongated (light gray), and others smaller, granular, and pigmented (i.e., darker). I've represented both types, but I don't think I've managed to distinguish between them well, and they become barely visible with the colors I used for the feeding apparatus. Oh well, I never passed color theory.


As always, remember that the colors used in these illustrations are more for educational purposes than to accurately represent reality. My ribs are hurting, so I'll stop writing here.

12/04/26

Cryptomonas tetrapyrenoidosa Skuja 1948

I consider this illustration special because my main source for drawing Cryptomonas species is usually the illustrations already in Clay (2015); you can see that my inspiration clearly comes from there. But there isn't a previous illustration of this species, only micrographs that don't provide much information. You could say this is one of my first Cryptomonas illustrations that "almost came from nowhere," except for the text and the limited photographic information available. Yes, this is a paragraph where I declare that I'm proud of what I'm doing.

The illustrations are free to use under CC BY-SA 4.0, non-commercial, attribution required (DOTkamina 2026).

This species belongs to the family Cryptomonadaceae, order Cryptomonadales, class Cryptophyceae (commonly called "cryptomonad algae"). You know where this is going: cryptomonad algae are then included in the subphylum Rollomonadia, phylum Cryptista, subkingdom Hacrobia, kingdom Chromista. 

The kingdom Chromista is related to the clade Archaeplastida, which includes algae that are relatives and ancestors of plants. You might also encounter another classification, where the phylum Cryptista is included in the clade Pancryptista, which is related to Archaplastida, and both form the large CAM clade. But that's not really important; the point is that Cryptomonas tetrapyrenoidosa is another distant relative of plant ancestors.

The information written here, as well as the illustrations themselves, were based on the following sources:

I drew this organism because it had a very long name. Which also gives many clues about its appearance: it has four pyrenoids, two in each chloroplast. Unfortunately, this isn't always the case; the number of pyrenoids can range from 6 to 7. It also has starch grains throughout the cell. By the way, C. tetrapyrenoidosa has two chloroplasts.


Dimensions: according to Clay (2015): 20–60 µm long, 10–27 µm wide, 5–17 µm deep. According to Protist Information Server (2018): 16–25 µm long, 8–13 µm wide, 7–12 µm thick. According to Choi et al. (2013): 16–22 µm long. Hmm, several dimensions to consider.

The name in Choi et al. (2013) should be noted that refers to Cryptomonas tetrapyrenoidosa (Skuja) Hoef-Emden et Melkonian 2003, a name whose equivalence to C. tetrapyrenoidosa Skuja, 1948, the species I have represented here, is uncertain.

According to Protist Information Server (2018), the species has two refractile bodies in the cell center. I am unsure if this term is equivalent to "maupas bodies," as they are technically the same in behavior: two structures found in several species (not only Cryptomonas, but also Chilomonas) that reflect light, hence their white and shiny appearance. However, I have decided to retain the term "refractile bodies" because, let's be honest, I am not an expert on this either. In Clay (2015) Figure 6G, two white oval-shaped circles can be seen in the cell center, which I consider micrographic visual evidence of these structures.


In Clay (2015) Figure 9A, there is an electron micrograph of the cell exterior of C. tetrapyrenoidosa which, thankfully, provides sufficient visual information about the shape of the vestibulum, the flagellar insertion, and the stoma location within the furrow. I have attempted to represent it somewhere between reality (that Figure 9A) and a more "simplified" way within the context of my illustration. I hope this is clear. In the illustration, I refer to the thin black line ending at the stoma as the "furrow," but the rest of the groove (dark gray) surrounding that black line would also be part of the "furrow." My intention was to depict the furrow as a groove-like structure with depth. I don't think I achieved that goal very well, to be honest.

Of course, there is a gullet, which has ejectisomes surrounding it. I don't know the exact arrangement, but I decided to use three rows of ejectisomes because that seems to be "the standard" in Cryptomonas species, according to the Protist Information Server (2018). But assume there can be more. Hey, while I'm at it, did you notice I used a different brush for the ejectisomes? IbisPaint has a special brush that you can temporarily unlock by watching an ad, and it draws like 3D beads. I thought it wouldn't look good, but I already tried it on the Cryptomonas erosa illustration and it turned out great, so I think I'll keep using it for a while longer.

The color is almost speculative, since in the Protist Information Server (2018) the cells appear bright green, but I've illustrated some Cryptomonas species before (not that many, but you get the idea) and they're always around a brownish color, so that's the color I decided to use for this illustration. They're also represented that way in CCAP (n.d.).

Regarding the flagella, their dimensions are almost speculative; I drew them by roughly estimating their size relative to the cell size in Clay (2015) Figure 9A. This time, unlike other species I have already illustrated, I am certain of the arrangement and shape of the mastigonemes on the flagella, since Kugrens et al. (1987) directly mentions that C. tetrapyrenoidosa has type I flagella. And this consists of: the long (dorsal) flagellum has two opposing rows of mastigonemes, each with a single terminal filament. The short (ventral) flagellum also has a single row of mastigonemes, each with two terminal filaments of different lengths. Additionally, there are approximately three terminal hairs at the end of the dorsal flagellum.

Both the mastigonemes and the additional filaments and hairs can only be seen with an electron microscope. Don't expect to see them with a light microscope. Even the flagella are sometimes difficult to see with a light microscope. I almost forgot: both flagella are located on the right side of the vestibule. That's from a dorsal view. In a ventral view, they appear to be on the left, but that's just an illusion!

Additionally, according to Clay (2015)Cryptomonas species generally have two nucleomorphs between the nucleus and the pyrenoids. Unfortunately, C. erosa does not have pyrenoids, so I have drawn the nucleomorphs above the nucleus. The nucleomorphs in this illustration are therefore speculative.

The shapes of the single reticulated mitochondrionGolgi apparatus and endoplasmic reticulum are also speculative. In the case of the mitochondrion, it's a predicted reticulated shape based on what Santore and Greenwood (1977) explains, where it's mentioned that Cryptomonas has a single mitochondrion with numerous branches distributed throughout the cell, concentrated in areas like the gullet. It's assumed that these mitochondrial branches should have different thicknesses in various sections, but in my drawing, the width of these branches is almost uniform.

Will there be rule 34 of my OC?

I should be doing other things right now. Especially since I also have to study some user guides for special cameras. Because, as I mentioned in a previous post, next week I'll be going on a trip that could lead to my first real job. I'm excited about that, as well as about reaching 20 illustrations. I need to hurry and upload these files online and keep expanding my reach.