User:Chazmatron/Biology
Note: Not 100% accurate, but I've tried to keep it accurate with a lot information from the Piklopedia~.
Bulborb
Intro
Bulborb (Oculus kageyammi russus), previously known as the Spotty Bulborb or Red Bulborb, are large nocturnal predators. They are prominent modern members of the planet PNF-404 and are a part of the Grub-dog family. More than 3 subspecies of the Oculus kageyammi have been found on the planet, with the Bulborb being the original species these other subspecies have evolved from. This is why the creature has a third name, russus to differentiate it from the other organisms. The Bulborb is known to have 3 stages of development: a Bulborb Larva (Oculus kageyamii larva (pre-molt)), an Albino Dwarf Bulborb (Oculus kageyamii larva (1st molt)), and then the Bulborb.
The Bulborb is the most commonly found member of the family Grub-Dog and is further distinguished from other members of the family by its bright scarlet-coloured hide covered with white spots, reminiscent of a ladybird’s backside. General appearance-wise, the Bulborb (along with its variants) has a head that takes up most of its body, two eyes on stalks that are blue in colour - however more eye colours have been spotted, such as purple. They also have a pair of legs with 2 toes on each with moderately sized claws. They also have a yellow-hued face with a pair of nostrils and are equipped with a pair of mandibles that hang outside their mouth, resembling sabre-like teeth. These mandibles are used for breaking exoskeletons of prey insects and digging through the soil for roots. However, they can support a diet of animals and plants as seen through observation; specifically, they have a clear preference for Pikmin and are noted to eat juvenile Bulborbs.
| Taxonomy | Relation |
|---|---|
| Kingdom | Animalia |
| Phylum | Arthropoda |
| Class | Insecta |
| Order | [Unknown] |
| Family | Grub-dog |
| Genus | Oculus |
| Species | Kageyammi |
| Subspecies | K. Russus |
Taxonomy
It was first classified as a Spotty Bulborb until equally spotted variants had been discovered, leading to its second name of Red Bulborb. Recently, people have argued that the creature should just be called a Bulborb due to it serving as the original evolutionary point the other variants have evolved from, such as the Orange Bulborb or the Hairy Bulborb.
Bulborbs are nocturnal creatures and will sleep in open locations during the day. This would lead to them being attacked by potential predators, but due to their large size and bright colours, there is a distinct lack of Bulborb predators. Bulborbs hunt for insects and Pikmin, who are retreating back to their nests/Onions during the early stages of the night. If they are unable to find any insects, the Bulborb shows distinct anger and begins looking for any vegetation to feed on. Their diet is quite varied and is mostly dependent on the region they are located in; they can feed on shrubs and leaves in hotter climates and vegetables and ferns in colder climates.
Description
The Bulborb is the most commonly found member of the Grub-Dog family, and is further distinguished from other Grub-Dogs by its bright red hide covered in white spots - resembling a ladybird’s - as well as its yellowish head and feet. It has a powerful build, capable of eating multiple critters at once due to its mandibles and feet, which are built for standing up at quick speeds. The legs of the Bulborb are built in a way that allows them to stand up at a moment's notice to enable the creature to attack any potential threats or eat any potential prey. The Bulborb has a distinct lack of ears, meaning it can’t hear anything, such as a predator or prey, which would seem like a disadvantage, but due to its bright-coloured spots (acting as aposematism), it tends to deter most creatures. The head of the Bulborb is golden-hued which takes up most of its body mass. It comes equipped with a pair of mandibles, which resemble sabre-like teeth, and a pair of eyestalks.
Ecology
Bulborbs can appear in a multitude of environments, such as distant tundras or tropical wilds; inside caverns or on the surface. There’s no specific environment where Bulborb can’t be found. The main factor that determines a Bulborb’s environment is whether there’s food for it to eat, which is mainly insects, Pikmin, or vegetation. This gives evidence to show that Bulborbs are quite adaptable creatures.
Diet
Similar to other members of the Grub-Dog family, the Bulborb will primarily feed on insects at the early signs of dusk as the insects are returning back to their nests and Pikmin that are left behind after the Onion heads off into orbit for the night. The Bulborb prefers to eat Pikmin of any kind (even White Pikmin and Ice Pikmin - which negatively affects their health) and would look for Pikmin even before searching for insects. If the Bulborb is unable to locate any of the latter, it will instead opt to eat local vegetation, which depends on its region. The Bulborb specialises in preying on the unsuspecting critters, which would be defenceless. Bulborbs in hotter climates would diet on insects such as roaches or ants and can feed on shrubs or leaves from trees. In colder climates they would feed on bugs like termites or cockroaches and eat vegetation such as moss and berries.
Interaction with other creatures
Bulborbs are typically spotted alone, sleeping in their chosen territory, so they don't often interact with other creatures, but they have been spotted with a few other creatures. They have been seen sleeping during the day near some Dwarf Bulborbs (Pansarus pseudooculii russus), which is in fact not a juvenile Bulborb but is instead a Breadbug mimic, which survives via mimicry. Due to this mimicking, the Bulborb can be seen protecting them and has been seen to wake up quickly when a Dwarf Bulborb cries out. However, future sightings have not shown this behaviour.
Bulborbs have also been seen living in close contact with other Grub-Dogs, such as the 2 previously mentioned, as well as a few more. It is unknown how they find food, but it has been proven that a Bulborb will in fact eat true Bulborb larva, which could be a method of how they’ve sustained themselves. In some caves, the Bulborb has been spotted cohabiting with other creatures with a similar diet, such as Blowhogs, which also feed on insects, and yet there’s no fighting for territory occurring. It is unknown at this time why this happens, the main theory being that the Bulborbs and Blowhogs diet on specific and/or different insects.
Infections/Diseases
The main infection that can be carried by Bulborb is parasitic Pikmin. The parasite favours juvenile Bulborbs (not Dwarf Bulborbs - the Breadbug mimic) and will infect the host to take control of the body. It will sport a stem just like a regular Pikmin and can mature the same way as regular Pikmin. There is no known way to cure a Bulborb of the parasite as of 25.10.23. Once infected, the Bulborb - which is called a Bulbmin - will start to behave less like a Bulborb and more like a Pikmin, as it follows a leader (which would be the oldest Bulbmin) and will hunt in groups. Since the Bulbmin don’t have an Onion, it’s possible that the adult Bulbmin gives birth to young Bulborbs, which are born infected. It should be noted that these types of creatures are only, exclusively found in caves and are unable to leave them, which could be due to a multitude of reasons - the main one being that the sun is harmful to them.
Another infection comes from a fungal spore from a Toxstool, which either infects a Dwarf Bulborb or a juvenile Bulborb (unknown at this time). The infected Bulborb - referred to as a Moldy Dwarf Bulborb - has a large bulbous growth of fungal matter on its back, which is highly poisonous. It changes the Bulborb's colours from its red back and white spots to a light blue back and a more bluish-hue of white spots. As a host, it will unconsciously hunt out more food whilst scattering large quantities of spores from the bulbous sac on its back until it stops functioning. After that, the body will mutate into a fungal culture that, after some time, will form a juvenile Toxstool. Similar infections can be seen with the Pyroclasmic Slooch, which, when infected, becomes a Moldy Slooch. It should also be noted that if either of the two infected hosts die near a Toxstool, it will spray them with some spores. These spores will 'revive' the creatures.
Fiery Blowhog
Intro
Fiery Blowhogs (Sus draconus) are creatures resembling a mixture of an elephant and a pig. They are quite commonly located throughout the planet and are found in a large variety of habitats. They are also the most common out of their family, the Blowhog family. There are nine (eleven, including Pikmin Adventure) different species of Blowhog, with the Fiery Blowhog sharing a near-identical appearance to two of them: the Watery Blowhog and the Snowy Blowhog. The Fiery Blowhog is known to at least have 2 stages of development: the Fiery Blowlet, which is a smaller-looking version of the Fiery Blowhog, and the Fiery Blowhog. However, if whilst growing and a hormone imbalance occurs, a Fiery Blowhog can grow to around two to three times the size. This giant Fiery Blowhog is known as a Titan Blowhog.
| Taxonomy | Relation |
|---|---|
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | [Unknown] |
| Order | [Unknown] |
| Family | Blowhog |
| Genus | Sus |
| Species | S. draconus |
Taxonomy
Fiery Blowhogs are cathemeral creatures and are known to be active during both the day and the night. This behaviour is a form of psychological adaptation and is likely evolved to fend off predators, so they are always on alert. Alternatively, they may be cathemeral to suit their diet as they feed on insects hiding within grassy patches or insects wandering through their territory.
Description
The Fiery Blowhog is distinguished from its other family members by its light grey, rubbery, mammalian hide covered in ridges of a darker grey colour. These dark grey lines go across its body, circling off, resembling targets, as it gets closer to its snout, which has a bright red tip. They walk around on four legs, each having a single, brown-coloured toe, that holds their large body. These legs are short and smaller in comparison to their body. Finally, the eyes of a Fiery Blowhog are bright blue and are found on the sides of their body. They (images only) appear to lack pupils and irises and only have a sclera, which is blue. However, since this is from images only, this is likely to be incorrect.
Ecology
Fiery Blowhogs are known to inhabit a multitude of environments, but they are mostly found inside of cavernous areas such as in The Forest Navel or actual caves such as the Crackling Cauldron. These cavernous areas are generally 'earthy' in texture with dirt floors and small patches of vegetation growing, but they have been spotted in 'tiled' areas such as the Shower Room or 'metallic' areas like the Cavern of Chaos. They have been spotted outside of these darker areas, but they aren't as common. Fiery Blowhogs have been spotted in colder climates and tropical climates such as the Valley of Repose and Tropical Wilds, respectively. But these colder areas have more fiery hazards, such as fire geysers, which are theorised to help these Blowhogs deal with the chillier weather.
Diet
A Fiery Blowhog feeds on smaller creatures, such as insects or Pikmin, which it captures by spewing fire from its snout. This fire is created due to an evolutionary adaptation allowing for a specialised gland capable of storing a volatile phosphorus compound. This gland stays at a low-oxygen concentration, keeping the aforementioned compound stable and preventing unwanted combustion from inside the Blowhog. This is achieved through a mixture of specially produced proteins and enzymes that keep the environment of the gland at a low oxygen level. When the Blowhog expels the compound into a high-oxygen concentration, such as the air, the sudden increase in oxygen concentration causes a chemical reaction between the compound and the air, creating the fire. Whilst the phosphorus compound itself is not directly derived from ATP (adenosine triphosphate), the Blowhog’s body uses ATP, often called the 'Universal Battery,' to fuel the certain key processes needed to make and hold this compound. ATP powers the necessary reactions that synthesise the compound from basic compounds, allowing the Blowhog to have an indefinite amount at all times. This complex process means that the Fiery Blowhog can always hunt and feed in its environment, using the fire for any of its needs.
Interaction with other creatures
Fiery Blowhogs are often spotted in groups of two to three but can sometimes be found on their own, so they don't have a high amount of social interactions. One explanation for this behaviour is that they are easily self-sufficient, and being in a larger pack results in a larger competition for prey. They are often spotted alongside Watery Blowhogs and have recently been seen alongside Snowy Blowhogs. This is the same for the Fiery Blowhog's larger counterpart, the Titan Blowhog, and the Snowy Blowhog's large counterpart, called the Blizzarding Blowhog. There has been a large pack of Fiery Blowhogs encountered before, numbering up to six in the pack; however, this has never been seen again. This may be due to the environment this pack was discovered in having high resources available, so there would have been less competition. In some caves, the Fiery Blowhog has been spotted living with other creatures with similar diets, such as Bulborbs, which also feed on insects, and yet no fighting occurs. It is unknown why this behaviour happens, but the main theory is that Blowhogs and Bulborbs have different niches of diet.
Infections/Diseases
Whilst not a disease or an infection, certain Fiery Blowhogs can be hypertrophic, which causes significant physiological changes that result in large changes to the Blowhog's structure and capabilities. The Blowhog's hormonal imbalance, which is what causes the hypertrophy, causes rapid growth and enlargement of the creature's cells and/or organs and an increase in size of the fire-producing glands and the power of said fire. A regular Fiery Blowhog's hormones are heavily regulated (like any other creature), which would control tissue development. Since this is now no longer the case, the Titan Blowhog's tissue development will be disrupted. This disruption is what is causing the enlarged limbs, its wider snout, and the more powerful fire. This disruption, causing the larger tissue regulation, is causing the large body as well. Due to the larger body, the Titan Blowhog would need larger organs (such as the heart) to help compensate the higher metabolic needs. So, whilst the Titan Blowhog is a more powerful version of the Fiery Blowhog, the unregulated tissue growth can lead to joint strain, organ stress, and mobility difficulties. The Titan Blowhog will likely struggle to function normally due to its larger body because its behavioural adaptations have evolved to work when it is at a smaller size. Additionally, the Blowhog may face difficulties with its cardiovascular system. These health difficulties are likely to make the Blowhog have a shorter lifespan, and it will struggle to reproduce.
Burrowing Snagret
Intro
Burrowing Snagrets (Shiropedes anacondii) are creatures resembling a mix between a snake and a bird. They are ambush predators and often spend their adult lives underground. They have strong, blue-coloured scales that help negate any damage dealt to them, and they have a sharp beak capable of rapid strikes. These traits make it an apex predator, and its burrowing ability makes it able to survive for decades. However, its head is covered in weak, white-coloured feathers that are susceptible to damage. The Snagret's neck is serpentine-like and gives extreme flexibility, allowing for a large range. There have been multiple species of Snagret spotted in the wild, those being the Pileated Snagret and the Burrowing Snarrow. The Pileated Snagret greatly resembles the Burrowing Snagret, but it instead has green-coloured scales and an orange-feathered head. Additionally, the Pileated Snagret has the ability to jump and move above ground, making it a deadlier version of the Burrowing Snagret. The Burrowing Snarrow resembles the Burrowing Snagret even further, but photographic evidence does not exist. The only way to tell the difference between the Snagret and the Snarrow is by the presence or absence of tail and wing markings. The Burrowing Snagret is known to have only 1 stage of development: the Downy Snagret (Shiropedes anacondii (fledgling)), often residing above ground in packs or inside of nectar eggs.
Taxonomy
Burrowing Snagrets are ambush creatures. They will occupy a space once they have reached full maturity and will never move. This behaviour is because of the lack of mobility. They have a talon-like appendage that could be used for movement, as seen with the Pileated Snagret, but they instead prefer to use it to dig. They feed on any insects that enter its territory but will also eat larger creatures if needed.
| Taxonomy | Relation |
|---|---|
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | [Unknown] |
| Order | [Unknown] |
| Family | Snavian |
| Genus | Shiropedes |
| Species | S. anacondii |
Description
The Burrowing Snagret appears to be the mixture between a snake and a bird. The Snagret has an avian-like head, covered in white feathers, and is equipped with a long, sharp beak built for rapid and precise strikes. Its blue eyes face forward, giving it excellent depth perception that helps with hunting. Its body, on the other hand, is more snake-like. It is serpentine, covered in blue-coloured scales that make it invulnerable to any form of damage. Its snake-like body allows for it to burrow underground with incredible ease. The Snagret's neck is unnaturally long - a prominent feature - capable of fast turns which the Snagret has full control over. It is also flexible, allowing for it to ambush prey with ease. Despite its appearance, the Snagret is more avian in nature, due to its respiratory system having more in common with birds than reptiles. Additionally, the Snagret has a talon-like foot, which helps it stay underground and dig quickly.
Ecology
The Burrowing Snagret is an incredibly versatile creature, capable of surviving in a multitude of environments, such as warm climates to underground caverns. The Snagret is capable of living in nearly every environment, making it one of the planet's most geographically represented creatures. The Snagret relies on its ability to burrow underground to survive. It digs into soft soil and dirt, as well as snow and cracks in the ground. However, it does require the ground to be semi-soft or to have natural cracks. If these are not present, the Snagret is unlikely to survive.
Diet
The Burrowing Snagret, like most creatures on the planet, prefers to diet on smaller creatures such as insects or Pikmin. Its sharp beak and precise control over it allow for fast strikes on any moving insects or Pikmin that have entered its territory. Due to its ambush strategy and its lack of mobility above ground, the Snagret never chases prey. It relies on staying hidden underground and then swiftly striking any unsuspecting victims. Its long neck allows it to attack at a distance multiple times in quick succession, which helps it consume enough food to survive. While it prefers small critters, the Burrowing Snagret is not a picky eater and is known to eat larger creatures, such as Sheargrubs and Dweevils. However, larger Snagrets (which are extremely rare to see) have been known to eat Dwarf Bulborbs and Breadbugs. This is uncommon, however, as the Snagret's physiology isn't suited for larger creatures.
Interaction with other creatures
The Burrowing Snagret is a solitary creature, as they are often found alone. Its aggressive hunting techniques and its territorial nature mean it prefers a lonely lifestyle. However, they are sometimes spotted with another Snagret, which is likely a mate. Snagrets don't have many social interactions, except with their young. Downy Snagrets, known for their smaller size and inability to burrow, are often seen in a Snagret's territory. These situations are key for a Downy Snagret's survival as they are taught how to hunt and burrow as well as being protected from predators. The presence of Downy Snagrets suggests a level of care and nurture, often seen with birds and not snakes, making it lean more into its avian lineage.
Infections/Diseases
Despite the Snagret's large geographic representation, they don't show any signs of infections or diseases. This could stem from their solitary lifestyle and the fact that they are often underground. This would minimise their exposure to pathogens in the air. However, due to their wide diversity, Snagrets in certain environments may be exposed to environmental issues that affect other creatures in the area. This is particularly true for swampy and humid environments, known for being inhabited by Toxstools. These are essentially walking fungal infections, which could pose a risk to the Snagret. The Toxstool will infect living organisms with a fungal growth, and they will then hunt for food before turning into another Toxstool. Due to the Snagret's large body and how they often hide underground, they may be safe from infection. Additionally, it is unknown whether the Toxstool can infect large creatures, as only smaller creatures have been sited.
Yellow Wollyhop
Intro
Yellow Wollyhops, or Yellow Wollywogs in certain areas (Amphicaris frondiferorum, previously referred to as Amphicaris frodendum), are amphibian creatures resembling the likes of frogs. These frog-like creatures spend a majority of their lives in watery areas. They are known for their powerful jumping abilities and their rubbery skin. Their rubbery skin is yellow in colour, likely making it a form of camouflage or warning depending on its environment. Despite their blump bodies, they are highly agile, using their strong legs to leap a great height—both to evade threats and to attack prey. There are three known stages of a Yellow Wollyhop's development: the Wolpole, the Young Yellow Wollyhop, and then the Yellow Wollyhop. Wolpoles bear a striking resemblance to real-world tadpoles (some Wolpoles were spotted in the wild with small arm-like appendages; such sightings have not been seen again). They have greenish skin, no legs, and a tail. The Young Yellow Wollyhop looks like a mixture between the Wolpole and the Yellow Wollyhop—they have two legs, a smaller tail, and have started to turn yellow. However, if an adult Yellow Wollyhop's territory features no threats or issues, they will continue to grow in size. These gigantic Yellow Wollyhops are referred to as Masterhop.
There are multiple species of Wollyhop in the world, such as the albino-looking Wollyhop, the frost-covered Chillyhop, and the flame-ridden Fiery Young Yellow Wollyhop. The Wollyhop resembles the Wollyhop slightly, though it lacks the yellow colouration and the height of the Yellow Wollyhop. The Wollyhop might not be able to jump high, but they can jump a lot further. The Chillyhop resembles the Yellow Wollyhop extremely, although these also lack the yellow colouration. They instead are coated in an icy-blue colour and are surrounded by a small frosty fog. The Fiery Young Yellow hop bears a striking resemblance to Young Yellow Wollyhops, although these Fiery variants are orange in colouration and expel a fiery substance, akin to Fiery Bulblaxs.
Taxonomy
Yellow Wollyhops are territorial creatures. They will generally stay in a small location, often in groups, and never move. The reasoning for this behaviour is unknown at the time, but theories generally state that, since their territories are near water bodies, they don't move due to them protecting their young.
| Taxonomy | Relation |
|---|---|
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | [Unknown] |
| Order | [Unknown] |
| Family | Amphituber |
| Genus | Amphicaris |
| Species | A. frondiferorum |
Description
The Yellow Wollyhop is a large, frog-like creature that has a rounded, muscular body that is equipped with 4 powerful limbs adapted for leaping into the air. Unlike most other frogs and toads, the Yellow Wollyhop lacks webbed feet. They instead have individually split toes, 3 on each foot, that are padded. The lack of webbed feet is due to them spending more time on land rather than in water. These padded toes help the Yellow Wollyhop with mobility in their watery habitats, such as beaches or swamps, as they are often uneven or muddy. Their front two limbs are comparatively smaller in size, and they are rarely used for walking. A Yellow Wollyhop will only move about in small hops, which is why their back two limbs are larger in size.
The Yellow Wollyhop's body is relatively simple, as it has a wide, flattened back with a rounded belly. It lacks any form of neck; its eyes, beady and large, are positioned on the upper part of its head. A Yellow Wollyhop's body, its most striking feature, is vibrant yellow, with a small green patch at the top of its head and three green-coloured dots on each side of its upper half. Their bodies are thick and rubbery, providing both protection and moisture retention. Their colouration serves as both a warning to potential predators (similar to the Bulborb's red body) and as camouflage, helping it blend into their marshy territories where there's lots of algae and sunlight.
Whilst the Yellow Wollyhop doesn't appear to have a mouth, it does consume prey. It consumes its prey by absorbing the bodily fluids from the creatures it crushes. The underbelly of a Yellow Wollyhop is lined with a specialised, pore-ridden, skin that allows it to extract these fluids. Certain frogs are known to do this as well.
Ecology
Yellow Wollyhops are primarily located in warmer environments, favouring areas near large bodies of water such as lakes, rivers, or swamps. Their semi-aquatic adaptations allow them to thrive in these types of areas, as it prevents their rubbery skin from drying out. Despite its frog-like nature, they are never seen fully submerged in water, except from the Wolpole stage of life. However, despite their reliance on water, Yellow Wollyhops avoid colder climates, and they are never found in these regions. Their physiology appears to be suited for warmer conditions with plenty of rainfall. They are commonly seen in areas overgrown with vegetation. Additionally, they are often spotted in caves, though less frequently. Their albino cousins, the Wollyhop, are spotted more often in these areas. The caves inhabited tend to have high humidity levels and good access to water, suggesting that moisture is a key aspect of their survival.
Diet
Like most predators on PNF-404, Yellow Wollyhops are carnivores that have a keen interest in Pikmin. They feed on smaller creatures, such as insects, small Sheargrubs and Shearfleas, by crushing them and eating the bodily fluids. Larger Yellow Wollyhops, or Masterhops, have been seen consuming small Bulborbs. The largest spotted Masterhop to date (06/03/2025) has been seen consuming an entire Sandbelching Meerslug. It has a unique method of eating, as Yellow Wollyhops lack a mouth, so they absorb the bodily fluids through their porous skin, extracting the necessary nutrients. This adaptation is highly efficient, as it means they have no need for a large digestive tract. Specifically for Yellow Wollyhops in caves, they are often seen scavenging around for leftover prey and, in rare circumstances, eating plant life (although they haven't been seen eating Glowstems...).
Interaction with other creatures
From large studies, Yellow Wollyhops are semi-social creatures. They are often found living in small groups, yet they hunt on their own. These small groups usually comprise two to three individuals, though larger clusters have been rarely seen. However, they do hunt alone, likely so there's no intraspecific competition for food.
One defining characteristic of Yellow Wollyhops is their behaviour of looking after their young. Adults remain near large water bodies where their offspring (Wolpoles) develop. During a Wolpole's growth cycle, the Yellow Wollyhop will provide protection by keeping predators at bay; whilst they are territorial, they are even more so during their protective state. Unusually, they don't feed their young, instead making them hunt for their own food (food that is usually microorganisms or detritus). Once a Wolpole reaches the Young Yellow Wollyhop stage, the Yellow Wollyhop will stop protecting them.
Although Yellow Wollyhops share their environment with other species (such as Blowhogs), they appear to be largely indifferent. Smaller organisms (such as Sheargrubs) that enter nearby will be at risk, but similarly sized creatures will be fine. A small study on Sheargrubs has shown that they avoid Wollyhop-inhabited areas due to the risk of being eaten.
Infections/Diseases
Yellow Wollyhops are one of the few creatures on PNF-404 that have not been observed suffering from infections or diseases, suggesting an advanced immune system. Their thick, rubbery skin has been examined in detail, and it has been found that it created a protective barrier against parasites and bacteria, meaning they are unlikely to be infected by a Toxstool's pathogen, for example.
One of the most remarkable aspects of a Yellow Wollyhop is its ability to continuously grow throughout its life, only when they are in ideal conditions—no predators, no food issues, etc. Key research suggests that this is due to the species having unusually active telomerase enzymes, preventing cellular ageing. Unlike most creatures whose cells gradually deteriorate over time due to telomerase shortening, the Yellow Wollyhop's cells are forever young. This allows for near-infinite growth in the right circumstances. Due to this, there have been individuals seen over the age of 50, and their size is, on average, 3x the size of a regular Yellow Wollyhop. Yellow Wollyhops that experience this phenomenon are referred to as Masterhops. The largest seen Masterhop was bigger than a Sandbelching Meerslug (one of the largest known creatures on the planet).
While this unusual growth provides its advantages, there are disadvantages too. Their larger size means they won't be predated on, but they will require more sustenance. If there are no large prey in the area, they will likely starve. Similar situations can be seen with real-world crocodiles.