#kinorhyncha

[bestanimal]

Round 1 - Phylum Kinorhyncha

(Sources - 1, 2, 3)

Kinorhyncha is another phylum of small marine animals that live in mud or sand at all depths. They are commonly called “Mud Dragons”.

Kinorhynchs are segmented, with juveniles having 8 or 9 segments, depending on species, and growing 2 or 3 more with age. Instead of cilia they have hollow, moveable spines along their body and around their head, which they use for locomotion. Like many arthropods, they molt an outer layer of tough cuticle as they grow to adulthood. The head is retractable, and is protected by a set of neck plates called placids when retracted. Some species have simple eyes, but all species use tiny bristles to feel the world around them. They eat diatoms or other organic material found in the mud. They have two sexes which look alike, and larvae are free-living. Most species are around 1 mm or less, though extinct Cambrian species could reach up to 4 cm (1.6 in) long.

How do you feel about this phylum?

One or more of my favorite animals is in this phylum

I love one or more of these animals

I like one or more of these animals

I am neutral about all of these animals

I dislike all of these animals

I hate all of these animals

Voting ended onSep 19, 2024

Propaganda under the cut:

Mud Dragons

Kinorhynchs have been found from 8-8,000 meters deep

By feeding on detritus, bacteria, algae, or diatoms, kinorhynchs play a vital part in the food web, converting otherwise inaccessible nutrients in the mud into energy.

Female kinorhynchs will wrap their eggs in mud and other organic material after laying them.

Mud Dragons

[animalshowdown]

Phylum Round 1

🦠 ROTIFERA vs. KINORHYNCHA 🦠

Rotifera

Kinorhyncha

Voting ended onJan 28, 2024

Rotifera: Wheel Animals. Mostly freshwater with some saltwater species, and can live in the water column, within the sediment, or attached to hard surfaces. Some Rotifers even live within the thin layer of moisture covering mosses. Their most distinctive feature is their corona and tentacles, which, when feeding, look like a rotating wheel. Their bodies are entirely soft except for the small jaw-like structures in their throats that help them chew their food. As detritivores, they are important contributors to the nitrogen cycle and breaking down dead organic matter.

Kinorhyncha: Mud Dragons. Kinorhynchs are meiofauna, meaning they live in the spaces between grains of sand. They are segmented and have sets of spines along the body. These spines are used to move through the sediment, gripping individual sand grains as the body moves forward. A crown of spines around the head frames the mouth, which is full of sharp toothlike spines. Although little is known about their life cycle, research has shown that mother Kinorhynchs wrap each egg in a protective layer of mud and dead organic matter until the young hatch.

[taxonomytournament]

Taxonomy Tournament: Ecdytes

Kinorhyncha. This phylum is made up of tiny benthic organisms, known as mud dragons

Priapulida. This phylum is made up of unsegmented marine worms known as penis worms.

Which clade of animals is better?

Kinorhyncha

Priapulida

Show results

Voting ended onFeb 14, 2024

[alphynix]

Cambrian Explosion #35: Phylum Kinorhyncha

After the slightly unfortunately-shaped priapulids, let's move on to something much safer-for-work: dragons!

More accurately, kinorhynchs, tiny spiky scalidophoran worms with the delightful common name of "mud dragons". These animals weren't even discovered until the mid-1800s and are so small – less than 1mm (0.04") in size – that they're considered to be "meiofauna", wriggling around between grains of sediment using the spines on their heads to pull themselves along.

They're a widespread and abundant phylum with around 300 known living species, but they're also a very understudied group. Only a handful of scientists specialize in them worldwide and most research on them has been done in just the last 60 years, and so there are thought to be many many more species still out there to be discovered.

While these little dragons must have diverged from other scalidophorans at least as far back as the early Cambrian, they have basically no fossil record at all. A ghost lineage of over half a billion years.

Currently the only known exceptions to this are a few incredibly rare fossils from the early Cambrian of China. The recently-discovered Qingjiang fossil deposits (~518 million years ago) include some currently-undescribed specimens up to 4cm long (~1.5"), and if these do turn out to be kinorhynchs they indicate that modern forms may be highly miniaturized versions of much larger ancestors.

And some slightly older fossils from Sichuan, dating to about 535 million years ago, give us another possible ancient mud dragon: Eokinorhynchus rarus.

This species was much smaller than the Qingjiang forms but still twice as big as modern kinorhynchs at around 2mm long (0.8"). It had more body segments than living mud dragons, and a different pattern of spiny armor, suggesting it was probably part of an early stem-kinorhynch lineage rather than a true member of the group.

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Nix Illustration | Tumblr | Twitter | Patreon

[taxonomytournament]

Taxonomy Tournament: Ecdytes

Loricifera. This phylum is made up of microscopic animals that attach themselves to gravel. It is one of the most recently discovered groups, first described in the 1980s

Kinorhyncha. This phylum is made up of tiny benthic organisms, known as mud dragons

Which clade of animals is better?

Loricifera

Kinorhyncha

Show results

Voting ended onMar 14, 2024

[parakaryote]

Part 2 of the InverteFest drawings!

The Kinorhyncha one is referencing the phylum’s nickname of “mud dragons”.

[Image description: Six digital drawings of animals from small phyla.

Picture 1: A Saccoglossus acorn worm curled into a loose spiral.

Picture 2: An Echinoderes kinorhynch with silhouettes of dragon wings drawn on either side of it.

Picture 3: A loriciferan with the caption “Loricifera: Living it up in the anoxic zone!”

Picture 4: A horsehair worm curled into a horseshoe shape, with the caption “Not the actual horseshoe worm, that’s still coming up!”

Picture 5: A blue velvet worm with golden/orange spots crawling on a mossy surface.

Picture 6: The actinotroch larva of a phoronid / horseshoe worm.

End ID.]

[typhlonectes]

The Mud Dragons of Calvert Island, BC

Shedding light on these mysterious marine creatures.

by Josh Silberg

Spiky headed dragons roam the ocean floor from the poles to the tropics. But these are not winged beasts from the pages of science fiction. These strange creatures are Kinorynchs, aka “mud dragons“, and they are very real.

Roughly the size of a grain of salt, mud dragons are often overlooked, but a team from the Hakai Institute and the University of British Columbia (UBC) hopes to give them the spotlight they deserve.

“Canada has very few reports on these animals. The first step is to know what is there,” says Dr. Maria Herranz, a Hakai post-doctoral scholar and resident mud dragon expert at UBC...

(read more and see video: Hakai)

images by Marria Harranz

[pagurus]

Kinorhyncha

Taxonomy: Animalia, Kinorhyncha

Description: Commonly known as mud dragons, kinorhynchians are vermiform organisms with 11 trunk segments defining their bristled bodies. Their mobile mouthparts are surrounded by seven rings of scalids. The body is covered in a cuticle, which is shed throughout its life cycle. The body is covered in sensory hairs and adheisive tubes.Internally, kirnorhynchians have dual nerve chords and a brain surrounding the pharynx (akin to what is found in cephalopods). Species in this phyla reach up to 1mm in length.

Lifestyle: kinorhynchians live in sediment, moving via contracting and relaxing their scalids, which pull the organisms through the sediment. They feed on diatoms and/or organic material, depending on the species. How this phyla reproduces is unknown, though they do posess two separate sexes.

Photos from scrubmuncher (Dr Ross Piper), ZMUC, and Reefkeeping.com.