#loricifera

she's all about glass. she lives in a glass house (which gets pelted by stones every night), eats glass food, reads glass books and drinks molten glass!

she also does glass tap dancing every glass tuesday night. on a glass stage of course

how glassy

glassiness rating: how elephant

(Sources - 1, 2, 3, 4)

Loricifera is a very small phylum of microscopic to near microscopic marine animals with 43 described species (but more than 100 remain undescribed) that live in the small spaces between the marine gravel they attach themselves to. They range in size from 100 micrometre to 1 mm long.

Loriciferans are characterised by a protective outer case called a lorica. They have a mouth, digestive system, and a brain, but no circulatory or endocrine system. They feed on suspended organic particles, microalgae, and bacteria, by piercing them with their oral stylets and then sucking out the contents. Most species have males and females, but some are hermaphroditic. Little is known about their mating behavior, but they have a complex life cycle. They are found worldwide, in a variety of different types of sediments, and at all depths. In fact, three species have been found living in oxygen-free sediments at the bottom of the Mediterranean Sea, more than 3,000 meters down. These are the first animals known to spend their entire lives without light or oxygen. Fossil loriciferans have been dated to the Late Cambrian.

Propaganda under the cut:

Loricifera: Microscopic animals with a hard shell and a head surrounded by elongated spines. All animals in this phylum are "meiofauna", meaning they live in the spaces between grains of sediment on the seafloor. They are distinguished by the "lorica", the hard casing surrounding most of their bodies, which can sometimes take on a corset-like appearance. Loriciferans were only recently discovered - they can attach themselves extremely well to grains of sand, which made them very difficult to find. Interestingly, some of these animals have a unique high tolerance for zero-oxygen conditions, which they owe to specialized organelles in their cells called "hydrogenosomes" which have replaced mitochondria.

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

Cambrian Explosion #36: Phylum Loricifera

Even more obscure and poorly-understood than the mud dragons, loriciferans weren't even discovered until the 1970s. Over 40 living species of these tiny meiofaunal animals are currently known, but much like the kinorhynchs there are probably many more still to be described.

Less than 1mm long (0.04"), their most distinctive feature is the "lorica", a stiff corset-like casing surrounding their body. They're also the first multicellular organisms discovered able to live completely without oxygen in a deep basin in the Mediterranean Sea.

Traditionally loriciferans have been considered to be part of the scalidophorans, closely related to priapulids and kinorhynchs, but genetic studies have suggested they may actually be much closer related to nematoids and early panarthropods instead.

(The nematoids – nematode worms and horsehair worms – don't have a definite fossil record until the Devonian, and won't be making an appearance in this series. There's one possible larval form from Australia, but with all the disagreements about the mess of early ecdysozoan relationships it's unclear where exactly it actually fits in.)

Loriciferans have a very sparse fossil record – like the kinorhynchs and other meiofauna they're basically "paleontologically invisible" – but there are a few known Cambrian fossils of the group. The minute Eolorica from the late Cambrian of Canada (~497-485 million years ago) is incredibly similar in size and appearance to modern loriciferans, showing that by that time these animals had already taken up the same sort of ecological role as they have today.

But further back in the Cambrian there was something that may actually represent a very early or "stem" loriciferan.

Sirilorica carlsbergi is known from the Sirius Passet fossil deposits in Greenland (~518 million years ago). It was a worm-like animal with a tube of loricate plates around its body and spines around its head, and it was much bigger than modern species, up to about 8cm long (~3").

It suggests that modern-style loriciferans are actually highly miniaturized and neotenous, evolving to retain a tiny larva-like body plan and exploit a fully meiofaunal lifestyle, and lost their original larger worm-like adult forms in the process.

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Here’s my next installation of my Pangea Ultima Project.  I’m particularly proud of this piece as I managed to design an entire family of future organisms based on a group that’s I don’t think has ever been focused on before, that group being Loriciferans.  As stated in previous post about this project, the global ocean surrounding Pangea Ultima has become mostly anaerobic due to the lack of stable ocean currents.  This resulted in most oceanic life dying off.  However, there are currently three species of Loriciferans that have been discovered that live their whole lives without oxygen.  So as oxygen levels dropped, the Loriciferans started to grow and diversify.  250 million years into the future, the global ocean has become dominated by two groups of Loriciferans: ones who evolved from the larva (the most numerous) and ones who evolved the adults.  Here are the species from top-to-bottom and left-to-right:

Algae Eater: This species lives amongst the stromatolite reefs grazing on their leafy structures, only retreating to deeper water when super storms make landfall.  The Algae Eaters also help distribute spores, ensuring genetic diversity among the reefs.

Squid Mimic:  One of the few free swimming “adult” Loriciferans, the Squid Mimics adopted a body plan similar to their namesakes and form large schools that feed on anything small enough to fit into their mouthes.

Zooplankton Loriciferans:  Similar in size to their distant ancestors, Zooplankton Loriciferans feed on diatoms and oceanic, photosynthetic bacteria.  Just as krill did in the past, Zooplankton Loriciferns have become the most abundant species on the planet, forming the basis of the global ocean’s food chain.

Bottom Shuffler:  Resembling a mix of flatfish and crustaceans, Bottom Shufflers are “adult” Loriciferan scavengers that sweep anything they come across into their gaping mouthes.

Bottom Crawlers:  Like the Bottom Shufflers, Bottom Crawlers are “adult” Loriciferan scavengers.  Unlike other Loriciferans, however, their mouths face downward and scuttle across the ocean floor like crabs.  This position allows them to retreat into their shells when predators approach.  Whenever a carcass sinks to the bottom, Bottom Crawlers are often the first to arrive on the scene.  They are followed by Bottom Shufflers who feed on the scraps that the Crawlers leave behind.

Shore Stalker: These meter long predators inhabit shallow water along the coasts.  They body color allows them to blend in with the water while the red markings allows them to sneak up on schools of Algae eaters as well as attract flying animals such as Sea Wasps to their awaiting jaws.

Sea Scurrier: Among the most unspecialized of the Loriciferans, Sea Scurriers filter feed as well as hunt small prey.  Coupled with powerful hind legs for escaping predators, Sea Scurriers have been able to inhabit almost any environment in the global ocean.

Lock Jaw: The largest of the Loriciferans at around 2.8m (9ft), Lock Jaws are apex predators that hide in the depths, waiting patiently for unsuspecting prey.  When a Target has come into range, they ambush from bellow, crushing through the hardest exoskeletons with their powerful jaws.

Pod Shell: Pod Shells are normally found around hydrothermal vents, feeding on bacteria gardens that grow amongst them.  Whenever approached by a potential predator, they retreat into their shells with their middle ring of fins forming a conical structure at the entrance.

Feather Mouths: An Equivalent of baleen whales (though not nearly as large), Feather Mouths travel in pods sweeping in clouds of plankton into their large mouths.  They are the preferred prey of Lock Jaws.

Snake Neck:  The most unique Loriciferan species, Sanke Necks are opportunistic hunters whose body plans resemble long extinct plesiosaurs.  Like Shore Stalkers, Snake Necks use their head marking to either approach prey or drew it to them.  Their long necks and narrow heads also allow them to sneak into narrow spaces where other wouldn’t normal reach.

Onychophora: Velvet Worms. This is the only phylum containing exclusively terrestrial members, although their ancestors can be traced back to the Cambrian shallow oceans. Onychophorans are ambush predators, moving with slow smooth steps to creep up on their prey. They have unique mucus glands on either side of their face which can spray jets of sticky slime, which effectively immobilizes their prey. Onychophorans have relatively complex brains, and some even live in social "packs" that live and hunt together. Many species in this phylum are ecologically vulnerable, threatened, or endangered.

C. elegans. This nematode species is commonly used as a model organism, being the first multi-cellular organism to have its genome sequenced and neural connections mapped

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