#mollusc

and the slugs...................

Today’s daily critter is a species of terrestrial snail called the Grand Canyon Talussnail (Sonorella coloradoensis) [1]. Unsurprisingly, they are found in the Grand Canyon in the USA, more specifically Arizona [2] and were actually the first Grand Canyon mollusk described [3].

They were first found there in 1889, with the original author describing their occurrence at a height of 1066 m opposite the Kaibab Plateau [4], however later authors point out that this isn’t a very exact description, as the Kaibab Plateau is quite large and when they asked, found the locality described closer to the Walhalla Plateau [2]. Since then they have actually been found at many more locations along the Colorado River segment of the Grand Canyon, ranging across life zones [3]. Their colonies are isolated and mostly small, staying near eruptive or metamorphic rocks [2].

They have two subspecies [5], whose main difference is in size. The shells of S. c. coloradoensis are around 1.5 cm in diameter, with a max of 1.8 cm, their penis is around 5 mm, and their vagina around 3 mm. Meanwhile S. c. mohaveana has similar genitalia size (differing slightly in the structure), but has shells of up to 2.05 cm [6]. The shell pictured above is actually of the holotype (so individual upon whom the species is based) of S. c. mohaveana, collected in 1967 [7].

chordata (vertebrates and close relatives)

i don't need to convince you to vote for chordata. for chordata ? for the fucking vertebrates ? i mean, sure, there's the tunicates who are beautiful and diverse and bizarre in their own right, but you care about the vertebrates, don't you ? you're voting for chordata because it has the all of the fish of the seas, the toughness of the reptiles, the majesty of birds, the the creativity of the mammals, and crucially, you. why, wouldn't everyone vote for themselves on a ballot if they could ? the chordates contain the only species that could even fathom making this poll, that has the curiosity to have learned this much about the natural world, the innovation to invent the computer and everything leading up to it, and the culture to be able to write like this. chordates have an endoskeleton -- they're even named after it -- and the combined squishiness of the outside and rigidity of the inside allows them incredible flexibility while also being able to support their own weight, which enables them to do things that other phyla only dream of. the lungs of tetrapods are the single best way of extracting oxygen that animals have yet discovered, and this has allowed them to become the largest animals who have ever lived, both on land, in the sea, and in the air. while flight has only been achieved once in invertebrates, vertebrates have done it thrice. the primates, living in niches that demand creativity, have developed the largest and most sophisticated brains among any animal. chordates are the most advanced phylum there is, and that's why you should vote for them.

vs

mollusca (snails, squid, clams, etc)

allow me to show my hand a bit here. my favorite phylum, cnidaria, has already been eliminated, but admittedly they mostly have blorbo appeal to me. in terms of things i think are beautiful about animals, mollusca is the best phylum. their body plan couldn't be simpler: a shell to protect them, some horny mouthparts to eat with, some muscles to move them around, and some internal organs, and molluscs have developed every variation on this imaginable. the snails have placed the shell on top of them, adapted the mouthparts into a sandpaper-like tongue, and adapted the muscles into a slimy foot that they crawl along the ground with. some snails have placed their shells inside their body and made them very small, and become slugs. the nudibranchs (sea slugs) alone have an incredible diversity among them, having developed beautiful coloration, innovative ways of swimming, and one genus, Glaucus, has even devised a way to crawl upside-down along the surface of the water. the cephalopods, on the other hand, have adapted their muscles into an array of muscular, dextrous arms, and while the ammonites and nautiluses fill their shells with air to maintain buoyancy, the squids and cuttlefish have reduced them into small internal bones that help them maintain rigidity, and octupuses have lost them altogether. all cephalopods have adapted those mouthparts into two cutting blades resembling a bird's beak, granting them access to extremely tough and hard-to-reach foods. when you combine that capacity for opportunism with arms that can manipulate things with utmost strength and precision, they have achieved creativity and intelligence second only to the smartest of vertebrates. and yet another group of molluscs has gone all the way in the opposite direction: the bivalves have grown their shell large enough to encase their entire body, and their muscles have adapted to clamp that shell shut firmly as well as circle water through their shells to feed on plankton. the molluscs have developed an incredible variety of bodies, from some of the most beautiful to some of the most intelligent to some which don't even look like animals. molluscs are the most diverse phylum there is, and that's why you should vote for them.

Submitted for classification by @five-red-feathers

The snail. We Look About Us. 1932. Illustrated by Hugh Spencer.