Dinky interstitial phyla

The first week or so of this taxonomy course was a whizz through the tree of life, to get us all familiar with most types of organisms at the most basic level. One lecture managed to cover all fourteen phyla in the group of animals called Lophotrochozoa. For perspective, a phylum is a very deep level of organisation for animals that divides them by their basic body plan. Phyla vary hugely in how many species they contain, but we belong to the phylum Chordata, which contains every single vertebrate plus a few of our very close invertebrate relatives, like tunicates (sea squirts). The lecturer did a fine job of not running out of breath.

I'd met all of Lophotrochozoa briefly before, on my biology course, and two phyla stood out both times. I'd doodled them to try and remember what they looked like, and they are just adorable. Both contain exceedingly tiny animals that live between sand grains - that makes them 'interstitial', in the same way that animals that live on the sea floor are benthic. Meet Kinorhyncha and Gastrotricha respectively, in fabulous microscopy:

I know, they're like hairy sausage puppies with bowl-cuts and glitter, right? And in less fabulous Paint.NET (not to scale):

Or even in the Vesryn region:

References
Kinorhynch photo:
http://palaeos.com/metazoa/ecdysozoa/scalidophora/kinorhyncha.html
Gastrotrich photo:
https://tl.wikipedia.org/wiki/Talaksan:Gastrotrich.jpg
Screenshot adapted from Pokemon Zeta, a real gem of a game: https://www.reddit.com/r/pokemonzetaomicron/