Hmmmph. I'm a bit miffed. The New York Times is finding the news so slow (ha!) that they can write fluff about Friday cat blogging by the usual suspects, but week after week I tell you all about much more interesting beasties, and do I get any mention? Noooooo. Just because I'm more interested in things with suckers or spines instead of fur, or antennae instead of eyes, or tentacles instead of paws, or that are dead instead of playing with balls of yarn, I get no respect. Dang pandering felines—you know they're just sucking up to you with that purring crap and that soft, furry pelt.

Now here's an animal with integrity, one with a little self-respect that demands you to love it for what it is. It's called Leanchoilia superlata, a very pretty name. It was a blind arthropod bearing a pair of spectacular "great appendages" on its front end, each with a trio of whiplike lashes. This general layout seems to have been a successful morphological strategy in the Cambrian: Opabinia, Anomalocaris, Yohoia, and Fortiforceps all seem to have adopted the habit of carrying around great whacking claws or knives or clubs as their frontmost appendages. Leanchoilia probably used theirs as sensors, flicking them over the surface in search of prey, and as graspers, clutching their victims to their mouthparts for consumption.

The other distinctive feature is their gut—several papers have been written about the spectacular Leanchoilia gut. It fossilizes unusually well, preserving a fair amount of fine structure, revealing that it is thickly surrounded with glandular tissue. This also suggests a few things about taphonomy.

Phosphatization of soft tissues in the Burgess Shale is restricted to particular taxa, indeed to particular organs of particular taxa. In Leanchoilia, for example, it is limited specifically to the midgut and possible excretory organs on the third podomere of its great appendages. Such specificity suggests that the source of the phosphorus ions was internal, i.e., derived from the organs themselves. Likewise, the absence of any Santana-type preservation of muscle argues convincingly against a significant external source of phosphorus. In this light, it is interesting to note the abundance of unordered “mineral” spherites characteristic of many arthropod midgut glands, sometimes to the extent that they constitute a substantial fraction of the solid feces. Rich in both phosphorous and calcium, these offer a ready source of permineralizing ions, as well as abundant, localized nucleation sites.

Isn't a bizarre chitin-covered nektobenthic predator with guts and half-billion-year-old fossilized poop much more interesting than yet another boring cat?

By the way, at least The Modulator's Friday Ark pays attention to a little zoological diversity. And at least one other person recognizes the intrinsic interest of invertebrates.

Butterfield NJ (2002) Leanchoilia guts and the interpretation of three-dimensional structures in Burgess Shale-type fossils. Paleobiology 28(1):155–171.