Lots of photos for this one...
The main skin tone is from Army Painter Desert Yellow, which is a nice, high-pigment paint available in a spray can. I used several washes, some wet brushing and some old fashioned highlights to get the skin and carapace just right.
All of the larger beasts in this army have exotic carapace patterning; I had really wanted to do some "stripes" (inspired by "Spike" from Gremlins 2) and this model gave me a good chance to go with that.
This photo shows the carapace well...
This beast is based on a Secret Weapon "hive" base - it has excellent detail and really fun to paint. The Exocrine needs a flat surface for all four feet, so I built up one side of the base with greenstuff. This was surprisingly easy to do, and the model therefore sits nicely. I pinned the feet and arms into the base, so hopefully he'll be nice and stable for gaming.
On the plasma cannon, I used a turquoise wash and then coated the tip of the gun with Vallejo water effects. This is a nice finish, I think, because it remarks the cannon as being something a bit special. It's important not to overdo this though, as water effects are easier to apply in successive thin coats than a single "gloopy" coat.
Lots more to do on the Tyranids - hoping to get underway on a Hive Crone next week, plus some of my own miniatures for my Savlar Chem Dog army, and maybe a (late) review of the Astra Militarum codex...