== mess in mass == 
 the logic of saying small colonies do not represent an invasion seems a little weak. in massechusetts my housemate had a black disk the size of doily that never healed properly. i finally caught one of these things that have been crawling on me at night. i lived in kansas for two years and became way too familiar with these critters. also the criticism of light avoidence is correct. it is not a hard rule. in kansas i saw them all the time. i had them verified by a bug person at ksu.   grumpy