A photo would be helpful.  The most common Scorpion found in Texas is the Mexican brown. They are usually about 2 to 3 inches in length.  They are poisionous and hurt worse then a wasp sting.  I doubt they could kill a dog though but it may be possible depedending on the size of the dog and if its allergic to the sting.   Generally speaking the smaller the scorpion the worse the sting is.

Weird about the dog dying...  We have them everywhere west of Fort Worth, my 3 year old ate one, and somehow managed to not get stung, I stepped on one last year in my Kitchen and I thought I stepped on a hot coal!! Had to favor one side of my foot for about a week, so I guess it is poisonous, but not life threatening.

Just to clarify, he's 3 now, 9 months when the scorpion eating took place!!! 

I've been hit several times and the pain is instantaneous and searing, just like a red hot needle. The strike site stays tender for a few days but, surprisingly, doesn't swell. Our Lab stepped on one in the bedroom and yelped but crushed it. She limped for a day but suffered no other effects.