SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9234cccdf71d8d3a9dda0654035e042ff45dac80695f019429e8bf93c5308640' 
  AND token = 'M+C16mHAxlPYsgbuG9476CFaFscT1zlzEzE3VHHj2X4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables