SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b7de66df7775de469bd00f3957a9b7dc683fac55dc537e0b3e1fb9fe2d88adb1' 
  AND token = 'Y8qdFpDaEK0R9hyEaQpot3dA+CxMe6FebhXSR4+l2bg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

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