SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3bd42da63bb60769639e2aa16ef7176abfffd8ef68ee8f794d4d25a2ffecfb83' 
  AND token = 'TrbbYZvUxMZkfFLDTg8YMfYU68aDzmA8G5j7ZZEwvno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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